阅读说明：本技术 电机零位的确定方法和装置 (Method and device for determining zero position of motor ) 是由 徐鲁辉 杜智勇 肖恺 于 2018-07-27 设计创作，主要内容包括：本公开涉及一种电机零位的确定方法和装置,该方法包括：根据预设的第一占空比和第一电流值,在对电机通电后,确定在电机的转子到达预设位置时转子的第一角度；控制电机的电流清零；控制电机的转速达到正转时的第一预设转速后在惯性状态下运行第一预设时间,以在第一预设时间完成后获取转子的第二角度；控制电机的转速达到反转时的第二预设转速后在惯性状态下运行第二预设时间,以在第二预设时间完成后获取转子的第三角度；根据第一角度、第二角度和第三角度,确定电机的零位。能够有效地确定电机的零位,并利用实时在线处理,不需要人为修正,操作简便,节约成本。(The present disclosure relates to a method and a device for determining a zero position of a motor, wherein the method comprises the following steps: according to the preset first duty ratio and the first current value, after the motor is electrified, determining a first angle of a rotor when the rotor of the motor reaches a preset position; current zero clearing of the control motor; controlling the rotating speed of the motor to reach a first preset rotating speed in forward rotation and then operating for a first preset time in an inertial state so as to obtain a second angle of the rotor after the first preset time is finished; controlling the rotating speed of the motor to reach a second preset rotating speed during reverse rotation and then operating for a second preset time in an inertial state so as to obtain a third angle of the rotor after the second preset time is finished; and determining the zero position of the motor according to the first angle, the second angle and the third angle. The zero position of the motor can be effectively determined, real-time online processing is utilized, manual correction is not needed, the operation is simple and convenient, and the cost is saved.)

1. A method of determining a zero position of an electric motor, the method comprising:

according to a preset first duty ratio and a first current value, after the motor is electrified, determining a first angle of a rotor when the rotor of the motor reaches a preset position;

controlling the current of the motor to be reset;

controlling the rotating speed of the motor to reach a first preset rotating speed in forward rotation and then operating for a first preset time in an inertial state so as to obtain a second angle of the rotor after the first preset time is finished;

controlling the rotating speed of the motor to reach a second preset rotating speed during reverse rotation and then operating for a second preset time in an inertial state so as to obtain a third angle of the rotor after the second preset time is finished;

and determining a zero position of the motor according to the first angle, the second angle and the third angle.

2. The method of claim 1, wherein determining the first angle of the rotor of the electric machine when the rotor reaches the preset position after the electric machine is energized according to a preset first duty cycle and a first current value comprises:

setting duty ratios of the phases of the motor according to the first duty ratio;

after the duty ratio of each phase is set, electrifying the motor according to the first current value;

when the rotor reaches the preset position, determining the first angle according to the preset position;

and writing the first angle into a control program of the motor.

3. The method of claim 1, wherein said controlling current to zero of said motor comprises:

setting the duty cycle of each phase of the motor to the initial duty cycle;

and controlling the current output of the motor to be zero by utilizing the initial duty ratio.

4. The method of claim 1, wherein the controlling the rotation speed of the motor to reach a first preset rotation speed in the forward rotation and then to operate in the inertia state for a first preset time to obtain a second angle of the rotor after the first preset time is completed comprises:

controlling the rotating speed of the motor in forward rotation to reach the first preset rotating speed by using a first current control instruction;

controlling the motor to operate for the first preset time in an inertial state by using a second current control instruction;

after the first preset time is finished, acquiring a first direct axis voltage and a first quadrature axis voltage of the motor;

determining the second angle according to the first direct axis voltage and the first quadrature axis voltage;

and writing the second angle into a control program of the motor.

