阅读说明：本技术 抑制输出电压或输出电流过冲的方法、充电设备和介质 (Method for suppressing overshoot of output voltage or output current, charging device, and medium ) 是由 范锋 张凯旋 吴奕赛 李晨光 付加友 张海东 朱建国 于 2021-08-25 设计创作，主要内容包括：本申请公开了一种抑制输出电压或输出电流过冲的方法、充电设备和介质。该抑制输出电压或输出电流过冲的方法包括：确定闭环控制电路中处于开环状态的环路；获取闭环控制电路当前拍输出的发波控制值；将当前拍输出的发波控制值赋值给当前拍的开环输出值,其中,开环输出值为开环状态的环路的输出值；采用赋值后的当前拍的开环输出值,计算开环状态的环路下一拍的开环输出值。该抑制输出电压或输出电流过冲的方法能够降低电池电源的电压环路和电流环路在切换时的接管延时,避免电压环路和电流环路在切换时出现过冲的问题。(A method, a charging device and a medium for suppressing overshoot of an output voltage or an output current are disclosed. The method for inhibiting the overshoot of the output voltage or the output current comprises the following steps: determining a loop in an open loop state in a closed loop control circuit; acquiring a wave-sending control value output by a closed-loop control circuit at present; assigning the wave-sending control value output by the current beat to the open-loop output value of the current beat, wherein the open-loop output value is the output value of a loop in an open-loop state; and calculating the open-loop output value of the next beat of the loop in the open-loop state by adopting the assigned open-loop output value of the current beat. The method for restraining the overshoot of the output voltage or the output current can reduce the take-over time delay of the voltage loop and the current loop of the battery power supply during switching, and avoid the overshoot problem of the voltage loop and the current loop during switching.)

1. A method of suppressing overshoot of an output voltage or output current, comprising:

determining a loop in an open loop state in a closed loop control circuit;

acquiring a wave-sending control value output by the closed-loop control circuit at the current beat;

assigning the wave-sending control value output by the current beat to an open-loop output value of the current beat, wherein the open-loop output value is an output value of a loop in an open-loop state;

and calculating the open-loop output value of the next beat of the loop in the open-loop state by adopting the assigned open-loop output value of the current beat.

2. The method of claim 1, wherein determining a loop in the closed-loop control circuit that is in an open-loop state comprises:

determining a sampling time period according to the loop bandwidth;

acquiring a voltage sampling value or a current sampling value of each loop in the closed-loop control circuit in the sampling time period, wherein the loop comprises a voltage loop and a current loop, the voltage sampling value is acquired when the loop is the voltage loop, and the current sampling value is acquired when the loop is the current loop;

and if the voltage sampling values are all smaller than the voltage set value within a preset time in the sampling time period, or the current sampling values are all smaller than the current set value, determining that the voltage loop or the current loop is in an open loop state.

3. The method of claim 2, wherein determining the sampling period based on the loop bandwidth comprises:

selecting a time value from t ≧ 1/fg as a critical time value, wherein fg is the loop bandwidth;

and determining the sampling time period according to the critical time value.

4. The method according to claim 2, wherein the wave-sending control value is represented by a voltage value or a current value, and assigning the wave-sending control value output by the current beat to the open-loop output value of the current beat comprises:

when the loop in the open-loop state is the voltage loop, assigning the wave-sending control value output by the current beat and represented by the voltage value to the open-loop output value of the current beat;

and when the loop in the open-loop state is the current loop, assigning the wave-sending control value output by the current beat and represented by the current value to the open-loop output value of the current beat.

5. The method of claim 1, wherein the open-loop output value is derived based on a difference value, the difference value being an absolute difference value between an open-loop sample value and an open-loop setpoint value.

6. The method of claim 5, wherein the open loop output value is calculated using a PI loop compensator for loop compensation, derived from a clipped raw open loop output value Piout = Piout1+ k3 Err-k4 Err1, wherein Piout1 is the open loop output value for a previous beat, k3 is a first loop calculation coefficient, k4 is a second loop calculation coefficient, Err is the difference, and Err1 is the difference for a previous beat.

7. The method of any of claims 1-6, wherein the closed-loop control circuit comprises a dual-loop contention loop and an inner-outer loop nested loop.

8. A power supply circuit, wherein the power supply circuit is a closed loop control circuit, comprising:

the power supply circuit comprises a voltage ring and a current ring, wherein the voltage ring and the current ring are respectively used for controlling an output voltage value and an output current value, when the power supply circuit is electrified, one of the voltage ring and the current ring is in an open-loop state, and the other ring is in a closed-loop state, or the voltage ring and the current ring are in the open-loop state simultaneously;

the wave-sending control module is used for controlling wave sending by adopting the wave-sending control value output by the power circuit;

the voltage ring with the electric current ring all includes:

the loop compensator is used for compensating and calculating a closed loop of the loop;

the amplitude limiting module is used for carrying out amplitude limiting operation on the output value of the loop compensator to obtain an open-loop output value or a closed-loop output value;

the evaluation module is used for evaluating the output value of the current beat of the loop in the closed loop state for compensation calculation of the loop in the closed loop state of the next beat, or evaluating the wave-sending control value output by the current beat of the closed-loop control circuit to the open-loop output value, so as to calculate the open-loop output value of the next beat of the loop in the open-loop state by using the evaluated open-loop output value of the current beat, wherein the open-loop output value is the output value of the loop in the open-loop state;

and the switch is used for switching the voltage ring and the open-loop state and the closed-loop state of the current ring.

9. A charging device comprising a memory, a processor and computer readable instructions stored in the memory and executable on the processor, wherein the charging device further comprises a power supply circuit as claimed in claim 8, and wherein the processor when executing the computer readable instructions performs the steps of the method of suppressing output voltage or output current overshoot as claimed in any one of claims 1-7.

10. A computer readable storage medium storing computer readable instructions, which when executed by a processor implement the steps of a method of suppressing output voltage or output current overshoot as claimed in any one of claims 1-7.

Technical Field

The present disclosure relates to the field of electric vehicle charging, and more particularly, to a method, a charging device, and a medium for suppressing overshoot of an output voltage or an output current.

Background

With the rapid development of electric vehicle technology, the requirements on the safety of electric vehicles are also higher and higher. Particularly, when an electric vehicle is charged, the safety of a battery during charging of the electric vehicle needs to be ensured. Currently, battery charging power supplies are typically designed to include a voltage loop and a current loop. When the electric vehicle is charged, when the voltage loop and the current loop are switched, the output voltage or the output current of the battery power supply overshoots.

Disclosure of Invention

In view of the above, embodiments of the present application provide a method, a charging device, and a medium for suppressing overshoot of an output voltage or an output current, so as to solve the problem of overshoot of the output voltage or the output current of a battery power source when an electric vehicle is charged.

