阅读说明：本技术 一种抑制电池加热噪声的电机控制方法和电动汽车 (Motor control method for suppressing battery heating noise and electric automobile ) 是由 赵慧超 李岩 潘忠亮 董力嘉 刘亚川 于 2021-08-26 设计创作，主要内容包括：本发明实施例公开了一种抑制电池加热噪声的电机控制方法和电动汽车,其中,电机控制方法包括：在电机输出转矩的模式下,转矩-电流指令计算模块将转矩指令值转换为d轴电流指令及q轴电流指令；在电池加热模式下,加热指令生成模块产生d轴电压加热指令和d轴电流加热指令中的至少一种,d轴电压加热指令和所述d轴电流加热指令均包括幅值和频率变化的波形指令；电机驱动模块根据d轴电流指令及q轴电流指令驱动电机输出设定的转矩,或根据d轴电压加热指令和d轴电流加热指令中的至少一种驱动电机,对动力电池进行充放电形式的加热。本发明实施例能够对动力电池进行均匀加热,提升整车充电速度和效率,并显著削弱电池加热过程中产生的噪声。(The embodiment of the invention discloses a motor control method for inhibiting battery heating noise and an electric automobile, wherein the motor control method comprises the following steps: in a mode that the motor outputs torque, the torque-current instruction calculation module converts a torque instruction value into a d-axis current instruction and a q-axis current instruction; in a battery heating mode, a heating instruction generating module generates at least one of a d-axis voltage heating instruction and a d-axis current heating instruction, wherein the d-axis voltage heating instruction and the d-axis current heating instruction both comprise amplitude and frequency variation waveform instructions; the motor driving module drives the motor to output a set torque according to the d-axis current instruction and the q-axis current instruction, or drives the motor according to at least one of the d-axis voltage heating instruction and the d-axis current heating instruction, so as to heat the power battery in a charging and discharging mode. The embodiment of the invention can uniformly heat the power battery, improve the charging speed and efficiency of the whole vehicle and obviously weaken the noise generated in the battery heating process.)

1. A motor control method for suppressing battery heating noise is characterized in that the method is executed by a motor controller, the motor controller comprises a control module and a motor driving module, the control module comprises a torque-current instruction calculation module and a heating instruction generation module, and the motor driving module is connected with a power battery and a motor;

the method comprises the following steps:

under the mode that the motor outputs torque, the torque-current instruction calculation module converts a torque instruction value into a d-axis current instruction and a q-axis current instruction;

in a battery heating mode, the heating instruction generation module generates at least one of a d-axis voltage heating instruction and a d-axis current heating instruction, wherein the d-axis voltage heating instruction and the d-axis current heating instruction both comprise waveform instructions with amplitude and frequency changes;

the motor driving module drives a motor to output a set torque according to a d-axis current instruction and a q-axis current instruction, or drives the motor according to at least one of a d-axis voltage heating instruction and a d-axis current heating instruction, so as to heat a power battery in a charging and discharging mode.

2. The method of claim 1, wherein the motor drive module drives the motor according to at least one of the d-axis voltage heating command and the d-axis current heating command, comprising:

and the motor driving module outputs a driving signal to the motor according to at least one of the d-axis voltage heating instruction and the d-axis current heating instruction to control the motor not to rotate.

3. The method of claim 1, further comprising:

the control module is used for starting the battery heating mode when the battery is in a low-temperature state and the charging gun of the whole vehicle is recognized to be inserted or a user remote charging appointment request is received.

4. The method of claim 1, wherein in the battery heating mode, the q-axis current command and the q-axis voltage command are zero.

5. The electric automobile is characterized by comprising a motor controller, a motor and a power battery, wherein the motor controller comprises a control module and a motor driving module, the control module comprises a torque-current instruction calculation module and a heating instruction generation module, and the motor driving module is connected with the power battery and the motor;

the torque-current instruction calculation module is used for converting a torque instruction value into a d-axis current instruction and a q-axis current instruction in a mode of outputting torque by the motor;

the heating instruction generating module is used for generating at least one of a d-axis voltage heating instruction and a d-axis current heating instruction in a battery heating mode, wherein the d-axis voltage heating instruction and the d-axis current heating instruction both comprise waveform instructions with amplitude and frequency changes;

the motor driving module is used for driving a motor to output a set torque according to a d-axis current instruction and a q-axis current instruction, or driving the motor according to at least one of the d-axis voltage heating instruction and the d-axis current heating instruction to heat a power battery in a charging and discharging mode.

6. The electric vehicle according to claim 5, wherein the heating instruction generation module includes: a d-axis current heating instruction generation module and/or a d-axis voltage heating instruction generation module;

the d-axis current heating instruction generating module is used for generating a d-axis current heating instruction with amplitude and frequency changes;

and the d-axis voltage heating instruction generation module is used for generating d-axis voltage heating instructions with amplitude and frequency changes.

7. The electric automobile of claim 6, characterized in that the d-axis current heating command generation module comprises a first random amplitude command generation module, a first random frequency command generation module, and a current waveform generation module;

the first random amplitude instruction generating module is used for generating a set waveform amplitude instruction;

the first random frequency instruction generating module is used for generating a set waveform frequency instruction;

the current waveform generation module is used for outputting a d-axis current waveform according to the set waveform amplitude instruction and the set waveform frequency instruction.

8. The electric vehicle of claim 7, wherein the first random amplitude command generating module is configured to output a set waveform amplitude command by using a random number generating function, a random number lookup table, or a set amplitude;

the first random frequency instruction generating module is used for outputting a set waveform frequency instruction by using a random number generating function, a random number lookup table or a set frequency.

9. The electric vehicle according to claim 6, wherein the d-axis voltage heating command generation module comprises a second random amplitude command generation module, a second random frequency command generation module, and a voltage waveform generation module;

the second random amplitude instruction generating module is used for generating a set waveform amplitude instruction;

the second random frequency instruction generating module is used for generating a set waveform frequency instruction;

and the voltage waveform generation module is used for outputting a d-axis voltage waveform according to the set waveform amplitude instruction and the set waveform frequency instruction.

