阅读说明：本技术 一种电机控制器逆变频率的自动调节方法及相关设备 (Automatic adjusting method of inversion frequency of motor controller and related equipment ) 是由 朱相军 徐刚 许心一 饶健 李文灿 于 2020-12-15 设计创作，主要内容包括：本发明公开一种电机控制器逆变频率的自动调节方法及相关设备,包括：测量电机运行时的三相电流；根据所述三相电流和当前电角度下的目标电流计算电流谐波有效值；根据预设电流谐波目标值与所述电流谐波有效值的差值以及电机转速与逆变频率的预设上限曲线和预设下限曲线,调节电机控制器的所述逆变频率。能够实现逆变频率与电机转速的自适应动态调节。(The invention discloses an automatic adjusting method of inversion frequency of a motor controller and related equipment, comprising the following steps: measuring three-phase current when the motor runs; calculating a current harmonic effective value according to the three-phase current and the target current under the current electrical angle; and adjusting the inversion frequency of the motor controller according to the difference value between the preset current harmonic target value and the current harmonic effective value and the preset upper limit curve and the preset lower limit curve of the motor rotating speed and the inversion frequency. The self-adaptive dynamic regulation of the inversion frequency and the motor rotating speed can be realized.)

1. A method for automatically adjusting the inverter frequency of a motor controller is characterized by comprising the following steps:

measuring three-phase current when the motor runs;

calculating a current harmonic effective value according to the three-phase current and the target current under the current electrical angle;

and adjusting the inversion frequency of the motor controller according to the difference value between the preset current harmonic target value and the current harmonic effective value and the preset upper limit curve and the preset lower limit curve of the motor rotating speed and the inversion frequency.

2. The method as claimed in claim 1, wherein the step of measuring three-phase current of the motor during operation comprises:

measuring three-phase current of the motor during operation according to a measurement period;

the step of calculating the current harmonic effective value according to the three-phase current and the target current under the current electrical angle comprises the following steps:

performing Clark conversion on the three-phase current to obtain a D-axis current and a Q-axis current;

and calculating a current harmonic effective value according to the D-axis current, the Q-axis current and the target current under the current electrical angle.

3. The method of claim 2, wherein the step of calculating an effective value of a current harmonic from the D-axis current, the Q-axis current, and a target current at a present electrical angle comprises:

calculating the current harmonic effective value I according to the following formula_hrms：

Wherein, I_drefFor a D-axis target current at the present electrical angle, I_qrefTarget current of Q axis at present electrical angle, I_dfdIs the D-axis current, I_qfdIs the Q-axis current, t₀And delta t is the measurement starting time of the three-phase current, and is the measurement period of the three-phase current.

4. The method of claim 1, wherein the step of adjusting the inverter frequency of the motor controller according to the difference between the preset current harmonic target value and the current harmonic effective value and the preset upper limit curve and the preset lower limit curve of the motor speed and the inverter frequency comprises:

subtracting the current harmonic effective value from a preset current harmonic target value to obtain an effective difference value;

when the effective difference value is larger than 0, the inversion frequency of a motor controller is adjusted downwards, and according to a preset lower limit curve of the motor rotating speed and the inversion frequency, the adjusted inversion frequency is larger than or equal to the lower limit value of the inversion frequency corresponding to the current motor rotating speed;

when the effective difference value is smaller than 0, the inverter frequency of a motor controller is adjusted upwards, and according to a preset upper limit curve of the motor rotating speed and the inverter frequency, the adjusted inverter frequency is smaller than or equal to an inverter frequency upper limit value corresponding to the current motor rotating speed;

when the effective difference value is equal to 0, the inversion frequency is not adjusted.

5. The method of claim 1, comprising:

and carrying out low-pass filtering processing on the regulated inversion frequency.

6. The method for automatically adjusting the inverter frequency of the motor controller according to claim 1, wherein a maximum value of a preset upper limit curve of the motor rotation speed and the inverter frequency is a maximum safe inverter frequency of the motor controller;

and the minimum value of the preset lower limit curve of the motor rotating speed and the inversion frequency is the lowest stable operation inversion frequency of the motor controller.