In a first aspect, an embodiment of the present application provides a method for suppressing overshoot of an output voltage or an output current, where the method includes:

determining a loop in an open loop state in a closed loop control circuit;

acquiring a wave-sending control value output by the closed-loop control circuit at the current beat;

assigning the wave-sending control value output by the current beat to an open-loop output value of the current beat, wherein the open-loop output value is an output value of a loop in an open-loop state;

and calculating the open-loop output value of the next beat of the loop in the open-loop state by adopting the assigned open-loop output value of the current beat.

The above aspect and any possible implementation further provides an implementation in which the determining a loop in a closed-loop control circuit that is in an open-loop state includes:

determining a sampling time period according to the loop bandwidth;

acquiring a voltage sampling value or a current sampling value of each loop in the closed-loop control circuit in the sampling time period, wherein the loop comprises a voltage loop and a current loop, the voltage sampling value is acquired when the loop is the voltage loop, and the current sampling value is acquired when the loop is the current loop;

and if the voltage sampling values are all smaller than the voltage set value within a preset time in the sampling time period, or the current sampling values are all smaller than the current set value, determining that the voltage loop or the current loop is in an open loop state.

The above aspect and any possible implementation further provides an implementation in which the determining a loop in a closed-loop control circuit that is in an open-loop state includes:

determining a sampling time period according to the loop bandwidth;

acquiring a voltage sampling value or a current sampling value of each loop in the closed-loop control circuit in the sampling time period, wherein the loops comprise a voltage loop and a current loop, the voltage sampling value is acquired when the loop is a voltage loop, and the current sampling value is acquired when the loop is a current loop;

and if the voltage sampling values are all smaller than the voltage set value within a preset time in the sampling time period, or the current sampling values are all smaller than the current set value, determining that the voltage loop or the current loop is in an open loop state.

The foregoing aspect and any possible implementation manner further provide an implementation manner, where the wave-sending control value is expressed by a voltage value or a current value, and assigning the wave-sending control value output by the current beat to an open-loop output value of the current beat includes:

when the loop in the open-loop state is the voltage loop, assigning the wave-sending control value output by the current beat and represented by the voltage value to the open-loop output value of the current beat;

and when the loop in the open-loop state is the current loop, assigning the wave-sending control value output by the current beat and represented by the current value to the open-loop output value of the current beat.

The above aspect and any possible implementation manner further provide an implementation manner, wherein the open-loop output value is obtained based on a difference value, and the difference value is an absolute value difference value between an open-loop sampling value and an open-loop given value.

The above-mentioned aspect and any possible implementation manner further provide an implementation manner, where the open-loop output value is calculated by using a PI loop compensator to perform a loop compensation calculation, and is obtained from a clipped original open-loop output value, where the original open-loop output value Piout = Piout1+ k3 Err-k4 Err1, where Piout1 is the open-loop output value of a previous beat, k3 is a first loop calculation coefficient, k4 is a second loop calculation coefficient, Err is the difference, and Err1 is the difference of the previous beat.

The above-described aspects and any possible implementations further provide an implementation in which the closed-loop control circuit includes a dual-loop contention loop and an inner-outer loop nested loop.

In a second aspect, an embodiment of the present application provides a power supply circuit, where the power supply circuit is a closed-loop control circuit, and includes:

the power supply circuit comprises a voltage ring and a current ring, wherein the voltage ring and the current ring are respectively used for controlling an output voltage value and an output current value, when the power supply circuit is electrified, one of the voltage ring and the current ring is in an open-loop state, and the other ring is in a closed-loop state, or the voltage ring and the current ring are in the open-loop state simultaneously;

the wave-sending control module is used for controlling wave sending by adopting the wave-sending control value output by the power circuit;

the voltage ring with the electric current ring all includes:

the loop compensator is used for compensating and calculating a closed loop of the loop;

the amplitude limiting module is used for carrying out amplitude limiting operation on the output value of the loop compensator to obtain an open-loop output value or a closed-loop output value;

the evaluation module is used for evaluating the output value of the current beat of the loop in the closed loop state for compensation calculation of the loop in the closed loop state of the next beat, or evaluating the wave-sending control value output by the current beat of the closed-loop control circuit to the open-loop output value, so as to calculate the open-loop output value of the next beat of the loop in the open-loop state by using the evaluated open-loop output value of the current beat, wherein the open-loop output value is the output value of the loop in the open-loop state;

and the switch is used for switching the voltage ring and the open-loop state and the closed-loop state of the current ring.

In a third aspect, embodiments of the present application provide a charging device, including a memory, a processor, and computer readable instructions stored in the memory and executable on the processor, the charging device further including a power supply circuit as described in the second aspect, and the processor executing the computer readable instructions executes the steps of the method for suppressing overshoot of the output voltage or output current as described in the first aspect.

In a fourth aspect, embodiments of the present application provide a computer-readable storage medium storing computer-readable instructions, which, when executed by a processor, implement the steps of the method for suppressing output voltage or output current overshoot as described in the first aspect.

In the embodiment of the application, firstly, a loop in an open-loop state in a closed-loop control circuit is determined, so that loop compensation calculation can be carried out on the loop in the open-loop state; then, acquiring a wave-emitting control value output by the closed-loop control circuit at the current beat, and assigning the wave-emitting control value output by the current beat to the open-loop output value of the current beat so as to enable the wave-emitting control value output by the current beat to replace the loop compensation effect of the loop in the closed-loop state; and finally, calculating the open-loop output value of the next beat of the loop in the open-loop state by adopting the assigned open-loop output value of the current beat, so that the loop can calculate the open-loop output value of the next beat according to the assigned open-loop output value of the current beat in the open-loop state, the compensation effect of the closed-loop is achieved, the take-over time delay of the voltage loop and the current loop of the battery power supply during switching is reduced, and the overshoot problem of the voltage loop and the current loop during switching is avoided.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without inventive labor.

FIG. 1 is a schematic block diagram of a dual ring contention loop in an embodiment of the present application;

FIG. 2 is a flow chart of a method of suppressing overshoot of an output voltage or output current according to an embodiment of the present application;

FIG. 3 is a schematic block diagram of an inner and outer loop nested loop in an embodiment of the present application;

FIG. 4 is a schematic block diagram of an improved dual-loop contention loop in an embodiment of the present application;

FIG. 5 is a schematic block diagram of an improved inner and outer loop nested loop in an embodiment of the present application;

fig. 6 is a schematic block diagram of a dual open loop state of a voltage loop and a current loop during a soft start process according to an embodiment of the present application;

fig. 7 is a schematic block diagram of a charging device according to an embodiment of the present application.

Detailed Description

For better understanding of the technical solutions of the present application, the following detailed descriptions of the embodiments of the present application are provided with reference to the accompanying drawings.