10. The electric vehicle of claim 5, wherein the motor controller further comprises:

the reverse transformation module is used for transforming the three-phase current of the motor from a static coordinate system to a rotating coordinate system to obtain a d-axis current value and a q-axis current value;

the PI control module is used for receiving the difference value between the value of the d-axis current instruction and the d-axis current value and the difference value between the value of the q-axis current instruction and the q-axis current value and outputting a d-axis voltage instruction and a q-axis voltage instruction; or receiving the difference value between the value of the d-axis current heating command and the d-axis current value, setting the difference value between the value of the q-axis current command and the q-axis current value as zero, and outputting a d-axis voltage command and a q-axis voltage command;

the forward conversion module is used for converting the d-axis voltage command into an Alfa-axis voltage command and converting the q-axis voltage command into a Beta-axis voltage command;

and the SVPWM module is used for calculating and outputting a PWM duty ratio instruction based on the Alfa axis voltage instruction and the Beta axis voltage instruction, and controlling the power device of the inverter to be switched on and switched off so as to drive the motor.

Technical Field

The embodiment of the invention relates to the technical field of electric automobiles, in particular to a motor control method for inhibiting battery heating noise and an electric automobile.

Background

As an important composition form of future automobiles, electric and hybrid electric automobiles generate less pollution emission and have higher fuel economy, so that people and various social fields pay attention to the electric and hybrid electric automobiles.

The main power source of electric and hybrid vehicles is the power battery, and the energy of the battery needs to be supplemented by charging. When the ambient temperature is low, the battery cannot be immediately charged at a high power due to the limitation of the characteristics of the battery itself. Therefore, under the low-temperature working condition, the preheating of the battery needs to be completed, and the high-power charging is carried out when the temperature of the battery reaches the proper temperature. At present, the heating mode of the battery system is mainly two, namely, internal heating and external heating. The internal heating mode is to directly heat the inside of the battery through battery resistance or chemical reaction inside the battery, such as high-frequency and low-frequency alternating current heating, battery internal discharge heating, and the like; the external heating means is a means for heating the battery from the outside by generating heat from an external heating unit, such as hot air heating, liquid heating, phase change material heating, heating film heating, and car heater (PTC) heating.

In the heating process, the conventional heating mode can form radial reciprocating acting force on the motor end of the whole vehicle system, and great heating noise is generated.

Disclosure of Invention

The embodiment of the invention provides a motor control method for inhibiting battery heating noise and an electric automobile, so that a power battery is uniformly heated on the premise of not increasing the manufacturing cost of the automobile, the charging speed and efficiency of the whole automobile are improved, and the noise generated in the battery heating process is obviously weakened.

In a first aspect, an embodiment of the present invention provides a motor control method for suppressing battery heating noise, where the method is performed by a motor controller, where the motor controller includes a control module and a motor driving module, the control module includes a torque-current instruction calculation module and a heating instruction generation module, and the motor driving module is connected to a power battery and a motor;

the method comprises the following steps:

under the mode that the motor outputs torque, the torque-current instruction calculation module converts a torque instruction value into a d-axis current instruction and a q-axis current instruction;

in a battery heating mode, the heating instruction generation module generates at least one of a d-axis voltage heating instruction and a d-axis current heating instruction, wherein the d-axis voltage heating instruction and the d-axis current heating instruction both comprise waveform instructions with amplitude and frequency changes;

the motor driving module drives a motor to output a set torque according to a d-axis current instruction and a q-axis current instruction, or drives the motor according to at least one of a d-axis voltage heating instruction and a d-axis current heating instruction, so as to heat a power battery in a charging and discharging mode.

In a second aspect, an embodiment of the present invention further provides an electric vehicle, including a motor controller, a motor, and a power battery, where the motor controller includes a control module and a motor driving module, the control module includes a torque-current instruction calculation module and a heating instruction generation module, and the motor driving module is connected to the power battery and the motor;

the torque-current instruction calculation module is used for converting a torque instruction value into a d-axis current instruction and a q-axis current instruction in a mode of outputting torque by the motor;

the heating instruction generating module is used for generating at least one of a d-axis voltage heating instruction and a d-axis current heating instruction in a battery heating mode, wherein the d-axis voltage heating instruction and the d-axis current heating instruction both comprise waveform instructions with amplitude and frequency changes;

the motor driving module is used for driving a motor to output a set torque according to a d-axis current instruction and a q-axis current instruction, or driving the motor according to at least one of the d-axis voltage heating instruction and the d-axis current heating instruction to heat a power battery in a charging and discharging mode.

According to the technical scheme provided by the embodiment of the invention, based on the existing power system of the whole vehicle, a torque instruction value is converted into a d-axis current instruction and a q-axis current instruction by setting a torque-current instruction calculation module under a mode that a motor outputs torque; under the battery heating mode, the heating instruction generating module is arranged to generate the waveform instruction with the amplitude and the frequency changing, the motor driving module drives the motor according to the waveform instruction with the amplitude and the frequency changing, and the heating means of the charging and discharging mode is carried out on the power battery.

Drawings

Fig. 1 is a flowchart of a motor control method for suppressing battery heating noise according to an embodiment of the present invention;

fig. 2 is a flowchart of a motor control method for suppressing battery heating noise according to a second embodiment of the present invention;

FIG. 3 is a schematic structural diagram of a power system of an electric vehicle according to a third embodiment of the present invention;

fig. 4 is a schematic structural diagram of a heating instruction generating module of an electric vehicle according to a fourth embodiment of the present invention;

fig. 5 is a schematic internal structural diagram of a first random amplitude instruction generating module according to a fourth embodiment of the present invention;

fig. 6 is a schematic diagram of an internal structure of a first random frequency command generating module according to a fourth embodiment of the present invention;

fig. 7 is a schematic structural diagram of another heating instruction generating module of an electric vehicle according to a fourth embodiment of the present invention;

fig. 8 is a schematic structural diagram of a d-axis voltage heating instruction generating module of an electric vehicle according to a fifth embodiment of the present invention;

fig. 9 is a schematic structural diagram of a q-axis voltage heating instruction generating module of an electric vehicle according to a fifth embodiment of the present invention;

FIG. 10 is a schematic structural diagram of a power system of an electric vehicle according to a sixth embodiment of the present invention;

FIG. 11 is a functional block diagram of a powertrain of an electric vehicle according to a sixth embodiment of the present invention;

FIG. 12 is a schematic diagram of a position of a rotor of an electric vehicle in a parking condition without entering a battery heating mode according to a sixth embodiment of the present invention;

fig. 13 is a schematic diagram of a position of a motor rotor when an electric vehicle enters a battery heating mode under a certain parking condition according to a sixth embodiment of the present invention.