7. The method of claim 1, wherein the period of the three-phase current is greater than 10 times the pulse period.

8. An automatic regulating apparatus of a motor controller inversion frequency, comprising:

the three-phase current measuring module is used for measuring three-phase current when the motor runs;

the current harmonic effective value calculating module is used for calculating a current harmonic effective value according to the three-phase current and the target current at the current electrical angle;

and the inversion frequency adjusting module is used for adjusting the inversion frequency of the motor controller according to the difference value between the preset current harmonic target value and the current harmonic effective value and the preset upper limit curve and the preset lower limit curve of the motor rotating speed and the inversion frequency.

9. An electronic device, comprising: memory, processor and computer program stored in the memory and executable on the processor, characterized in that the processor is adapted to implement the steps of the method for automatic adjustment of inverter frequency of a motor controller according to any of claims 1-7 when executing the computer program stored in the memory.

10. A computer-readable storage medium, on which a computer program is stored which, when being executed by a processor, carries out the steps of the method for automatic adjustment of an inverter frequency of a motor controller according to any one of claims 1 to 7.

Technical Field

The invention relates to the technical field of motor control, in particular to an automatic adjusting method of inverter frequency of a motor controller and related equipment.

Background

The permanent magnet synchronous motor electric drive system is used as a main flow scheme of new energy and widely applied to vehicle types such as pure electric or hybrid electric and the like. In an existing motor controller, a fixed corresponding relationship between a motor rotation speed and an inversion frequency is formed by performing linear table lookup and interpolation on the inversion frequency (pwm frequency) through the motor rotation speed.

However, the fixed correspondence relationship between the motor rotation speed and the inverter frequency does not take into account the factors of variables such as voltage, torque and temperature, and when the inverter frequency is higher, although the output current harmonic of the motor controller and the torque ripple can be reduced, the loss of the motor controller is increased, and the efficiency of the motor controller is reduced. For example, for a high voltage platform, a motor electric drive system has a wider voltage working range, if the inversion frequency is not flexibly adjusted in combination with a voltage factor, when the inversion frequency is determined according to a fixed corresponding relation between the motor rotating speed and the inversion frequency, a high voltage region corresponds to a high motor rotating speed, the high motor rotating speed corresponds to a high inversion frequency, and the high inversion frequency corresponds to high efficiency, but the loss of a motor controller is increased; the low-pressure region corresponds to a low motor speed, the low motor speed corresponds to a low inversion frequency, and the low inversion frequency corresponds to a low efficiency.

Disclosure of Invention

The invention provides an automatic adjusting method of an inversion frequency of a motor controller and related equipment, which can realize self-adaptive dynamic adjustment of the inversion frequency and the motor rotating speed.

In a first aspect, a method for automatically adjusting an inverter frequency of a motor controller includes:

measuring three-phase current when the motor runs;

calculating a current harmonic effective value according to the three-phase current and the target current under the current electrical angle;

and adjusting the inversion frequency of the motor controller according to the difference value between the preset current harmonic target value and the current harmonic effective value and the preset upper limit curve and the preset lower limit curve of the motor rotating speed and the inversion frequency.

Optionally, the step of measuring the three-phase current when the motor operates includes:

measuring three-phase current of the motor during operation according to a measurement period;

the step of calculating the current harmonic effective value according to the three-phase current and the target current under the current electrical angle comprises the following steps:

performing Clark conversion on the three-phase current to obtain a D-axis current and a Q-axis current;

and calculating a current harmonic effective value according to the D-axis current, the Q-axis current and the target current under the current electrical angle.

Optionally, the step of calculating a current harmonic effective value according to the D-axis current, the Q-axis current, and a target current at a current electrical angle includes:

calculating the current harmonic effective value I according to the following formula_hrms：

Wherein, I_drefFor a D-axis target current at the present electrical angle, I_qrefTarget current of Q axis at present electrical angle, I_dfdIs the D-axis current, I_qfdIs the Q-axis current, t₀And delta t is the measurement starting time of the three-phase current, and is the measurement period of the three-phase current.