It should be understood that the embodiments described are only a few embodiments of the present application, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

The terminology used in the embodiments of the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used in the examples of this application and the appended claims, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

It should be understood that the term "and/or" as used herein is merely a field that describes the same of an associated object, meaning that three relationships may exist, e.g., A and/or B, may indicate: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" herein generally indicates that the former and latter related objects are in an "or" relationship.

It should be understood that although the terms first, second, third, etc. may be used to describe preset ranges, etc. in the embodiments of the present application, these preset ranges should not be limited to these terms. These terms are only used to distinguish preset ranges from each other. For example, the first preset range may also be referred to as a second preset range, and similarly, the second preset range may also be referred to as the first preset range, without departing from the scope of the embodiments of the present application.

The word "if" as used herein may be interpreted as "at … …" or "when … …" or "in response to a determination" or "in response to a detection", depending on the context. Similarly, the phrases "if determined" or "if detected (a stated condition or event)" may be interpreted as "when determined" or "in response to a determination" or "when detected (a stated condition or event)" or "in response to a detection (a stated condition or event)", depending on the context.

With the continuous development and progress of power supply technology, the output performance index and safety requirements of the power supply in practical application scenes are higher and higher. Particularly, in the charging of an electric vehicle, in order to protect the safety of the battery power supply during charging, it is necessary to suppress overshoot of the output voltage and output current of the battery power supply. Where overshoot refers to the transition from one value to another, the instantaneous value of any parameter exceeds its final steady state value. In the charging scenario of an electric vehicle, the overshoot of the output voltage or output current, i.e. its instantaneous value, exceeds its steady-state values (voltage setpoint and current setpoint). When the output voltage or output current overshoots, electronic components in the battery power supply can be caused to fail or even be damaged, and a series of safety problems are caused.

Closed-loop control is a feedback control in which a sampled value of an output value is compared with a desired set value, thereby generating an offset signal, and the offset signal is used to perform a regulation control so that the output value approaches the desired set value as closely as possible. The current closed-loop control circuit generally comprises a voltage loop and a current loop. In the charging process of the electric automobile, when the voltage ring is in an open-loop state, the current ring is in a closed-loop state; when the voltage ring is in a closed loop state, the current ring is in an open loop state; in particular, in some special phases, there may be situations where both the voltage and current loops are in an open loop state. It can be understood that when the voltage loop or the current loop is in the open loop state, since the loop compensation calculation of the closed loop is not performed, the output voltage of the voltage loop or the output current of the current loop will reach the maximum value, and once the voltage loop or the current loop is switched from the voltage loop to the current loop or from the current loop to the voltage loop pair, the voltage loop or the current loop needs to be gradually reduced from the maximum value to the voltage set value or the current set value through the loop compensation calculation of the closed loop. Due to the time delay of the connection pipe, the output voltage of the voltage loop or the output current of the current loop has a large overshoot peak in the time period from the maximum value to the voltage set value or the current set value.

Hereinafter, a case where an overshoot of the output voltage loop or the output current occurs during the charging of the electric vehicle will be described using the dual-loop competition loop as an example.

Fig. 1 is a schematic block diagram of a dual-ring contention loop in an embodiment of the present application. As shown in fig. 1, the dual-loop contention loop includes a voltage loop and a current loop, where the output voltage is controlled by the voltage loop alone, the output current is controlled by the current loop alone, and finally, the output result Dout is taken as an actual control pulse-generating value after being reduced (by MIN operation) by comparing the output results of the voltage loop and the current loop, for example, controlling an EPWM (enhanced pulse width modulation) duty ratio. In the process of double-loop competition, when the double-loop competition works in a voltage loop or a current loop, the other loop is in an open loop state.

For the voltage loop, a voltage sampling value V _ samp, a voltage given value Vref, an absolute value difference value between the voltage given value and the voltage sampling value is a difference value V _ Err, and the difference value V _ Err is an input quantity of the voltage loop compensator. The compensator may be a PI loop compensator. Specifically, the transfer function of the PI loop compensator digitization is V _ Piout = V _ Piout1+ kv 3V _ Err-kv 4V _ Err1, where V _ Piout is a clipped value of the current beat voltage loop compensator output, kv3 and kv4 are both loop calculation coefficients (known), and V _ Piout1 is an output value of the previous beat loop compensator, and is applied to the current beat voltage loop compensation calculation. It is to be understood that, in the assignment phase, V _ Piout1= V _ Piout, indicating the output of the voltage loop of the previous beat when the output of the voltage loop of the current beat is calculated as the next beat, and similarly, V _ Err1= V _ Err, indicating the difference of the voltage loop of the previous beat when the difference of the current beat is calculated as the difference of the next beat.

For the current loop, specifically, a current sampling value I _ samp, a current given value Iref, an absolute value difference between the current given value and the current sampling value is a difference value I _ Err, and the difference value I _ Err is an input quantity of the current loop compensator. The compensator may be a PI loop compensator. Specifically, the transfer function of the PI loop compensator digitization is I _ Piout = I _ Piout1+ ki 3I _ Err-ki 4I _ Err1, where I _ Piout is the clipped value of the current loop compensator output of the current beat, ki3 and ki4 are both loop calculation coefficients (known), and I _ Piout1 is the output value of the previous beat loop compensator, and is applied to the current loop compensation calculation of the current beat. It is to be understood that, in the assignment phase, I _ Piout1= I _ Piout, indicating the output of the current loop of the previous beat when the output of the current loop of the current beat is calculated as the next beat, and similarly, I _ Err1= I _ Err, indicating the difference of the current loop of the previous beat when the difference of the current beat is calculated as the difference of the next beat.

In the double-loop competition process, when a loop is in an open loop state, the loop calculation result of the loop reaches a maximum value. For example, when the current loop is in an open loop state, the current loop reaches a saturated maximum output by integration. When the closed-loop control circuit is switched from the voltage loop to the current loop, the current loop needs to gradually decrease from the maximum value to the desired current set value because the output result of the current loop is at the maximum value. During this period of gradual droop, the current will always be in an overshoot state. Particularly, when the electric vehicle is charged, when the output voltage of the voltage loop or the output current of the current loop is slightly high, a peak of a large charging current is caused, and a large problem is brought to the safety of charging the electric vehicle.

Fig. 2 is a flowchart of a method for suppressing overshoot of an output voltage or an output current according to an embodiment of the present application. The method for restraining the overshoot of the output voltage or the output current can be applied to the electric automobile, and the overshoot of the output voltage or the output current can be restrained when the electric automobile is charged. As shown in fig. 2, the method for suppressing overshoot of the output voltage or the output current includes the following steps:

s10: a loop in the closed-loop control circuit that is in an open-loop state is determined.