Detailed Description

The embodiments of the present invention will be described in further detail with reference to the drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of and not restrictive on the broad invention. It should be further noted that, for convenience of description, only some structures, not all structures, relating to the embodiments of the present invention are shown in the drawings.

Example one

Fig. 1 is a flowchart of a method for controlling a motor to suppress battery heating noise according to an embodiment of the present invention, where the embodiment is applicable to a power battery heating scenario of any device having a motor controller, and the method may be, but is not limited to be, executed by an electric vehicle as an execution subject in the embodiment of the present invention, and the execution subject may be implemented in a software and/or hardware manner. The method is executed by a motor controller, the motor controller comprises a control module and a motor driving module, the control module comprises a torque-current instruction calculation module and a heating instruction generation module, and the motor driving module is connected with a power battery and a motor. As shown in fig. 1, the method specifically includes the following steps:

in step 110, in the mode of the motor outputting the torque, the torque-current instruction calculation module converts the torque instruction value into a d-axis current instruction and a q-axis current instruction.

The power battery may be any rechargeable battery, but the embodiment of the present invention is not limited thereto, and may be, for example, a lithium battery, or may be a nickel-metal hydride battery, or may be a sodium-sulfur battery, or may be a lead-acid battery. The packaging form of the power battery can be a battery cell, or can be a battery module, or can be a battery pack.

The motor controller may be a dc motor controller or may be an ac motor controller. The driving method of the motor controller may be any one, which is not limited in this embodiment of the present invention, and for example, the driving method may be Direct Torque Control (DTC).

The connection link between the power battery and the motor driving module can be an electric link, and the connection link between the motor and the motor driving module can also be an electric link.

The torque-current command calculation module is used for converting a torque command value into a d-axis current command and a q-axis current command.

The torque command value is used to be converted into a d-axis current command and a q-axis current command as a conversion target of the torque-current command calculation module. The signal type of the torque command value may be a digital signal, and the numerical system of the torque command value may be a binary system, which is not limited in this embodiment of the present invention. The transmission manner of the torque command value may be wired transmission, or may be wireless transmission.

The signal types of the d-axis current command and the q-axis current command may be analog signals, which is not limited in this embodiment of the present invention. The transmission mode of the d-axis current command and the q-axis current command may be wired transmission or may be wireless transmission.

And 120, in the battery heating mode, generating at least one of a d-axis voltage heating instruction and a d-axis current heating instruction by using a heating instruction generating module, wherein the d-axis voltage heating instruction and the d-axis current heating instruction both comprise waveform instructions with amplitude and frequency changes.

The heating instruction generation module is used for generating a d-axis voltage heating instruction and/or a d-axis current heating instruction.

The signal types of the d-axis voltage heating command and the d-axis current heating command may be analog signals, which is not limited in this embodiment of the present invention. The transmission manner of the d-axis voltage heating command and the d-axis current heating command may be wired transmission, or may be wireless transmission.

The amplitude and the frequency change rule of the waveform command with the amplitude and the frequency change can be any change rule on the premise of ensuring the safe, normal and stable work of the whole vehicle system, and the embodiment of the invention does not limit the change rule.

And step 130, the motor driving module drives the motor to output a set torque according to the d-axis current instruction and the q-axis current instruction, or drives the motor according to at least one of the d-axis voltage heating instruction and the d-axis current heating instruction, so as to heat the power battery in a charging and discharging mode.

The type of the Motor may be a Permanent Magnet Synchronous Motor (PMSM), an alternating current Asynchronous Motor (ACMC), a Brushless direct current Motor (BLDC), or an Excitation Motor (EEM).

As the output result of the torque-current instruction calculation module, the d-axis current instruction and the q-axis current instruction are used for providing instruction reference for the motor driving module to drive the motor to output the set torque.

The set torque may be set by the operator in advance or on a case-by-case basis, or may be initially set by the system.

In another embodiment, the torque-current command calculation module converts the torque command value into a d-axis current command and a q-axis current command, optionally in a mode in which the motor outputs torque. In the battery heating mode, the heating command generation module generates at least one of a q-axis voltage heating command and a q-axis current heating command, each of which includes a waveform command of varying amplitude and frequency. The motor driving module drives the motor to output a set torque according to the d-axis current instruction and the q-axis current instruction, or drives the motor according to at least one of the q-axis voltage heating instruction and the q-axis current heating instruction, so as to heat the power battery in a charging and discharging mode.

According to the technical scheme of the embodiment, based on the existing power system of the whole vehicle, in a mode that a motor outputs torque, a torque instruction value is converted into a d-axis current instruction and a q-axis current instruction through a torque-current instruction calculation module; under the battery heating mode, the heating instruction generating module is arranged to generate the waveform instruction with the amplitude and the frequency changing, the motor driving module drives the motor according to the waveform instruction with the amplitude and the frequency changing, and the heating means of the charging and discharging mode is carried out on the power battery.

Example two

Fig. 2 is a flowchart of a motor control method for suppressing battery heating noise according to a second embodiment of the present invention, which is added based on the first embodiment of the present invention. As shown in fig. 2, optionally, the motor control method for suppressing the battery heating noise further includes:

and step 140, the control module starts a battery heating mode when the control module identifies that a charging gun is inserted into the whole vehicle or receives a remote charging appointment request of a user when the battery is in a low-temperature state.