Optionally, the step of adjusting the inverter frequency of the motor controller according to the difference between the preset current harmonic target value and the current harmonic effective value and the preset upper limit curve and the preset lower limit curve of the motor speed and the inverter frequency includes:

subtracting the current harmonic effective value from a preset current harmonic target value to obtain an effective difference value;

when the effective difference value is larger than 0, the inversion frequency of a motor controller is adjusted downwards, and according to a preset lower limit curve of the motor rotating speed and the inversion frequency, the adjusted inversion frequency is larger than or equal to the lower limit value of the inversion frequency corresponding to the current motor rotating speed;

when the effective difference value is smaller than 0, the inverter frequency of a motor controller is adjusted upwards, and according to a preset upper limit curve of the motor rotating speed and the inverter frequency, the adjusted inverter frequency is smaller than or equal to an inverter frequency upper limit value corresponding to the current motor rotating speed;

when the effective difference value is equal to 0, the inversion frequency is not adjusted.

Optionally, the method further comprises:

and carrying out low-pass filtering processing on the regulated inversion frequency.

Optionally, the maximum value of the preset upper limit curve of the motor rotation speed and the inverter frequency is the maximum safe inverter frequency of the motor controller;

and the minimum value of the preset lower limit curve of the motor rotating speed and the inversion frequency is the lowest stable operation inversion frequency of the motor controller.

Optionally, the measurement period of the three-phase current is greater than 10 times the pulse period.

In a second aspect, an apparatus for automatically adjusting an inverter frequency of a motor controller includes:

the three-phase current measuring module is used for measuring three-phase current when the motor runs;

the current harmonic effective value calculating module is used for calculating a current harmonic effective value according to the three-phase current and the target current at the current electrical angle;

and the inversion frequency adjusting module is used for adjusting the inversion frequency of the motor controller according to the difference value between the preset current harmonic target value and the current harmonic effective value and the preset upper limit curve and the preset lower limit curve of the motor rotating speed and the inversion frequency.

In a third aspect, an electronic device includes: the automatic adjusting method for the inverter frequency of the motor controller is characterized by comprising a storage, a processor and a computer program which is stored in the storage and can run on the processor, wherein the processor is used for realizing the steps of any one of the automatic adjusting methods for the inverter frequency of the motor controller when executing the computer program stored in the storage.

In a fourth aspect, a computer-readable storage medium has stored thereon a computer program which, when executed by a processor, implements the steps of any of the above-described methods for automatically adjusting an inverter frequency of a motor controller.

The application provides an automatic adjustment method and relevant equipment of motor controller contravariant frequency, adopt circulating automatic adjustment mode, according to the three-phase current of predetermined measuring cycle measurement motor, carry out current harmonic analysis calculation to the three-phase current that records, obtain current harmonic effective value, the size of preset current harmonic target value and current harmonic effective value is compared, judge whether current motor controller's contravariant frequency is suitable, if improper, need adjust current motor controller's contravariant frequency, the control range can not exceed motor speed and the preset lower limit curve and the preset line curve that go up of contravariant frequency. The regulation of the inversion frequency can be adaptive to factors such as the rotating speed of the motor, the rotating torque of the motor, the running voltage of the motor, the running temperature of the motor and the like, the existing mode of adjusting the inversion frequency according to the fixed corresponding relation between the rotating speed of the motor and the inversion frequency of the motor controller is improved, and the motor can keep higher running efficiency on the premise that the motor controller is in safe and stable running.

Drawings

Fig. 1 is a schematic flow chart of a method for automatically adjusting an inverter frequency of a motor controller according to an embodiment of the present application;

FIG. 2 is a schematic flow chart of a method for calculating an effective value of a current harmonic according to a three-phase current and a target current at a current electrical angle according to an embodiment of the present disclosure;

fig. 3 is a schematic flowchart of a method for adjusting an inverter frequency of a motor controller according to a difference between a preset current harmonic target value and a current harmonic effective value, and a preset upper limit curve and a preset lower limit curve of a motor speed and an inverter frequency, according to an embodiment of the present disclosure;

fig. 4 is a schematic diagram of a preset lower limit curve and a preset upper line curve of the motor rotation speed and the inverter frequency provided in the embodiment of the present application;

fig. 5 is a schematic structural block diagram of an automatic adjusting device for inverter frequency of a motor controller according to an embodiment of the present application;

fig. 6 is a schematic structural block diagram of an electronic device provided in an embodiment of the present application;

fig. 7 is a schematic structural block diagram of a computer-readable storage medium according to an embodiment of the present application.