The closed loop control circuit is a feedback control circuit. The feedback control circuit compares the sampled value of the circuit output value with a desired set value to generate a deviation value, and the deviation value is used for regulation control to enable the circuit output value to be as close to the desired set value as possible, wherein the set value can be a voltage set value or a current set value. In a closed loop control circuit, not all loops can be in a closed loop state. For example, in a closed-loop control circuit with a double-loop competition loop structure, when a voltage loop is in a closed-loop state, a current loop is in an open-loop state; when the voltage ring is in an open-loop state, the current ring is in a closed-loop state. It will be appreciated that in a closed loop control circuit, not all loops can implement loop compensation calculations in the closed loop state.

In one embodiment, since the loop in the open loop state cannot perform the loop compensation calculation as in the closed loop state, the output value will reach the maximum value. The loop in the open loop state is a main loop causing overshoot of the output voltage or the output current when the electric vehicle is charged. In this embodiment, when the electric vehicle is charged, which loops in the closed-loop control circuit are in the open-loop state during the charging process are determined, so that loop compensation calculation can be performed on the loops in the open-loop state.

S20: and acquiring a wave sending control value output by the closed-loop control circuit at the current beat.

The closed-loop control circuit obtains a voltage/current sample value as a voltage loop/current loop input, an execution flow from the voltage/current sample value to the output of the wave-sending control value is one beat, the current beat is one beat of the execution flow, and the last beat is the last execution flow relative to the current beat.

The wave control value is an output value for controlling, for example, the duty ratio of the EPWM. The wave-emitting control value can determine the duty ratio of the EPWM so as to output a proper waveform and achieve the effect of accurately controlling the voltage/current. In this embodiment, the loop compensation calculation can be performed on the loop in the open-loop state by using the information, so that the loop in the open-loop state can receive the information on the voltage/current output of the current beat in time, for example, the loop compensation calculation in the closed loop is realized, and when the loop is in the open-loop state, the effect similar to the closed-loop feedback is still realized.

S30: and assigning the wave-sending control value to the open-loop output value of the current beat, wherein the open-loop output value is the output value of the loop in the open-loop state.

It is understood that the ripple control value is an output of the closed-loop control circuit, and an output of the voltage loop and the current loop included in the closed-loop control circuit is an open-loop output value when the voltage loop and the current loop are in an open-loop state.

In one embodiment, when the closed-loop control circuit is in the current beat, the loop in the open-loop state is different from the closed-loop, the closed-loop compensation calculation cannot be realized, and the open-loop output value of the closed-loop control circuit reaches the maximum value. For example, a current loop in an open loop state that reaches a saturated maximum output by integration. It is understood that when the open-loop output value is always at the maximum value, if the closed-loop control circuit switches the loop in the open-loop state to the closed-loop state, a certain time is required for the output value at the maximum value to fall to a desired given value. During this time period, the output voltage or output current will have problems with overshoot. In this embodiment, the wave-sending control value is assigned to the open-loop output value of the current beat, so that the closed-loop compensation calculation can be timely implemented on the loop in the open-loop state by using the information about the voltage/current output of the current beat attached to the wave-sending control value at each beat, so that the loop in the open-loop state can timely update the open-loop output value and act on the loop compensator to achieve the purpose of compensation calculation.

S40: and calculating the open-loop output value of the next beat of the loop in the open-loop state by adopting the assigned open-loop output value of the current beat.

It can be understood that if the open loop output value is at the maximum, then the loop compensation by the loop is not effective. In the embodiment of the application, the assigned open-loop output value of the current beat, namely the open-loop output value updated according to the wave-sending control value, is used as one of the calculation parameters of the open-loop output value of the next beat of the loop in the open-loop state, and the effect of loop compensation calculation can be realized according to the updated open-loop output value of each beat. In the embodiment of the present application, the open-loop output value of the next beat of the loop in the open-loop state is calculated by using the assigned open-loop output value of the current beat in each beat, and the open-loop output value can be better updated, so that the problem of take-over delay of the voltage/current loop can be eliminated when the closed-loop control circuit switches the open-loop state and the closed-loop state of the loop, and the voltage overshoot or the circuit overshoot of the voltage/current loop can be suppressed.

In the embodiment of the application, firstly, a loop in an open-loop state in a closed-loop control circuit is determined, so that loop compensation calculation can be carried out on the loop in the open-loop state; then, acquiring a wave-emitting control value output by the closed-loop control circuit at the current beat, and assigning the wave-emitting control value output by the current beat to the open-loop output value of the current beat so as to enable the wave-emitting control value output by the current beat to replace the loop compensation effect of the loop in the closed-loop state; and finally, calculating the open-loop output value of the next beat of the loop in the open-loop state by adopting the assigned open-loop output value of the current beat, so that the loop can calculate the obtained open-loop output value of the next beat according to the assigned open-loop output value of the current beat in the open-loop state, the compensation effect of the closed-loop is achieved, the take-over time delay of the voltage loop and the current loop of the battery power supply during switching is reduced, and the overshoot problem of the voltage loop and the current loop during switching is avoided.

Further, in step S10, that is, in the step of determining the loop in the open loop state in the closed-loop control circuit, the method specifically includes the following steps:

s11: the sampling period is determined according to the loop bandwidth.

The loop bandwidth refers to a frequency range in which the loop can stably operate. The voltage loop bandwidth refers to the frequency range in which the voltage loop can stably work, and the current loop is similar.

In an embodiment, the sampling of the voltage/current loop output values is determined in dependence on the loop bandwidth. The loop bandwidth can reflect whether the loop works stably, and the sampling time period capable of sampling is determined by using the loop bandwidth, so that normal work such as compensation calculation of the loop can be guaranteed in the sampling time period of the sampling, and the voltage loop/current loop output value obtained in the sampling time period is determined to be reliable and effective.

S12: and acquiring a voltage sampling value or a current sampling value of each loop in the closed-loop control circuit in a sampling time period, wherein the loops comprise a voltage loop and a current loop, and when the loops are voltage loops, acquiring the voltage sampling value, and when the loops are current loops, acquiring the current sampling value.

It will be appreciated that the voltage output values are sampled for the voltage loop and the current output values are sampled for the current loop. Because it is unknown that each loop in the closed-loop control circuit is in a closed-loop state or an open-loop state, the voltage loop and the current loop should be sampled simultaneously, so as to determine the open-loop state of each loop according to the sampling value. The voltage sampling value or the current sampling value acquired in the sampling time period is acquired when the loop works stably, so that the acquired voltage sampling value or the acquired current sampling value can be ensured to be reliable and effective, and the condition of misjudgment on the final judgment result can be avoided.