The specific threshold setting of the low temperature state may be initial parameter setting of the entire vehicle system, or may be user-defined setting.

Optionally, in the battery heating mode, the q-axis current command and the q-axis voltage command are zero.

Optionally, the motor driving module drives the motor according to at least one of the d-axis voltage heating instruction and the d-axis current heating instruction, and the motor driving module outputs a driving signal to the motor according to at least one of the d-axis voltage heating instruction and the d-axis current heating instruction to control the motor not to rotate.

The driving signal is used as an output signal of the motor driving module and an input control signal of the motor and is used for controlling the motor not to rotate. The signal type of the driving signal may be a digital signal, and the number system of the driving signal may be a binary system, which is not limited in this embodiment of the present invention. The transmission mode of the driving signal may be wired transmission or may be wireless transmission.

In another embodiment, the torque-current command calculation module converts the torque command value into a d-axis current command and a q-axis current command, optionally in a mode in which the motor outputs torque.

The control module is used for starting a battery heating mode when the battery is in a low-temperature state and the whole vehicle is identified to have a charging gun inserted or a user remote charging appointment request is received.

In the battery heating mode, the heating command generation module generates at least one of a q-axis voltage heating command and a q-axis current heating command, each of which includes a waveform command of varying amplitude and frequency.

The motor driving module drives the motor to output a set torque according to the d-axis current instruction and the q-axis current instruction, or drives the motor according to at least one of the q-axis voltage heating instruction and the q-axis current heating instruction, so as to heat the power battery in a charging and discharging mode.

In the battery heating mode, the d-axis current command and the d-axis voltage command are zero.

The motor driving module drives the motor according to at least one of the q-axis voltage heating instruction and the q-axis current heating instruction, and the motor driving module outputs a driving signal to the motor according to at least one of the q-axis voltage heating instruction and the q-axis current heating instruction to control the motor not to rotate.

The technical scheme of this embodiment, based on the existing driving system of whole car, when discerning that the whole car has the rifle of charging to insert or receive the long-range reservation request of charging of user under the battery is in the low temperature state through setting up control module, the means of opening the battery heating mode has solved current battery heating mode and can only carry out the battery heating under the condition that the user is in the car to there are the problem that hardware cost is high and heating time is long, realized under the prerequisite that does not increase car manufacturing cost, the user can make a appointment the battery heating in advance, the effect of whole car low temperature charging time has been reduced.

In addition, according to the technical scheme of the embodiment, in the mode that the motor outputs the torque, the torque instruction value is converted into a d-axis current instruction and a q-axis current instruction through the setting of the torque-current instruction calculation module; under the battery heating mode, the heating instruction generating module is arranged to generate the waveform instruction with the amplitude and the frequency changing, the motor driving module drives the motor according to the waveform instruction with the amplitude and the frequency changing, and the heating means of the charging and discharging mode is carried out on the power battery.

EXAMPLE III

Fig. 3 is a schematic structural diagram of a power system of an electric vehicle according to a third embodiment of the present invention. As shown in fig. 3, the powertrain system of the electric vehicle includes a motor controller 210, a motor 220, and a power battery 230. The motor controller 210 includes a control module 211 and a motor drive module 212. The control module 211 includes a torque-current command calculation module 211a and a heating command generation module 211 b. The motor driving module 212 connects the power battery 230 and the motor 220.

The torque-current command calculation module 211a is configured to convert the torque command value into a d-axis current command and a q-axis current command in a mode in which the motor 220 outputs torque.

The heating instruction generating module 211b is configured to generate at least one of a d-axis voltage heating instruction and a d-axis current heating instruction in the battery heating mode, where the d-axis voltage heating instruction and the d-axis current heating instruction each include a waveform instruction with an amplitude and a frequency that vary.

The motor driving module 212 is configured to drive the motor 220 to output a set torque according to the d-axis current command and the q-axis current command, or drive the motor 220 according to at least one of the d-axis voltage heating command and the d-axis current heating command, so as to heat the power battery 230 in a charging and discharging manner.

The d-axis voltage heating command may be any form of alternating voltage command including amplitude and frequency changes, which is not limited in this embodiment of the present invention, and may be, for example, an alternating voltage command including amplitude and frequency changes in the form of a square wave, an alternating voltage command including amplitude and frequency changes in the form of a sine wave, an alternating voltage command including amplitude and frequency changes in the form of a triangular wave, an alternating voltage command including amplitude and frequency changes in the form of a trapezoidal wave, or an alternating voltage command including amplitude and frequency changes in the form of a stepped wave.

The d-axis current heating command may be any form of alternating current command including amplitude and frequency changes, and the embodiment of the present invention is not limited thereto, and for example, may be an alternating current command including amplitude and frequency changes in the form of a square wave, or an alternating current command including amplitude and frequency changes in the form of a sine wave, or an alternating current command including amplitude and frequency changes in the form of a triangular wave, or an alternating current command including amplitude and frequency changes in the form of a trapezoidal wave, or an alternating current command including amplitude and frequency changes in the form of a stepped wave.

In another embodiment, the torque-current command calculation module 211a is optionally configured to convert the torque command value into a d-axis current command and a q-axis current command in a mode in which the motor 220 outputs torque.

The heating command generation module 211b may be configured to generate at least one of a q-axis voltage heating command and a q-axis current heating command in the battery heating mode, each of the q-axis voltage heating command and the q-axis current heating command including a waveform command of varying amplitude and frequency.

The motor driving module 212 may be configured to drive the motor 220 to output a set torque according to the d-axis current command and the q-axis current command, or drive the motor 220 according to at least one of the q-axis voltage heating command and the q-axis current heating command, so as to heat the power battery 230 in a charging and discharging manner.