Detailed Description

In order to better understand the technical solutions provided by the embodiments of the present specification, the technical solutions of the embodiments of the present specification are described in detail below with reference to the drawings and specific embodiments, and it should be understood that the specific features in the embodiments and examples of the present specification are detailed descriptions of the technical solutions of the embodiments of the present specification, and are not limitations on the technical solutions of the embodiments of the present specification, and the technical features in the embodiments and examples of the present specification may be combined with each other without conflict.

In this document, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element. The term "two or more" includes the case of two or more.

In the existing motor controller, linear table look-up interpolation is usually performed on the inversion frequency through the rotating speed of the motor to form a fixed corresponding relation between the rotating speed of the motor and the inversion frequency. However, the fixed correspondence relationship between the motor rotation speed and the inverter frequency does not take into account the factors of variables such as voltage, torque and temperature, and when the inverter frequency is higher, although the output current harmonic of the motor controller and the torque ripple can be reduced, the loss of the motor controller is increased, and the efficiency of the motor controller is reduced. For example, for a high voltage platform, a motor electric drive system has a wider voltage working range, if the inversion frequency is not flexibly adjusted in combination with a voltage factor, when the inversion frequency is determined according to a fixed corresponding relation between the motor rotating speed and the inversion frequency, a high voltage region corresponds to a high motor rotating speed, the high motor rotating speed corresponds to a high inversion frequency, and the high inversion frequency corresponds to high efficiency, but the loss of a motor controller is increased; the low-pressure region corresponds to a low motor speed, the low motor speed corresponds to a low inversion frequency, and the low inversion frequency corresponds to a low efficiency.

In view of this, the present application provides an automatic adjusting method and related device for inverter frequency of a motor controller, which dynamically adjusts the inverter frequency through online harmonic analysis of a motor driving system. The application provides a motor controller inverter frequency's automatic regulating method and relevant equipment are applied to new energy automobile usually, can be pure electric vehicles also can be mixed moving vehicle, and this application does not do not specifically limit.

In a possible implementation manner, fig. 1 is a schematic flow chart of an automatic adjusting method of an inverter frequency of a motor controller according to an embodiment of the present application. As shown in fig. 1, the method for automatically adjusting an inverter frequency of a motor controller according to this embodiment includes:

s1: and measuring three-phase current when the motor runs.

In one possible implementation, step S1 may include:

and measuring the three-phase current of the motor in operation according to the measurement period. The motor usually adopts three-phase electricity power supply, and measurement cycle can set for according to actual demand, and this application does not do not specifically limit.

S2: and calculating a current harmonic effective value according to the measured three-phase current and the target current under the current electrical angle.

Fig. 2 is a schematic flowchart of a method for calculating an effective current harmonic value according to a three-phase current and a target current at a current electrical angle according to an embodiment of the present application. As shown in fig. 2, in another possible embodiment, step S2 may include the following steps:

s21: and performing Clark conversion on the three-phase current to obtain D-axis current and Q-axis current. Because the three-phase current of the asynchronous motor has current values of three phases, the analysis and the processing of the current are complex in the process of carrying out harmonic analysis on the three-phase current, so that the complex three-phase coordinate system of the three-phase current can be directly converted into a two-phase coordinate system without carrying out the analysis of harmonic components in order to reduce the calculated amount and the data amount. When the magnitudes and the rotating speeds of the rotating magnetomotive forces generated by the three-phase winding and the two-phase winding are equal, the two-phase winding is considered to be equivalent to the three-phase winding, and the two-phase winding can be represented by D-axis current and Q-axis current (or represented by alpha coordinate axis and beta coordinate axis currents), which is the basis of Clark transformation.

S22: and calculating the current harmonic effective value according to the D-axis current, the Q-axis current and the target current in the current electrical angle.