S13: and if the voltage sampling values are smaller than the voltage set value within a preset time or the current sampling values are smaller than the current set value within a sampling time period, determining that the voltage loop or the current loop is in an open loop state.

In one embodiment, for a closed loop control circuit comprising a dual loop structure (voltage loop and current loop), a loop in an open loop state has its loop output below a given output for a period of time; and in a closed loop, the loop output is generally higher than the given output. It will be appreciated that in an open loop, which may experience integral saturation, it takes a long time for the loop to reach a given output. In the embodiment of the application, a voltage sampling value/a current sampling value is compared with a corresponding voltage given value/a current given value within a sampling time period, and if the voltage sampling value/the current sampling value within a preset time is smaller than the voltage given value or the current sampling value is smaller than the current given value within the sampling time period, it is determined that a voltage loop or a current loop is in an open loop state.

In steps S11-S13, a specific implementation of determining a loop in an open-loop state in a closed-loop control circuit is provided, and by using a phenomenon that the loop in the open-loop state is subjected to integral saturation, and comparing a voltage sampled value/current sampled value with a voltage given value/current given value corresponding to the voltage sampled value/current sampled value within a sampling time, the loop in which the voltage sampled value/current sampled value is smaller than the voltage given value or the current sampled value is smaller than the current given value within a preset time within the sampling time period can be determined as an open-loop state.

Further, in step S11, that is, in the step of determining the sampling time period according to the loop bandwidth, the method specifically includes the following steps:

s111: and selecting a time value from t ≧ 1/fg as a critical time value, wherein fg is the loop bandwidth.

The loop bandwidth is a frequency range that enables the loop to operate stably and to realize loop control. In one embodiment, the sampling time period t can be selected from t ≧ 1/fg, so that normal loop compensation calculation of the closed-loop control circuit can be guaranteed, and the closed-loop control circuit can operate stably.

S112: and determining a sampling time period according to the critical time value.

In one embodiment, the critical time value is selected to allow stable operation of the closed loop control circuit. On the premise of stable operation, the acquired voltage output value/current output value has no large error, and the data has high reliability. After the critical time value is determined, the interval range from 0 time to the critical time value may be used as the sampling time period from 0 time. And when the voltage loop sampling values are smaller than the voltage set value or the current loop sampling values are smaller than the current set value within a preset time within the sampling time period, determining that the voltage loop or the current loop is in an open loop state. It can be understood that, in a loop in an open-loop state, the loop may have an integral saturation phenomenon, the loop may take a long time to reach a given output, and during this period, there is a case that voltage loop sampling values are all smaller than a voltage given value or current loop sampling values are all smaller than a current given value within a preset time.

In steps S111-S112, specific embodiments of how to determine the sampling time period are provided, a time value can be selected from t ≧ 1/fg as the critical time value, and the interval range from 0 time to the critical time value is taken as the sampling time period from 0 time. Therefore, normal loop compensation calculation of the closed-loop control circuit can be guaranteed, and the closed-loop control circuit can stably operate. The data reliability of the sampled output voltage value or output current value is high, and after the situation that the voltage loop sampling values are smaller than the voltage set value or the current loop sampling values are smaller than the current set value within a preset time exists in the sampling time period is determined, the voltage loop or the current loop can be accurately determined to be in an open loop state.

Further, the wave-generating control value is expressed by a voltage value or a current value.

It will be appreciated that the closed loop control circuit comprises a current loop and a voltage loop, the output value of each loop comprising a voltage value or a current value. The voltage value and the current value can be converted with each other, only the output representation modes are different, and when the loop compensation calculation is actually performed on the loop in the open loop state or the loop in the closed loop state, the corresponding representation mode is adopted for calculation according to the actual condition of the loop (for example, the loop is a voltage loop or a current loop). In this embodiment, the expression mode of the wave-sending control value is not limited, the wave-sending control value may be expressed in a plurality of modes, and the values expressed in the various modes may be converted to each other.

Further, in step S30, the step of assigning the launch control value to the open-loop output value of the current beat specifically includes the following steps:

s31: and when the loop in the open-loop state is a voltage loop, assigning the wave-sending control value represented by the voltage value to the open-loop output value of the current beat.

S32: and when the loop in the open-loop state is a current loop, assigning the wave-sending control value represented by the current value to the open-loop output value of the current beat.

The closed-loop control circuit comprises a voltage loop and a current loop, and when the wave-sending control value is assigned to the open-loop output value of the current beat, the assignment of the wave-sending control value can be completed in a voltage value or current value representing mode according to the actual condition that the loop is a voltage loop or a current loop. Therefore, the wave-sending control value can be adjusted and converted in advance, the same expression mode as the original open-loop output value is kept after the value is assigned to the currently-shot open-loop output value, and loop compensation calculation can be rapidly completed on the loop in the open-loop state.

Further, the open-loop output value is obtained based on a difference value, which is an absolute value difference value between the open-loop sampling value and the open-loop given value.

It is understood that, in the closed-loop control circuit, in addition to the loop in the closed-loop state using the difference value in the compensation calculation, in the embodiment of the present application, the difference value is also calculated for the loop in the open-loop state, where the difference value is the absolute value difference between the open-loop sampling value and the open-loop given value.

It is understood that the present application also implements loop compensation calculations for loops in an open loop state. The wave-sending control value is assigned to the open-loop output value of the current beat, the open-loop sampling value is influenced, and the difference value obtained based on the open-loop sampling value is updated along with the beat number, so that when the loop in the open-loop state utilizes the wave-sending control value to realize loop compensation calculation, the data accuracy of the parameters during the compensation calculation can be ensured.

Further, the open loop output value may specifically be calculated by performing loop compensation using a PI loop compensator, and the open loop output value is obtained from an original open loop output value after being limited, where the original open loop output value Piout = Piout1+ k3 Err-k4 Err1, where Piout1 is an open loop output value of a previous beat, k3 is a first loop calculation coefficient, k4 is a second loop calculation coefficient, Err is a difference value, and Err1 is a difference value of the previous beat.

Further, the loop compensator may also be another type of compensator, and is not limited herein.

Where k3, k4 are known parameters, and are related to the selected compensator, they can be represented as kv3, kv4 in the loop compensation calculation of the current loop, and ki3, ki4 in the loop compensation calculation of the current loop. It will be appreciated that the calculation of the raw open loop output value includes the open loop output value for the previous beat, the difference between the current beat and the previous beat, and after clipping, the loop output value is made as close to the open loop setpoint as possible. In the embodiment of the application, the PI loop compensator can be adopted to well complete loop compensation calculation, so that the open loop output value is closer to the open loop given value after the loop compensation calculation.

Further, the closed-loop control circuit may include an inner and outer loop nested loop, etc., in addition to the dual-loop contention loop.