According to the technical scheme of the embodiment, based on the existing power system of the whole vehicle, a torque instruction value is converted into a d-axis current instruction and a q-axis current instruction by arranging a torque-current instruction calculation module under a mode that a motor outputs torque. In a battery heating mode, a heating instruction generating module is arranged to generate a d-axis voltage heating instruction and/or a d-axis current heating instruction with amplitude and frequency changes, and a motor driving module drives a motor according to the d-axis voltage heating instruction and/or the d-axis current heating instruction to heat a power battery in a charging and discharging mode. The defects of large heating noise, poor heating uniformity, high hardware cost and low heating efficiency of the conventional battery heating mode are overcome, the uniform heating of the power battery based on the conventional power system of the whole vehicle is realized on the premise of not increasing the manufacturing cost of the vehicle, the low-temperature charging time of the whole vehicle is reduced, and the effect of obviously weakening the heating noise of the battery is realized.

Example four

Fig. 4 is a schematic structural diagram of a heating instruction generating module of an electric vehicle according to a fourth embodiment of the present invention, which is detailed based on a third embodiment of the present invention. As shown in fig. 4, optionally, the heating instruction generating module 211b includes a d-axis current heating instruction generating module 211b1 and/or a d-axis voltage heating instruction generating module 211b 2.

The d-axis current heating command generating module 211b1 is configured to generate a d-axis current heating command with varying amplitude and frequency.

The d-axis voltage heating command generating module 211b2 is configured to generate a d-axis voltage heating command with amplitude and frequency variation.

Optionally, the d-axis current heating command generating module 211b1 includes a first random magnitude command generating module 211b11, a first random frequency command generating module 211b12, and a current waveform generating module 211b 13.

The first random amplitude command generating module 211b11 is used to generate a set waveform amplitude command.

The first random frequency command generating module 211b12 is used to generate a set waveform frequency command.

The current waveform generation module 211b13 is configured to output a d-axis current waveform according to a set waveform amplitude command and a set waveform frequency command.

The internal structure of the first random magnitude instruction generating module 211b11 may be as shown in fig. 5, and the internal structure of the first random frequency instruction generating module 211b12 may be as shown in fig. 6. The waveform amplitude command and the waveform frequency command may be used to provide a command reference for the current waveform generation module 211b13 to output a d-axis current waveform. The waveform amplitude command and the waveform frequency command may be adaptively set by a user according to actual needs, which is not limited in the embodiment of the present invention.

The d-axis current waveforms may correspond one-to-one to the d-axis current heating commands. For example, when the d-axis current heating command is an alternating current command including amplitude and frequency variations in the form of a square wave, the d-axis current waveform is an alternating square wave including amplitude and frequency variations; when the d-axis current heating command is an alternating current command including amplitude and frequency variations in the form of a sine wave, the d-axis current waveform is an alternating sine wave including amplitude and frequency variations; when the d-axis current heating command is an alternating current command including amplitude and frequency variations in the form of a triangular wave, the d-axis current waveform is an alternating triangular wave including amplitude and frequency variations; when the d-axis current heating command is an alternating current command including amplitude and frequency variations in the form of a trapezoidal wave, the d-axis current waveform is an alternating trapezoidal wave including amplitude and frequency variations; when the d-axis current heating command is an alternating current command including amplitude and frequency variations in the form of a step wave, the d-axis current waveform is an alternating step wave including amplitude and frequency variations.

Optionally, the first random amplitude instruction generating module 211b11 is configured to implement the output of the set waveform amplitude instruction by using a random number generating function, a random number lookup table, or a set amplitude.

The first random frequency command generating module 211b12 is used for outputting the set waveform frequency command by using a random number generating function, a random number lookup table, or a set frequency.

The random number generating function and the random number lookup table are used to provide a basis for the first random amplitude command generating module 211b11 to output the waveform amplitude command, and the first random frequency command generating module 211b12 to output the waveform frequency command.

The signal type of the waveform amplitude command and the waveform frequency command may be digital signals, and the number system of the two waveform commands may be binary, which is not limited in the embodiment of the present invention. The transmission mode of the two waveform commands can be wired transmission or wireless transmission.

In another embodiment, fig. 7 is a schematic structural diagram of another heating instruction generating module of an electric vehicle according to an embodiment of the present invention. Referring to fig. 7, optionally, the heating instruction generation module 211b may include a q-axis current heating instruction generation module 211b3 and/or a q-axis voltage heating instruction generation module 211b 4. The q-axis current heating command generation module 211b3 is configured to generate a q-axis current heating command that varies in magnitude and frequency. The q-axis voltage heating command generation module 211b4 is configured to generate a q-axis voltage heating command with amplitude and frequency variations.

The q-axis current heating command generation module 211b3 may include a third random magnitude command generation module 211b31, a third random frequency command generation module 211b32, and a second current waveform generation module 211b 33. The third random amplitude command generating module 211b31 is configured to generate a set waveform amplitude command. The third random frequency command generating module 211b32 is used to generate a set waveform frequency command. The second current waveform generation module 211b33 is configured to output a q-axis current waveform according to a set waveform amplitude command and a set waveform frequency command.

The q-axis current waveform may correspond one-to-one to the q-axis current heating command. For example, when the q-axis current heating command is an alternating current command including amplitude and frequency variations in the form of a square wave, the q-axis current waveform is an alternating square wave including amplitude and frequency variations; when the q-axis current heating command is an alternating current command including amplitude and frequency variations in the form of a sine wave, the q-axis current waveform is an alternating sine wave including amplitude and frequency variations; when the q-axis current heating command is an alternating current command including amplitude and frequency variations in the form of a triangular wave, the q-axis current waveform is an alternating triangular wave including amplitude and frequency variations; when the q-axis current heating command is an alternating current command including amplitude and frequency variations in the form of a trapezoidal wave, the q-axis current waveform is an alternating trapezoidal wave including amplitude and frequency variations; when the q-axis current heating command is an alternating current command including amplitude and frequency variations in the form of a step wave, the q-axis current waveform is an alternating step wave including amplitude and frequency variations.

Optionally, the third random amplitude instruction generating module 211b31 is configured to implement the output of the set waveform amplitude instruction by using a random number generating function, a random number lookup table, or a set amplitude.

The third random frequency command generating module 211b32 is used for outputting the set waveform frequency command by using a random number generating function, a random number lookup table, or a set frequency.