5. The method of claim 1, wherein the controlling the rotational speed of the motor to reach a second preset rotational speed at the reverse rotation and then operating in the inertia state for a second preset time to obtain a third angle of the rotor after the second preset time is completed comprises:

controlling the rotating speed of the motor to be reduced to an initial rotating speed value by using a third current control instruction;

clearing the current of the motor by using a fourth current control instruction;

controlling the rotating speed of the motor to reach the second preset rotating speed when the motor rotates reversely by using a fifth current control instruction;

controlling the motor to operate for the second preset time in an inertial state by using a sixth current control instruction;

after the second preset time is finished, acquiring a second direct axis voltage and a second quadrature axis voltage of the motor;

determining the third angle according to the second direct axis voltage and the second quadrature axis voltage;

and writing the third angle into a control program of the motor.

6. The method of claim 1, further comprising:

after the third angle is obtained, a seventh current control instruction is used for controlling the rotating speed of the motor to be reduced to an initial rotating speed value;

and clearing the current of the motor by using an eighth current control command.

7. The method of claim 1, further comprising, prior to said determining a zero position of the motor from the first angle, the second angle, and the third angle:

repeatedly executing the step of controlling the rotation speed of the motor to reach a first preset rotation speed during forward rotation and then operating the motor for a first preset time in an inertia state so as to obtain a second angle of the rotor after the first preset time is finished, and executing the step of controlling the rotation speed of the motor to reach a second preset rotation speed during reverse rotation and then operating the motor for a second preset time in the inertia state so as to obtain a third angle of the rotor after the second preset time is finished at least once so as to obtain at least one group of second angle and third angle again;

determining a zero position of the motor according to the first angle, the second angle, and the third angle includes:

calculating the average value of the obtained multiple groups of second angles and third angles;

and taking the difference value of the first angle and the average value as the zero position of the motor.

8. An apparatus for determining a zero position of an electric motor, the apparatus comprising:

the first angle determining module is used for determining a first angle of a rotor of the motor when the rotor reaches a preset position after the motor is electrified according to a preset first duty ratio and a first current value;

the current zero clearing module is used for controlling the current zero clearing of the motor;

the angle acquisition module is further used for controlling the motor to run for a first preset time in an inertia state after the rotating speed of the motor reaches a first preset rotating speed in forward rotation so as to acquire a second angle of the rotor after the first preset time is finished;

the angle acquisition module is further configured to control the motor to operate for a second preset time in an inertial state after the rotation speed of the motor reaches a second preset rotation speed during reverse rotation, so as to acquire a third angle of the rotor after the second preset time is completed;

and the zero position determining module is used for determining the zero position of the motor according to the first angle, the second angle and the third angle.

9. The apparatus of claim 8, wherein the first angle determining module comprises:

the duty ratio setting submodule is used for setting the duty ratio of each phase of the motor according to the first duty ratio;

the energization submodule is used for energizing the motor according to the first current value after the duty ratio of each phase is set;

the angle determining submodule is used for determining the first angle according to the preset position when the rotor reaches the preset position;

and the angle writing submodule is used for writing the first angle into a control program of the motor.

10. The apparatus of claim 8, wherein the current zero module comprises:

the duty ratio setting submodule is used for setting the duty ratio of each phase of the motor as the initial duty ratio;

and the current zero clearing submodule is used for controlling the current output of the motor to be zero by utilizing the initial duty ratio.

11. The apparatus of claim 8, wherein the angle acquisition module comprises:

the rotating speed control submodule is used for controlling the rotating speed of the motor to reach the first preset rotating speed in the forward rotation process by utilizing a first current control instruction;

the operation control submodule is used for controlling the motor to operate for the first preset time in an inertial state by utilizing a second current control instruction;

the voltage acquisition submodule is used for acquiring a first direct-axis voltage and a first quadrature-axis voltage of the motor after the first preset time is finished;

the angle determining submodule is used for determining the second angle according to the first direct-axis voltage and the first quadrature-axis voltage;

and the angle writing submodule is used for writing the second angle into a control program of the motor.