Fig. 3 is a schematic block diagram of an inner and outer loop nested loop in an embodiment of the present application. As shown in fig. 3, the inner and outer loop nested loop includes a voltage outer loop and a current inner loop, wherein the output voltage of the voltage outer loop and the set current value (Iset) of the current inner loop are reduced (MIN operation is adopted) to be used as the given current value (Iref) of the current inner loop to control the actually output current value, and the actually output current value is used as the actually output control ripple value, such as controlling the EPWM duty ratio. When the electric automobile is charged, the battery power supply works in the current inner ring (the current inner ring is in a closed loop state), the voltage outer ring is in an open loop state, and the voltage outer ring is in saturated output. At this time, once the battery power source exits from the current inner ring, such as during unloading or heavy-load switching light load, the voltage outer ring needs to be gradually reduced from the maximum value to the current voltage set value. Due to the time delay of the voltage outer loop, the output voltage has a large overshoot peak in the period of time.

Specifically, for the voltage outer ring, there are a voltage sampling value V _ samp, a voltage given value Vref, an absolute value difference between the voltage given value and the voltage sampling value is a difference value V _ Err, and the difference value V _ Err is an input amount of the voltage outer ring compensator. The compensator may be a PI loop compensator. Specifically, the transfer function of the PI loop compensator digitization is V _ Piout = V _ Piout1+ kv 3V _ Err-kv 4V _ Err1, where V _ Piout is a clipped value of the current beat voltage outer loop compensator output, kv3 and kv4 are loop calculation coefficients (known), and V _ Piout1 is an output value of the previous beat loop compensator, and is applied to the current beat voltage outer loop compensation calculation. It is to be understood that, in the assignment phase, V _ Piout1= V _ Piout, indicating the output of the voltage outer loop at the current beat as the output of the voltage outer loop at the next beat, and similarly, V _ Err1= V _ Err, indicating the difference of the voltage outer loop at the current beat as the difference of the previous beat at the next beat.

For the current inner loop, specifically, a current sampling value I _ samp, a current given value Iref, an absolute value difference between the current given value and the current sampling value is a difference value I _ Err, and the difference value I _ Err is an input quantity of the current inner loop compensator. The compensator may be a PI loop compensator. Specifically, the transfer function of the PI loop compensator digitization is I _ Piout = I _ Piout1+ ki 3I _ Err-ki 4I _ Err1, where I _ Piout is the clipped value of the current inner loop compensator output of the current beat, ki3 and ki4 are both loop calculation coefficients (known), and I _ Piout1 is the output value of the previous beat loop compensator, and is applied to the current inner loop compensation calculation of the current beat. It is to be understood that, in the assignment phase, I _ Piout1= I _ Piout, indicating the output of the current inner loop of the previous beat when the output of the current inner loop of the current beat is calculated as the next beat, and similarly, I _ Err1= I _ Err, indicating the difference of the current inner loop of the previous beat when the difference of the current beat is calculated as the next beat. It can be seen that, for a closed-loop control circuit including a voltage outer loop and a current inner loop, no matter a double-loop control structure or an inner and outer loop nested structure is adopted, the problem of overshoot of the output voltage or the output current of the battery power supply exists.

Taking the two closed-loop control circuits as examples, the application provides specific embodiments for realizing suppression of overshoot of output voltage or output current of a battery power supply in a double-loop control loop and an inner-outer loop nested loop respectively.

Fig. 4 is a schematic block diagram of an improved dual-loop contention loop in an embodiment of the present application.

Fig. 4 is compared with fig. 1, and fig. 4 adds a switch Sw0 and a switch Sw1 in the voltage loop and the current loop, respectively. Wherein each switch comprises two signal states, signal 1 and signal 0. Wherein, signal 1 indicates that the current loop is in an open loop state, and signal 0 indicates that the current loop is in a closed loop state.

When the switch Sw0 is 1 when the voltage loop is in the open loop state, the output result Dout is assigned to V _ Piout1 and applied to the voltage loop calculation for the next beat. It should be noted that, in the case that the voltage loop calculation of Dout assigned to V _ Piout1 and applied to the next beat is result-oriented, the actual implementation flow may be: the output result Dout is assigned to V _ Piout, which is assigned as V _ TrueOut to V _ Piout1 when the next beat of voltage loop calculation is performed, i.e. the value of V _ Piout1 finally used for the calculation is equal to the value of the output result Dout. When the loop is in an open loop state, V _ true indicates a value obtained by assigning the output result Dout to V _ true, that is, the real output of the voltage loop, and V _ true 1= V _ true when the voltage loop calculation of the next beat is performed, that is, V _ true 1 indicates that V _ true is assigned by V _ true. When the switch Sw0 is 0 when the voltage loop is in the closed loop state, the voltage loop assigns V _ Piout to V _ Piout1 (V _ true = V _ Piout, V _ Piout1= V _ true in the closed loop state) for the next beat of voltage loop calculation. It should be noted that V _ TrueOut may be only a concept (mainly used for distinguishing real output of the voltage ring), and is not necessarily used for actual assignment operation, and the solution of the present application may also be implemented only by assignment calculation of Dout, V _ Piout, and V _ Piout 1.

The concepts of V _ Piout and V _ Piout1 are relative, and V _ Piout becomes V _ Piout1 when V _ Piout is applied to the next beat voltage loop calculation. The presence of V _ Piout1 should be referenced to V _ Piout, by which V _ Piout1 is actually determined.

Similarly, when the switch Sw1 is 1 also when the current loop is in the open loop state, the output result Dout is assigned to I _ Piout1 for the current loop calculation of the next beat. When the switch Sw1 is 0 when the current loop is in the closed loop state, the current loop assigns I _ Piout to I _ Piout1 for the current loop calculation for the next beat.

The improved double-loop competition loop can be understood that the control wave sending value is assigned to the loop calculation in the open-loop state, the open-loop calculation is made to take the control wave sending value Dout as the output result of the last beat to participate in the calculation, the condition that the loop output value is at the maximum value due to the fact that the voltage loop/current loop is in the open-loop state for a long time is avoided, the problem of connection delay of the voltage loop/current loop is solved, and voltage overshoot or current overshoot generated by the voltage loop/current loop can be effectively inhibited.

Fig. 5 is a schematic block diagram of an improved inner and outer loop nested loop in an embodiment of the present application.

As shown in fig. 5, the improved inner and outer loop nested loop includes a voltage outer loop and a current inner loop.

The inner-outer loop nested loop comprises a voltage outer loop and a current inner loop, wherein after the output voltage of the voltage outer loop and the set current value (Iset) of the current inner loop are reduced (MIN operation is adopted), the output voltage and the set current value are used as the given current value (Iref) of the current inner loop to control the actually output current value, and the actually output current value is used as the actual control wave sending value, such as EPWM duty ratio control.