In yet another embodiment, the heating command generating module 211b of the electric vehicle may further include a d-axis current heating command generating module 211b1, and/or a d-axis voltage heating command generating module 211b2, and/or a q-axis current heating command generating module 211b3, and/or a q-axis voltage heating command generating module 211b4, which have similar technical principles and similar implementation effects and are not repeated herein.

According to the technical scheme of the embodiment, the d-axis current heating instruction generating module comprising the first random amplitude instruction generating module, the first random frequency instruction generating module and the current waveform generating module is arranged, so that the d-axis current heating instruction with the variable amplitude and frequency can be output. The motor is driven based on the d-axis current heating instruction, the power battery is heated in a charging and discharging mode, the problem of high heating noise of an existing battery heating mode is solved, the power battery is heated based on an existing power system of the whole vehicle on the premise that the manufacturing cost of the vehicle is not increased, and the effect of obviously weakening the heating noise of the battery is achieved.

EXAMPLE five

Fig. 8 is a schematic structural diagram of a d-axis voltage heating instruction generating module of an electric vehicle according to a fifth embodiment of the present invention, which is refined based on the fourth embodiment of the present invention. As shown in fig. 8, optionally, the d-axis voltage heating command generating module 211b2 includes a second random magnitude command generating module 211b21, a second random frequency command generating module 211b22, and a voltage waveform generating module 211b 23.

The second random amplitude command generating module 211b21 is used to generate a set waveform amplitude command.

The second random frequency command generating module 211b22 is used to generate a set waveform frequency command.

The voltage waveform generation module 211b23 is configured to output a d-axis voltage waveform according to a set waveform amplitude command and a set waveform frequency command.

The second random amplitude instruction generating module 211b21 may be specifically configured to implement the output of the set waveform amplitude instruction by using a random number generating function, a random number lookup table, or a set amplitude.

The second random frequency command generating module 211b22 may be specifically configured to implement the output of the set waveform frequency command by using a random number generating function, a random number lookup table, or a set frequency.

The waveform amplitude command and the waveform frequency command may be used to provide a command reference for the voltage waveform generation module 211b23 to output a d-axis voltage waveform.

The d-axis voltage waveform may correspond one-to-one to the d-axis voltage heating command. For example, when the d-axis voltage heating command is an alternating voltage command comprising amplitude and frequency variations in the form of a square wave, the d-axis voltage waveform is an alternating square wave comprising amplitude and frequency variations; when the d-axis voltage heating command is an alternating voltage command including amplitude and frequency variations in the form of a sine wave, the d-axis voltage waveform is an alternating sine wave including amplitude and frequency variations; when the d-axis voltage heating command is an alternating voltage command including amplitude and frequency variations in the form of a triangular wave, the d-axis voltage waveform is an alternating triangular wave including amplitude and frequency variations; when the d-axis voltage heating command is an alternating voltage command including amplitude and frequency variations in the form of a trapezoidal wave, the d-axis voltage waveform is an alternating trapezoidal wave including amplitude and frequency variations; when the d-axis voltage heating command is an alternating voltage command including amplitude and frequency variations in the form of a step wave, the d-axis voltage waveform is an alternating step wave including amplitude and frequency variations.

In another embodiment, fig. 9 is a schematic structural diagram of a q-axis voltage heating instruction generating module of an electric vehicle according to an embodiment of the present invention, and this embodiment is refined based on the schematic structural diagram of the heating instruction generating module of another electric vehicle shown in fig. 7.

Referring to fig. 9, the q-axis voltage heating command generating module 211b4 may optionally include a fourth random magnitude command generating module 211b41, a fourth random frequency command generating module 211b42, and a second voltage waveform generating module 211b 43. The fourth random amplitude command generating module 211b41 is configured to generate a set waveform amplitude command. The fourth random frequency command generating module 211b42 is used to generate a set waveform frequency command. The second voltage waveform generation module 211b43 is configured to output a q-axis voltage waveform according to a set waveform amplitude command and a set waveform frequency command.

The fourth random amplitude instruction generating module 211b41 may be specifically configured to implement the output of the set waveform amplitude instruction by using a random number generating function, a random number lookup table, or a set amplitude.

The fourth random frequency command generating module 211b42 may be specifically configured to implement the output of the set waveform frequency command by using a random number generating function, a random number lookup table, or a set frequency.

The waveform amplitude command and the waveform frequency command may be used to provide a command reference for the second voltage waveform generation module 211b43 to output the q-axis voltage waveform.

The q-axis voltage waveform may correspond one-to-one to the q-axis voltage heating command. For example, when the q-axis voltage heating command is an alternating voltage command comprising amplitude and frequency variations in the form of a square wave, the q-axis voltage waveform is an alternating square wave comprising amplitude and frequency variations; when the q-axis voltage heating command is an alternating voltage command including amplitude and frequency variations in the form of a sine wave, the q-axis voltage waveform is an alternating sine wave including amplitude and frequency variations; when the q-axis voltage heating command is an alternating voltage command including amplitude and frequency variations in the form of a triangular wave, the q-axis voltage waveform is an alternating triangular wave including amplitude and frequency variations; when the q-axis voltage heating command is an alternating voltage command including amplitude and frequency variations in the form of a trapezoidal wave, the q-axis voltage waveform is an alternating trapezoidal wave including amplitude and frequency variations; when the q-axis voltage heating command is an alternating voltage command including amplitude and frequency variations in the form of a step wave, the q-axis voltage waveform is an alternating step wave including amplitude and frequency variations.

In addition, the value selection of the waveform amplitude command and the waveform frequency command can be determined according to the speed requirement of battery heating and the upper limit of the hardware capacity of the motor and the motor controller. The larger the amplitude of the excitation waveform, the faster the heating rate of the power battery, but the requirement that the current value of the motor controller does not exceed the maximum allowable current value still needs to be met. The lower the frequency of the excitation waveform, the faster the power cell heats up, but the safety characteristics of the power cell also need to be met.