The current harmonic effective value I can be calculated as follows_hrms：

Wherein, I_drefFor a D-axis target current at the present electrical angle, I_qrefTarget current of Q axis at present electrical angle, I_dfdIs a D-axis current, I_qfdIs Q-axis current, t₀The method includes the steps that the measurement starting time of three-phase current is set, delta t is the measurement period of the three-phase current, the measurement period of the delta t three-phase current is far larger than the pulse period of a motor controller, the measurement period of the delta t three-phase current can be larger than 10 times of the pulse period, and the method is not limited specifically. D-axis target current I at present electrical angle_drefAnd a target current I of the Q axis at the present electrical angle_qrefAre both two-dimensional components of a preset target value, it is easily understood that the present electrical angle is a sine angle. The target value and the measured value of the current are subjected to the correlation operation of difference and integral, and the obtained current harmonic effective value can be used as a motorThe current value fed back by the circuits in the row.

Execution continues with step S3: and adjusting the inversion frequency of the motor controller according to the difference value between the preset current harmonic target value and the current harmonic effective value and the preset upper limit curve and the preset lower limit curve of the motor rotating speed and the inversion frequency.

Fig. 3 is a schematic flowchart of a method for adjusting an inverter frequency of a motor controller according to a difference between a preset current harmonic target value and a current harmonic effective value, and a preset upper limit curve and a preset lower limit curve of a motor speed and an inverter frequency according to an embodiment of the present application. As shown in fig. 3, in another possible implementation, step S3 may include:

s31: and subtracting the current harmonic effective value from the preset current harmonic target value to obtain an effective difference value. The preset current harmonic target value is a current harmonic target value preset according to analysis of long-term motor operation data and combination of empirical values; the preset current harmonic target value can be used as a standard for dynamic regulation of inversion frequency by a motor controller in the motor operation process. The effective difference value obtained by subtracting the current harmonic effective value from the preset current harmonic target value can reflect whether the current inverter frequency of the motor operation is proper or not.

Execution continues with step S32: and when the effective difference value is larger than 0, the inversion frequency of the motor controller is adjusted downwards, and according to a preset lower limit curve of the motor rotating speed and the inversion frequency, the adjusted inversion frequency is larger than or equal to the lower limit value of the inversion frequency corresponding to the current motor rotating speed. When the effective difference value is greater than 0, it is described that the current harmonic effective value representing the actual operating current condition is lower than the preset current harmonic target value, further described that the inverter frequency of the motor controller is higher, the higher inverter frequency may cause damage to the motor controller, at this time, the inverter frequency of the motor controller needs to be adjusted downward to avoid damage to the motor controller, and according to a preset lower limit curve of the motor rotation speed and the inverter frequency, the adjusted inverter frequency is greater than or equal to the inverter frequency lower limit corresponding to the current motor rotation speed, so that the motor can maintain higher operating efficiency on the premise that the motor controller is in safe and stable operation.

The maximum value and the minimum value of a preset lower limit curve and a preset upper line curve of the motor rotating speed and the inverter frequency are required to be set according to the safe and stable operation of the motor controller, and the minimum value of the preset lower limit curve of the motor rotating speed and the inverter frequency is the lowest stable operation inverter frequency of the motor controller; the maximum value of the preset upper limit curve of the motor rotating speed and the inversion frequency is the maximum safe inversion frequency of the motor controller. Fig. 4 is a schematic diagram of a preset lower limit curve and a preset upper line curve of the motor rotation speed and the inverter frequency provided in the embodiment of the present application. As shown in fig. 4, the maximum value and the minimum value of the preset lower limit curve L2 and the preset upper line curve L1 of the normal motor speed and the inverter frequency may be the same, for example, when V0 is 100 revolutions, the minimum value p0 of the inverter frequency is 2.5 KHz; when V1 is 8000-.