Fig. 5 compares to fig. 2, with the addition of switch Sw2 in the voltage outer loop of fig. 5. Wherein the switch Sw2 includes two signal states, signal 1 and signal 0. Wherein, the signal 1 indicates that the current voltage outer ring is in an open-loop state, and the signal 0 indicates that the current voltage outer ring is in a closed-loop state.

When the voltage outer ring is in an open-loop state, the switch Sw2 is 1, and at this time, the given current value Iref is converted into a voltage value, and then is assigned to the V _ piout1 of the voltage outer ring, and is applied to the voltage outer ring calculation of the next beat. The assignment process may specifically be: the given current value Iref is converted into a voltage value and then assigned to V _ Piout, and when the voltage outer loop calculation of the next beat is carried out, the V _ Piout is assigned to V _ Piout1 through V _ TrueOut, namely, the value of V _ Piout1 finally used for calculation is equal to the voltage value converted by the given current value Iref. When the voltage outer ring is in an open-loop state, V _ true out represents a value obtained by assigning a voltage value converted by using a current given value Iref to V _ Piout, namely, the real output of the voltage outer ring, and when the voltage outer ring calculation of the next beat is performed, V _ Piout1= V _ true out, namely, V _ Piout1 is assigned by V _ true out. When the switch Sw2 is 0 when the voltage outer loop is in the closed loop state, the voltage outer loop assigns V _ Piout to V _ Piout1, which is used for the next beat of voltage outer loop calculation.

The improved inner and outer loop nested loop is characterized in that a voltage value converted by a current given value Iref is assigned to a loop calculation in an open loop state, the voltage value converted by the current given value Iref is used as an output result of the last beat in the open loop voltage calculation, the condition that the loop output value is at the maximum value due to the fact that the voltage loop/current loop is in the open loop state for a long time is avoided, the problem of connection delay of the voltage loop/current loop is solved, and voltage overshoot or current overshoot generated by the voltage loop/current loop can be effectively inhibited.

Fig. 6 is a schematic block diagram of a dual ring-open state of a voltage ring and a current ring during a soft start process according to an embodiment of the present application. As shown in fig. 6, compared with fig. 4, in fig. 6, the voltage loop and the current loop are both in an open loop state, i.e., Sw0=1, Sw1= 1; further, after the MIN operation, a soft start, wave-limiting step is included. It will be appreciated that in practical applications, particularly during charging of an electric vehicle, the battery power supply may be provided with a soft start strategy. The soft start strategy can control the wave sending value to be gradually opened according to certain steps, wherein in the process of sending waves to be taken over to a loop, the situation that the voltage loop and the current loop are both in an open loop state exists. In the embodiment of the application, the switches Sw0 and Sw1 are added, when the voltage ring and the current ring are both in an open-loop state, the output result Dout of the closed-loop control circuit can be assigned to the current beat loop output of the voltage ring and the current ring, and the current ring can participate in the loop compensation calculation of the next beat voltage ring and the current ring, so that the problem of take-over delay of the voltage ring/current ring is solved, and voltage overshoot or current overshoot generated by the voltage ring/current ring in the soft start process can be remarkably avoided.

In the embodiment of the application, firstly, a loop in an open-loop state in a closed-loop control circuit is determined, so that loop compensation calculation can be carried out on the loop in the open-loop state; then, acquiring a wave-emitting control value output by the closed-loop control circuit at the current beat, and assigning the wave-emitting control value output by the current beat to the open-loop output value of the current beat so as to enable the wave-emitting control value output by the current beat to replace the loop compensation effect of the loop in the closed-loop state; and finally, calculating the open-loop output value of the next beat of the loop in the open-loop state by adopting the assigned open-loop output value of the current beat, so that the loop can calculate the obtained open-loop output value of the next beat according to the assigned open-loop output value of the current beat in the open-loop state, the compensation effect of the closed-loop is achieved, the take-over time delay of the voltage loop and the current loop of the battery power supply during switching is reduced, and the overshoot problem of the voltage loop and the current loop during switching is avoided.

Furthermore, in the embodiment of the present application, by using the phenomenon that the loop in the open-loop state may have integral saturation, and comparing the voltage sampling value/current sampling value with the voltage given value/current given value corresponding thereto in the sampling time, the loop in which the voltage sampling value/current sampling value in a preset time existing in the sampling time period is smaller than the voltage given value or the current sampling value is smaller than the current given value can be determined as the open-loop state.

Furthermore, in the embodiment of the application, a time value can be selected from t ≧ 1/fg as a critical time value, and an interval range from 0 time to the critical time value is taken as a sampling time period from 0 time. Therefore, normal loop compensation calculation of the closed-loop control circuit can be guaranteed, and the closed-loop control circuit can stably operate. The data reliability of the sampled output voltage value or output current value is high, and after the situation that the voltage loop sampling values are smaller than the voltage set value or the current loop sampling values are smaller than the current set value within a preset time exists in the sampling time period is determined, the voltage loop or the current loop can be accurately determined to be in an open loop state.

Further, when the wave-sending control value is assigned to the open-loop output value of the current beat, the assignment of the wave-sending control value can be completed in a voltage value or current value representing mode according to the actual condition that the loop is a voltage loop or a current loop. Therefore, the wave-sending control value can be adjusted and converted in advance, the same expression mode as the original open-loop output value is kept after the value is assigned to the currently-shot open-loop output value, and loop compensation calculation can be rapidly completed on the loop in the open-loop state.

Furthermore, the wave-sending control value is assigned to the open-loop output value of the current beat, the open-loop sampling value is influenced, and correspondingly, the difference value obtained based on the open-loop sampling value is updated along with the beat number, so that when the loop in the open-loop state utilizes the wave-sending control value to realize loop compensation calculation, the data accuracy of the parameters during the compensation calculation can be ensured.

Furthermore, the PI loop compensator can well complete loop compensation calculation, so that the open loop output value is closer to the open loop given value after the loop compensation calculation.

It should be understood that, the sequence numbers of the steps in the foregoing embodiments do not imply an execution sequence, and the execution sequence of each process should be determined by its function and inherent logic, and should not constitute any limitation to the implementation process of the embodiments of the present application.

The embodiment of the present application further provides a power circuit, which is a closed-loop control circuit, including:

and the voltage ring and the current ring are respectively used for controlling an output voltage value and an output current value, wherein when the power circuit is electrified, one of the voltage ring and the current ring is in an open-loop state, and the other ring is in a closed-loop state, or the voltage ring and the current ring are in an open-loop state at the same time.

And the wave-sending control module is used for controlling wave sending by adopting the wave-sending control value output by the power circuit.

Voltage ring and electric current ring all include:

and the loop compensator is used for compensation calculation of a closed loop of the loop.