12. The apparatus of claim 8, wherein the angle acquisition module comprises:

the rotating speed control submodule is also used for controlling the rotating speed of the motor to be reduced to an initial rotating speed value by utilizing a third current control instruction;

the current zero clearing submodule is used for clearing the current of the motor by utilizing a fourth current control instruction;

the rotating speed control submodule is also used for controlling the rotating speed of the motor to reach the second preset rotating speed when the motor rotates reversely by using a fifth current control instruction;

the operation control sub-module is further used for controlling the motor to operate for the second preset time in an inertial state by using a sixth current control instruction;

the voltage obtaining submodule is further used for obtaining a second direct-axis voltage and a second quadrature-axis voltage of the motor after the second preset time is finished;

the angle determining submodule is further configured to determine the third angle according to the second direct-axis voltage and the second quadrature-axis voltage;

and the angle writing submodule is also used for writing the third angle into a control program of the motor.

13. The apparatus of claim 8, further comprising:

the rotating speed control module is used for controlling the rotating speed of the motor to be reduced to an initial rotating speed value by utilizing a seventh current control instruction after the third angle is obtained;

the current zero clearing module is further used for clearing the current of the motor by using an eighth current control instruction.

14. The apparatus of claim 8, further comprising:

the repeated execution module is used for repeatedly executing the step of controlling the rotating speed of the motor to reach a first preset rotating speed during forward rotation and then operating the motor for a first preset time in the inertia state so as to obtain a second angle of the rotor after the first preset time is finished and the step of controlling the rotating speed of the motor to reach a second preset rotating speed during reverse rotation and then operating the motor for a second preset time in the inertia state so as to obtain a third angle of the rotor after the second preset time is finished at least once so as to obtain at least one group of second angle and third angle again;

the zero determination module is configured to:

calculating the average value of the obtained multiple groups of second angles and third angles;

and taking the difference value of the first angle and the average value as the zero position of the motor.

Technical Field

The disclosure relates to the technical field of machinery, in particular to a method and a device for determining a zero position of a motor.

Background

The integration of electric automobile is a definite development direction, and more manufacturers integrate the relevant power spare part of electric drive together and form the electric drive bridge, comprises three key components of motor controller, motor and reduction gear promptly, and motor controller and motor combination form the matching together. The zero position of the motor is a critical factor for controlling synchronous motors, and is a critical point for the orientation of the magnetic field in motor control. There are many test schemes to the zero position of the motor among the prior art, including: the method comprises the following steps of testing zero crossing points of no-load back electromotive force of the motor, comparing motor parameters by presetting a data table, and testing the direct current of the tested motor. However, some of the test schemes can need a whole set of motor test bench, and other test schemes need manual adjustment, so that the dependence on equipment and personnel is strong, large-batch zero position test is not easy to realize, and accurate test of the zero position of the motor system is not facilitated again after the motor parts are replaced.

Disclosure of Invention

The purpose of the present disclosure is to provide a method and an apparatus for determining a zero position of a motor, which can simplify operations and save costs without relying on manual calibration and a complete set of bench test systems.

According to a first aspect of the embodiments of the present disclosure, there is provided a method for determining a zero position of a motor, the method including:

according to a preset first duty ratio and a first current value, after the motor is electrified, determining a first angle of a rotor when the rotor of the motor reaches a preset position;

controlling the current of the motor to be reset;

controlling the rotating speed of the motor to reach a first preset rotating speed in forward rotation and then operating for a first preset time in an inertial state so as to obtain a second angle of the rotor after the first preset time is finished;

controlling the rotating speed of the motor to reach a second preset rotating speed during reverse rotation and then operating for a second preset time in an inertial state so as to obtain a third angle of the rotor after the second preset time is finished;

and determining the zero position of the motor according to the first angle, the second angle and the third angle.

Optionally, the determining, according to a preset first duty cycle and a preset first current value, a first angle of a rotor of the motor when the rotor reaches a preset position after the motor is powered on includes:

setting duty ratios of the phases of the motor according to the first duty ratio;

after the duty ratio of each phase is set, electrifying the motor according to the first current value;

when the rotor reaches the preset position, determining the first angle according to the preset position;

and writing the first angle into a control program of the motor.

Optionally, the current zero clearing for controlling the motor includes:

setting the duty cycle of each phase of the motor to the initial duty cycle;

and controlling the current output of the motor to be zero by utilizing the initial duty ratio.