According to the technical scheme of the embodiment, the d-axis voltage heating instruction generating module comprising the second random amplitude instruction generating module, the second random frequency instruction generating module and the voltage waveform generating module is arranged, so that the d-axis voltage heating instruction with the amplitude and frequency changing can be output. The motor is driven based on the d-axis voltage heating instruction, the power battery is heated in a charging and discharging mode, the problem of high heating noise of an existing battery heating mode is solved, the power battery is heated based on an existing power system of the whole vehicle on the premise that the manufacturing cost of the vehicle is not increased, and the effect of obviously weakening the heating noise of the battery is achieved.

EXAMPLE six

Fig. 10 is a schematic structural diagram of a power system of an electric vehicle according to a sixth embodiment of the present invention, which is added based on the third embodiment of the present invention. As shown in fig. 10, the motor controller 210 further includes an inverse transform module 213, a Proportional Integral (PI) control module 214, a forward transform module 215, and a Space Vector Pulse Width Modulation (SVPWM) module 216.

The inverse transformation module 213 is configured to transform the three-phase current of the motor from the stationary coordinate system to the rotating coordinate system to obtain a d-axis current value and a q-axis current value.

The PI control module 214 is configured to receive a difference between a value of the d-axis current command and a d-axis current value and a difference between a value of the q-axis current command and a q-axis current value, and output a d-axis voltage command and a q-axis voltage command; or receiving the difference between the value of the d-axis current heating command and the d-axis current value, setting the difference between the value of the q-axis current command and the q-axis current value to be zero, and outputting a d-axis voltage command and a q-axis voltage command.

The forward conversion module 215 is configured to convert the d-axis voltage command into an Alfa-axis voltage command and convert the q-axis voltage command into a Beta-axis voltage command.

The SVPWM module 216 is configured to calculate and output a Pulse Width Modulation (PWM) duty command based on the Alfa axis voltage command and the Beta axis voltage command, and control a power device of the inverter to be turned on and off to drive the motor 220.

The signal types of the d-axis current value and the q-axis current value may be digital signals, and the number system of the d-axis current value and the q-axis current value may be binary, which is not limited in this embodiment of the present invention. The transmission manner of the d-axis current value and the q-axis current value may be wired transmission, or may be wireless transmission.

The value of the d-axis current command is used for subtraction from the d-axis current value. The difference between the value of the d-axis current command and the d-axis current value is calculated by a subtractor or a comparator, which is not limited in the embodiment of the present invention. The signal type of the value of the d-axis current command may be a digital signal, and the numerical system of the value of the d-axis current command may be a binary system, which is not limited in this embodiment of the present invention. The transmission manner of the value of the d-axis current command may be wired transmission, or may be wireless transmission.

The value of the q-axis current command is used for subtraction from the q-axis current value. The difference between the q-axis current command value and the q-axis current value is calculated by a subtractor or a comparator, which is not limited in the embodiment of the present invention. The signal type of the value of the q-axis current command may be a digital signal, and the numerical system of the value of the q-axis current command may be a binary system, which is not limited in this embodiment of the present invention. The transmission manner of the value of the q-axis current command may be wired transmission, or may be wireless transmission.

The value of the d-axis current heating command is used for subtraction from the d-axis current value. The difference between the d-axis current heating command value and the d-axis current value is calculated by a subtractor or a comparator, which is not limited in the embodiment of the present invention. The signal type of the value of the d-axis current heating instruction may be a digital signal, and the numerical system of the value of the d-axis current heating instruction may be a binary system, which is not limited in this embodiment of the present invention. The transmission manner of the value of the d-axis current heating command may be wired transmission, or may be wireless transmission.

The value of the q-axis current heating command is used for subtraction from the q-axis current value. The difference between the q-axis current heating command value and the q-axis current value is calculated by a subtractor or a comparator, which is not limited in the embodiment of the present invention. The signal type of the value of the q-axis current heating instruction may be a digital signal, and the numerical system of the value of the q-axis current heating instruction may be a binary system, which is not limited in this embodiment of the present invention. The transmission manner of the value of the q-axis current heating command may be wired transmission, or may be wireless transmission.

The d-axis voltage command and the q-axis voltage command, which are conversion targets of the forward conversion module 215, may be used to be converted into the Alfa-axis voltage command and the Beta-axis voltage command by the forward conversion module 215, respectively. The signal types of the Alfa axis voltage command and the Beta axis voltage command may be analog signals, and the transmission modes of the Alfa axis voltage command and the Beta axis voltage command may be wired transmission or wireless transmission.

The Alfa axis voltage command and the Beta axis voltage command are used to provide command references for the SVPWM module 216 to calculate the output PWM duty cycle command. The PWM duty command may be a digital signal, and the number system of the PWM duty command may be a binary system, which is not limited in this embodiment of the present invention. The transmission mode of the PWM duty command may be wired transmission or may be wireless transmission.

The power device of the inverter may be any type or category of Insulated Gate Bipolar Transistor (IGBT) or Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET), which is not limited in this embodiment of the present invention.

In another embodiment, the PI control module 214 may be configured to receive a difference between a value of the d-axis current heating command and a d-axis current value, and a difference between a value of the q-axis current command and a q-axis current value, which are set to zero, and output a d-axis voltage command and a q-axis voltage command.

In another embodiment, fig. 11 is a functional block diagram of a power system of an electric vehicle according to an embodiment of the present invention. Referring to fig. 11, on the basis of the above technical solution, optionally, the electric vehicle further includes a torque command receiving module 310, a motor position sensor 320, a motor position information transmitting module 330, and an inverter 340. The motor position sensor 320 may be a resolver, or may be an incremental encoder, or may be any sensor that can sense motor rotor position information. The embodiment of the present invention is described by taking the three-phase permanent magnet synchronous motor 220a as an example, but the embodiment of the present invention is not limited thereto.