And the amplitude limiting module is used for carrying out amplitude limiting operation on the output value of the loop compensator to obtain an open-loop output value or a closed-loop output value.

And the assignment module is used for assigning the output value of the current beat of the loop in the closed loop state to the compensation calculation of the loop in the closed loop state of the next beat, or assigning the wave-sending control value output by the current beat of the closed-loop control circuit to the open-loop output value, so as to calculate the open-loop output value of the next beat of the loop in the open loop state by adopting the assigned open-loop output value of the current beat, wherein the open-loop output value is the output value of the loop in the open loop state.

And the switch is used for switching between the open-loop state and the closed-loop state of the voltage loop and the current loop.

Fig. 7 is a schematic block diagram of a charging device according to an embodiment of the present application.

As shown in fig. 7, the present application further provides a charging device, which includes a memory, a processor, and computer readable instructions stored in the memory and executable on the processor, and the charging device further includes a power circuit as in the above embodiment, the power circuit is disposed in a charging module of the charging device, and the processor executes the computer readable instructions to perform the following steps:

determining a loop in an open loop state in a closed loop control circuit;

acquiring a wave-sending control value output by a closed-loop control circuit at present;

assigning the wave-sending control value output by the current beat to the open-loop output value of the current beat, wherein the open-loop output value is the output value of a loop in an open-loop state;

and calculating the open-loop output value of the next beat of the loop in the open-loop state by adopting the assigned open-loop output value of the current beat.

Further, the processor, when executing the computer readable instructions, performs the following steps:

the sampling period is determined according to the loop bandwidth.

And acquiring a voltage sampling value or a current sampling value of each loop in the closed-loop control circuit in a sampling time period, wherein the loops comprise a voltage loop and a current loop, and when the loops are voltage loops, acquiring the voltage sampling value, and when the loops are current loops, acquiring the current sampling value.

And if the voltage sampling values are smaller than the voltage set value within a preset time or the current sampling values are smaller than the current set value within a sampling time period, determining that the voltage loop or the current loop is in an open loop state.

Further, the processor, when executing the computer readable instructions, performs the following steps:

and selecting a time value from t ≧ 1/fg as a critical time value, wherein fg is the loop bandwidth.

And determining a sampling time period according to the critical time value.

Further, the wave-generating control value is expressed by a voltage value or a current value.

Further, the processor, when executing the computer readable instructions, performs the following steps: and when the loop in the open-loop state is a voltage loop, assigning the wave-sending control value of the current beat output represented by the voltage value to the open-loop output value of the current beat.

And when the loop in the open-loop state is a current loop, assigning the wave-sending control value of the current beat output represented by the current value to the open-loop output value of the current beat.

Further, the open-loop output value is obtained based on a difference value, which is an absolute value difference value between the open-loop sampling value and the open-loop given value.

Further, the open-loop output value is calculated by loop compensation through a PI loop compensator, and is obtained from the original open-loop output value after amplitude limiting, wherein the original open-loop output value Piout = Piout1+ k3 Err-k4 Err1, where Piout1 is the open-loop output value of the previous beat, k3 is a first loop calculation coefficient, k4 is a second loop calculation coefficient, Err is a difference value, and Err1 is the difference value of the previous beat.

Further, the closed-loop control circuit comprises a double-loop competition loop and an inner-loop and outer-loop nested loop.

In the embodiment of the application, firstly, a loop in an open-loop state in a closed-loop control circuit is determined, so that loop compensation calculation can be carried out on the loop in the open-loop state; then, acquiring a wave-emitting control value output by the closed-loop control circuit at the current beat, and assigning the wave-emitting control value output by the current beat to the open-loop output value of the current beat so as to enable the wave-emitting control value output by the current beat to replace the loop compensation effect of the loop in the closed-loop state; and finally, calculating the open-loop output value of the next beat of the loop in the open-loop state by adopting the assigned open-loop output value of the current beat, so that the loop can calculate the obtained open-loop output value of the next beat according to the assigned open-loop output value of the current beat in the open-loop state, the compensation effect of the closed-loop is achieved, the take-over time delay of the voltage loop and the current loop of the battery power supply during switching is reduced, and the overshoot problem of the voltage loop and the current loop during switching is avoided.

Furthermore, in the embodiment of the present application, by using the phenomenon that the loop in the open-loop state may have integral saturation, and comparing the voltage sampling value/current sampling value with the voltage given value/current given value corresponding thereto within a preset time existing within the sampling time, the loop in which the voltage sampling value is less than the voltage given value or the current sampling value is less than the current given value within the sampling time period can be determined as the open-loop state.

Furthermore, in the embodiment of the application, a time value can be selected from t ≧ 1/fg as a critical time value, and an interval range from 0 time to the critical time value is taken as a sampling time period from 0 time. Therefore, normal loop compensation calculation of the closed-loop control circuit can be guaranteed, and the closed-loop control circuit can stably operate. The data reliability of the sampled output voltage value or output current value is high, and after the situation that the voltage loop sampling values are smaller than the voltage set value or the current loop sampling values are smaller than the current set value within a preset time exists in the sampling time period is determined, the voltage loop or the current loop can be accurately determined to be in an open loop state.

Further, when the wave-sending control value is assigned to the open-loop output value of the current beat, the assignment of the wave-sending control value can be completed in a voltage value or current value representing mode according to the actual condition that the loop is a voltage loop or a current loop. Therefore, the wave-sending control value can be adjusted and converted in advance, the same expression mode as the original open-loop output value is kept after the value is assigned to the currently-shot open-loop output value, and loop compensation calculation can be rapidly completed on the loop in the open-loop state.

Furthermore, the wave-sending control value is assigned to the open-loop output value of the current beat, the open-loop sampling value is influenced, and correspondingly, the difference value obtained based on the open-loop sampling value is updated along with the beat number, so that when the loop in the open-loop state utilizes the wave-sending control value to realize loop compensation calculation, the data accuracy of the parameters during the compensation calculation can be ensured.

Furthermore, the PI loop compensator can well complete loop compensation calculation, so that the open loop output value is closer to the open loop given value after the loop compensation calculation.

The present application further provides a computer readable storage medium having stored thereon computer readable instructions which, when executed by a processor, implement the steps of a method of suppressing output voltage or output current overshoot as described in the embodiments.

It will be apparent to those skilled in the art that, for convenience and brevity of description, only the above-mentioned division of the functional units and modules is illustrated, and in practical applications, the above-mentioned function distribution may be performed by different functional units and modules according to needs, that is, the internal structure of the apparatus is divided into different functional units or modules, so as to perform all or part of the functions described above.

The above embodiments are only used to illustrate the technical solutions of the present application, and not to limit the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not substantially depart from the spirit and scope of the embodiments of the present application and are intended to be included within the scope of the present application.