Execution continues with step S33: and when the effective difference value is less than 0, the inversion frequency of the motor controller is adjusted upwards, and the adjusted inversion frequency is less than or equal to the upper limit value of the inversion frequency corresponding to the current motor rotating speed according to the preset upper limit curve of the motor rotating speed and the inversion frequency. When the effective difference value is less than 0, it is described that the current harmonic effective value representing the actual operating current situation is higher than the preset current harmonic target value, further described that the inverter frequency of the motor controller is relatively low, the relatively low inverter frequency may cause the motor to be in a state of relatively low operating efficiency, at this time, the inverter frequency of the motor controller needs to be adjusted up to keep the motor in a state of relatively high operating efficiency, and according to a preset upper limit curve of the motor rotation speed and the inverter frequency, the adjusted up inverter frequency is smaller than the lower limit value of the inverter frequency corresponding to the current motor rotation speed, so that the motor can keep relatively high operating efficiency on the premise that the motor controller is in safe and stable operation. No matter the inversion frequency is adjusted up or down, the inversion frequency cannot exceed the numerical range corresponding to the closed graph enclosed by the preset lower limit curve L2 and the preset upper line curve L1 of the motor rotation speed and the inversion frequency shown in fig. 4. The adjusting mode of the step S32 and the step S33 makes the motor rotation speed and the inverter frequency not be in a one-to-one fixed corresponding relationship any more, and in a numerical range corresponding to a closed graph enclosed by a preset lower limit curve L2 and a preset upper line curve L1 of the motor rotation speed and the inverter frequency, one motor rotation speed can correspond to the inverter frequency of a plurality of motor controllers, and the inverter frequency of one motor controller can correspond to a plurality of motor rotation speeds; because the current harmonic effective value representing the actual operation current condition is the current value, the current value can reflect the conditions of voltage, temperature, efficiency and the like in the operation of the motor, and the rotation torque of the motor can be reflected, the adjustment method of the step S32 and the step S33 enables the adjustment of the inverter frequency to be adaptive to the factors of the rotation speed of the motor, the rotation torque of the motor, the operation voltage of the motor, the operation temperature of the motor and the like, improves the existing mode of adjusting the inverter frequency according to the fixed corresponding relation between the rotation speed of the motor and the inverter frequency of the motor controller, and can realize that the motor can keep higher operation efficiency on the premise that the motor controller is in safe and stable operation.

S34: when the effective difference value is equal to 0, the current harmonic effective value representing the actual operation current situation is equivalent to the preset current harmonic target value, and further the inversion frequency of the motor controller is proper and does not need to be adjusted.

S4: and carrying out low-pass filtering processing on the regulated inversion frequency. Because the computing power of the existing computer is strong, the computing speed is fast, the inversion frequency adjusted in step S3 is an unstable fluctuation value, after low-pass filtering, the value of the inversion frequency tends to be stable, the inversion frequency after low-pass filtering is transmitted to the motor to drive the motor to operate, and the motor can keep high operation efficiency on the premise that the motor controller is in safe and stable operation.

The method for automatically adjusting the inverter frequency of the motor controller provided by the embodiment of the application adopts a circulating automatic adjustment mode, measures the three-phase current of the motor according to a preset measurement period, performs current harmonic analysis and calculation on the measured three-phase current to obtain a current harmonic effective value, compares a preset current harmonic target value with the current harmonic effective value to judge whether the inverter frequency of the current motor controller is proper, if not, the inverter frequency of the current motor controller needs to be adjusted, the adjustment range can not exceed a preset lower limit curve and a preset upper line curve of the motor rotating speed and the inverter frequency, and the adjusted inverter frequency is transmitted to the motor to drive the motor to operate after being subjected to low-pass filtering. The regulation of the inversion frequency can be adaptive to factors such as the rotating speed of the motor, the rotating torque of the motor, the running voltage of the motor, the running temperature of the motor and the like, the existing mode of adjusting the inversion frequency according to the fixed corresponding relation between the rotating speed of the motor and the inversion frequency of the motor controller is improved, and the motor can keep higher running efficiency on the premise that the motor controller is in safe and stable running.

Fig. 5 is a schematic structural block diagram of an automatic adjusting device for inverter frequency of a motor controller according to an embodiment of the present application. As shown in fig. 5, an automatic adjusting apparatus for inverter frequency of a motor controller includes:

and the three-phase current measuring module 1 is used for measuring three-phase current when the motor runs.

And the current harmonic effective value calculating module 2 is used for calculating a current harmonic effective value according to the three-phase current and the target current at the current electrical angle.