Optionally, the controlling the rotation speed of the motor to reach a first preset rotation speed during forward rotation and then operate for a first preset time in an inertial state, so as to obtain a second angle of the motor after the first preset time is completed, includes:

controlling the rotating speed of the motor in forward rotation to reach the first preset rotating speed by using a first current control instruction;

controlling the motor to operate for the first preset time in an inertial state by using a second current control instruction;

after the first preset time is finished, acquiring a first direct axis voltage and a first quadrature axis voltage of the motor;

determining the second angle according to the first direct axis voltage and the first quadrature axis voltage;

and writing the second angle into a control program of the motor.

Optionally, the controlling the rotation speed of the motor to reach a second preset rotation speed during the reverse rotation and then operate for a second preset time in the inertia state, so as to obtain a third angle of the rotor after the second preset time is completed, includes:

controlling the rotating speed of the motor to be reduced to an initial rotating speed value by using a third current control instruction;

clearing the current of the motor by using a fourth current control instruction;

controlling the rotating speed of the motor to reach the second preset rotating speed when the motor rotates reversely by using a fifth current control instruction;

controlling the motor to operate for the second preset time in an inertial state by using a sixth current control instruction;

after the second preset time is finished, acquiring a second direct axis voltage and a second quadrature axis voltage of the motor;

determining the third angle according to the second direct axis voltage and the second quadrature axis voltage;

and writing the third angle into a control program of the motor.

Optionally, the method further includes:

after the third angle is obtained, a seventh current control instruction is used for controlling the rotating speed of the motor to be reduced to an initial rotating speed value;

and clearing the current of the motor by using an eighth current control command.

Optionally, before the determining the zero position of the motor according to the first angle, the second angle, and the third angle, the method further includes:

repeatedly executing the step of controlling the rotation speed of the motor to reach a first preset rotation speed during forward rotation and then operating the motor for a first preset time in an inertia state so as to obtain a second angle of the rotor after the first preset time is finished, and executing the step of controlling the rotation speed of the motor to reach a second preset rotation speed during reverse rotation and then operating the motor for a second preset time in the inertia state so as to obtain a third angle of the rotor after the second preset time is finished at least once so as to obtain at least one group of second angle and third angle again;

determining a zero position of the motor according to the first angle, the second angle, and the third angle includes:

calculating the average value of the obtained multiple groups of second angles and third angles;

and taking the difference value of the first angle and the average value as the zero position of the motor.

According to a second aspect of the embodiments of the present disclosure, there is provided an apparatus for determining a zero position of a motor, the apparatus including:

the first angle determining module is used for determining a first angle of a rotor of the motor when the rotor reaches a preset position after the motor is electrified according to a preset first duty ratio and a first current value;

the current zero clearing module is used for controlling the current zero clearing of the motor;

the angle acquisition module is further used for controlling the motor to run for a first preset time in an inertia state after the rotating speed of the motor reaches a first preset rotating speed in forward rotation so as to acquire a second angle of the rotor after the first preset time is finished;

the angle acquisition module is further configured to control the motor to operate for a second preset time in an inertial state after the rotation speed of the motor reaches a second preset rotation speed during reverse rotation, so as to acquire a third angle of the rotor after the second preset time is completed;

and the zero position determining module is used for determining the zero position of the motor according to the first angle, the second angle and the third angle.

Optionally, the first angle determining module includes:

the duty ratio setting submodule is used for setting the duty ratio of each phase of the motor according to the first duty ratio;

the energization submodule is used for energizing the motor according to the first current value after the duty ratio of each phase is set;

the angle determining submodule is used for determining the first angle according to the preset position when the rotor reaches the preset position;

and the angle writing submodule is used for writing the first angle into a control program of the motor.

Optionally, the current zero module includes:

the duty ratio setting submodule is used for setting the duty ratio of each phase of the motor as the initial duty ratio;

and the current zero clearing submodule is used for controlling the current output of the motor to be zero by utilizing the initial duty ratio.