In the power system of the electric vehicle, after the motor position sensor 320 detects the motor rotor position θ and the motor speed information ω of the three-phase permanent magnet synchronous motor 220a, the motor position information transmission module 320 transmits the motor rotor position θ and the motor speed information ω to the forward conversion module 215 and the reverse conversion module 213. Three-phase current I of reverse conversion module 213 based on three-phase permanent magnet synchronous motor 220a_{u_value}、I_{v_value}And I_{w_value}Completing the coordinate system transformation and obtaining the d-axis current value I_{d_value}And q-axis current value I_{q_value}. In the motor torque output mode, torque command receiving module 310 receives a torque command Te sent by VCU_cmdAnd sent to the torque-current command calculation module 211 a. Torque-current command calculation module 211a outputs torque command Te_cmdValue conversion to d-axis current command i_{d_cmd}And q-axis current command i_{q_cmd}. d-axis current command i_{d_cmd}And q-axis current command i_{q_cmd}Respectively corresponding to d-axis current value I_{d_value}And q-axis current value I_{q_value}After the difference is made, the difference is input to the PI control module 214. PI control module 214 calculates and outputs d-axis voltage command u_dAnd q-axis voltage command u_q. d-axis voltage command u_dAnd q-axis voltage command u_qAfter coordinate transformation operation of the forward transformation module 215, the d-axis voltage command u is converted_dConverted into Alfa axis voltage command u_αQ-axis voltage command u_qConverted into Beta axis voltage command u_β. Alfa axis voltage command u_αAnd Beta axis voltage command u_βAfter the input to the SVPWM module 216, 6 PWM duty ratio commands are output through calculation of the SVPWM module 216, and the 6 PWM duty ratio commands control the on and off of the 6 power devices UT, VT, WT, UB, VB and WB of the inverter 340, thereby controlling the three-phase permanent magnet synchronous motor 220a to output a specified torque.

Based on the above-described motor control scheme, the d-axis current heating command generation module 211b1 may give the d-axis current heating command i in the form of an alternating waveform command including amplitude and frequency variations_dAnd giving the q-axis current heating command 0, or may give the q-axis current heating command i in the form of an alternating waveform command comprising amplitude and frequency variations_qGiving a d-axis current heating command as 0; the d-axis voltage heating command generation module 211b2 may give the d-axis voltage heating command u in the form of an alternating waveform command including amplitude and frequency variations_dAnd giving the q-axis voltage heating command 0, or the q-axis voltage heating command u may be given in the form of an alternating waveform command comprising amplitude and frequency variations_qAnd giving the d-axis voltage heating command 0.

The d-axis current heating command generation module 211b1 gives the d-axis current heating command i in the form of an alternating waveform command including amplitude and frequency variations_dThe reasons and advantages are as follows. If the d-axis current heating command generation module 211b1 gives the d-axis current heating command in the form of an alternating waveform command, the alternating d-axis current heating command can ensure that the three-phase permanent magnet synchronous motor 220a does not rotateSo as to meet the requirements of parking heating. However, the alternating d-axis current heating command may cause the three-phase pmsm 220a to reciprocate in the radial direction, so that a regular single-frequency noise may be generated during the battery heating process, and the noise may cause a certain trouble to a user in the vehicle. Therefore, the motor control method provided by the embodiment of the invention can enable the noise frequency distribution of the electric drive system in the battery heating process to tend to disperse by utilizing the random waveform amplitude instruction and the random waveform frequency instruction, thereby remarkably reducing the noise in the vehicle.

The d-axis voltage heating instruction generation module 211b2 gives the d-axis voltage heating instruction u in the form of an alternating waveform instruction including amplitude and frequency variations_dThe reasons and advantages are similar, and the description is omitted.

Based on the motor control scheme, alternating charge-discharge current can be formed at the bus end, and the alternating charge-discharge current can realize the heating function of the power battery under the low-temperature working condition. In addition, the heating current or voltage command of the d-axis or the q-axis is given as 0 in order to ensure that the three-phase permanent magnet synchronous motor 220a does not continuously output torque during the heating of the power battery. Therefore, the scheme of the embodiment also meets the working condition that the whole vehicle is in a parking state when the low-temperature battery is heated and charged.

In another embodiment, fig. 12 is a schematic diagram of a position of a motor rotor of an electric vehicle that does not enter a battery heating mode under a certain parking condition according to an embodiment of the present invention, and fig. 13 is a schematic diagram of a position of a motor rotor of an electric vehicle that enters a battery heating mode under a certain parking condition according to an embodiment of the present invention.

Referring to fig. 12 and 13, on the basis of the above technical solutions, optionally, since the position where the motor rotor stays when not entering the battery heating mode is closest to the basic vectors U5 and U1, after entering the battery heating mode, the rotor moves to the position where the basic vectors U5 and U1 are located. According to the basic principle of the SVPWM algorithm, the switching devices of the inverter are switched between two switching modes, i.e., U5(110) and U1(001), and finally a charging and discharging current is formed at the bus, and the charging and discharging current heats the battery.

Optionally, when the rotor position of the vehicle in the parking condition is located at another position, after entering the battery heating mode, the rotor position of the motor may be moved to the position of 6 basic vectors nearby, and the battery is heated according to the state of the switching device represented by the basic vectors.

The technical scheme of this embodiment, give the alternating d axle current heating instruction including amplitude and frequency variation through setting up d axle current heating instruction generation module, d axle voltage heating instruction generation module gives the alternating d axle voltage heating instruction including amplitude and frequency variation, and then form the charge-discharge current of alternation at system bus end, the means of heating is carried out for power battery under the low temperature operating mode to the charge-discharge current based on the alternation, it is big to have filled current battery heating mode heating noise, the heating homogeneity is poor, the hardware is with high costs, the low defect of heating efficiency, realized under the prerequisite that does not increase car manufacturing cost, power battery carries out the uniform heating based on current driving system of whole car, reduce whole car low temperature charging time, show the effect that weakens battery heating noise.

It is to be noted that the foregoing is only illustrative of the preferred embodiments of the present invention and the technical principles employed. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, but is capable of various obvious changes, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, although the present invention has been described in greater detail by the above embodiments, the present invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the spirit of the present invention, and the scope of the present invention is determined by the scope of the appended claims.