The current harmonic effective value calculation module 2 includes:

the Clark conversion submodule 21 is used for performing Clark conversion on the three-phase current to obtain a D-axis current and a Q-axis current;

and the calculation submodule 22 is used for calculating the current harmonic effective value according to the D-axis current, the Q-axis current and the target current in the current electrical angle.

The inverter frequency adjusting module 3 includes:

and the inversion frequency adjusting module 3 is used for adjusting the inversion frequency of the motor controller according to the difference value between the preset current harmonic target value and the current harmonic effective value, and the preset upper limit curve and the preset lower limit curve of the motor rotating speed and the inversion frequency.

The inverter frequency adjusting module 3 includes:

and the difference value calculating submodule 31 is configured to subtract the current harmonic effective value from the preset current harmonic target value to obtain an effective difference value.

And the inversion frequency down-regulation module 32 is used for down-regulating the inversion frequency of the motor controller when the effective difference value is greater than 0, and the down-regulated inversion frequency is greater than or equal to the inversion frequency lower limit value corresponding to the current motor rotating speed according to a preset lower limit curve of the motor rotating speed and the inversion frequency.

And the inversion frequency up-regulation sub-module 33 is configured to up-regulate the inversion frequency of the motor controller when the effective difference is smaller than 0, and according to a preset upper limit curve of the motor rotation speed and the inversion frequency, the up-regulated inversion frequency is smaller than or equal to the inversion frequency lower limit value corresponding to the current motor rotation speed.

And an inversion frequency holding sub-module 34 for not adjusting the inversion frequency when the effective difference is equal to 0.

The inverter further comprises a low-pass filtering module 4 for performing low-pass filtering processing on the adjusted inversion frequency.

It will be appreciated that the configuration shown in fig. 5 is merely illustrative and that embodiments of the present disclosure provide apparatus that may include more or fewer components than shown in fig. 5 or that have a different configuration than shown in fig. 5. The components shown in fig. 5 may be implemented in hardware, software, or a combination thereof.

Fig. 6 is a schematic structural block diagram of an electronic device according to an embodiment of the present application. As shown in fig. 6, an electronic device 600 according to an embodiment of the present application includes a memory 610, a processor 620, and a computer program 611 stored in the memory 610 and executable on the processor 620, where the processor 620 executes the computer program 611 to implement the following steps:

measuring three-phase current when the motor runs;

calculating a current harmonic effective value according to the three-phase current and the target current under the current electrical angle;

and adjusting the inversion frequency of the motor controller according to the difference value between the preset current harmonic target value and the current harmonic effective value and the preset upper limit curve and the preset lower limit curve of the motor rotating speed and the inversion frequency.

In particular embodiments, any of the above embodiments may be implemented when the processor 620 executes the computer program 611.

Since the electronic device described in this embodiment is an automatic adjusting device for implementing the inverter frequency of the motor controller in this embodiment, based on the method described in this embodiment, those skilled in the art can understand the specific implementation manner of the electronic device of this embodiment and various variations thereof, so that how to implement the method in this embodiment by the electronic device will not be described in detail herein, and as long as the device used by those skilled in the art to implement the method in this embodiment belongs to the scope of protection of this application.

Fig. 7 is a schematic structural block diagram of a computer-readable storage medium according to an embodiment of the present application. As shown in fig. 7, the present embodiment provides a computer-readable storage medium 700 having a computer program 711 stored thereon, the computer program 711, when executed by a processor, implementing the steps of:

measuring three-phase current when the motor runs;

calculating a current harmonic effective value according to the three-phase current and the target current under the current electrical angle;

and adjusting the inversion frequency of the motor controller according to the difference value between the preset current harmonic target value and the current harmonic effective value and the preset upper limit curve and the preset lower limit curve of the motor rotating speed and the inversion frequency.

In a specific implementation, the computer program 711 may implement any of the embodiments described above when executed by a processor.

The description has been presented with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the description. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

While preferred embodiments of the present specification have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. Therefore, it is intended that the appended claims be interpreted as including preferred embodiments and all changes and modifications that fall within the scope of the specification.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present specification without departing from the spirit and scope of the specification. Thus, if such modifications and variations of the present specification fall within the scope of the claims of the present specification and their equivalents, the specification is intended to include such modifications and variations.