Optionally, the angle obtaining module includes:

the rotating speed control submodule is used for controlling the rotating speed of the motor to reach the first preset rotating speed in the forward rotation process by utilizing a first current control instruction;

the operation control submodule is used for controlling the motor to operate for the first preset time in an inertial state by utilizing a second current control instruction;

the voltage acquisition submodule is used for acquiring a first direct-axis voltage and a first quadrature-axis voltage of the motor after the first preset time is finished;

the angle determining submodule is used for determining the second angle according to the first direct-axis voltage and the first quadrature-axis voltage;

and the angle writing submodule is used for writing the second angle into a control program of the motor.

Optionally, the angle obtaining module includes:

the rotating speed control submodule is also used for controlling the rotating speed of the motor to be reduced to an initial rotating speed value by utilizing a third current control instruction;

the current zero clearing submodule is used for clearing the current of the motor by utilizing a fourth current control instruction;

the rotating speed control submodule is also used for controlling the rotating speed of the motor to reach the second preset rotating speed when the motor rotates reversely by using a fifth current control instruction;

the operation control sub-module is further used for controlling the motor to operate for the second preset time in an inertial state by using a sixth current control instruction;

the voltage obtaining submodule is further used for obtaining a second direct-axis voltage and a second quadrature-axis voltage of the motor after the second preset time is finished;

the angle determining submodule is further configured to determine the third angle according to the second direct-axis voltage and the second quadrature-axis voltage;

and the angle writing submodule is also used for writing the third angle into a control program of the motor.

Optionally, the apparatus further comprises:

the rotating speed control module is used for controlling the rotating speed of the motor to be reduced to an initial rotating speed value by utilizing a seventh current control instruction after the third angle is obtained;

the current zero clearing module is further used for clearing the current of the motor by using an eighth current control instruction.

Optionally, the apparatus further comprises:

the repeated execution module is used for repeatedly executing the step of controlling the rotating speed of the motor to reach a first preset rotating speed during forward rotation and then operating the motor for a first preset time in the inertia state so as to obtain a second angle of the rotor after the first preset time is finished and the step of controlling the rotating speed of the motor to reach a second preset rotating speed during reverse rotation and then operating the motor for a second preset time in the inertia state so as to obtain a third angle of the rotor after the second preset time is finished at least once so as to obtain at least one group of second angle and third angle again;

the zero determination module is configured to:

calculating the average value of the obtained multiple groups of second angles and third angles;

and taking the difference value of the first angle and the average value as the zero position of the motor.

According to the technical scheme, after the motor is electrified, the first angle of the rotor when the rotor of the motor reaches the preset position is determined according to the preset first duty ratio and the first current value; controlling the current of the motor to be reset; controlling the rotating speed of the motor to reach a first preset rotating speed in forward rotation and then operating for a first preset time in an inertial state so as to obtain a second angle of the rotor after the first preset time is finished; controlling the rotating speed of the motor to reach a second preset rotating speed during reverse rotation and then operating for a second preset time in an inertial state so as to obtain a third angle of the rotor after the second preset time is finished; and determining a zero position of the motor according to the first angle, the second angle and the third angle. The zero position of the motor can be effectively determined by measuring the angles of the motor in forward rotation and reverse rotation, real-time online processing is utilized, the accuracy of a measuring result is further improved, manual correction is not needed, the operation is simple and convenient, and the time, the labor and the equipment cost are saved.

Additional features and advantages of the disclosure will be set forth in the detailed description which follows.

Drawings

The accompanying drawings, which are included to provide a further understanding of the disclosure and are incorporated in and constitute a part of this specification, illustrate embodiments of the disclosure and together with the description serve to explain the disclosure without limiting the disclosure. In the drawings:

FIG. 1 is a schematic diagram of an electric drive bridge according to an exemplary embodiment;

FIG. 2 is a flow chart illustrating a method of determining a zero position of a motor in accordance with an exemplary embodiment;

FIG. 3 is a flow chart illustrating another method of motor zero determination in accordance with an exemplary embodiment;

FIG. 4 is a flow chart illustrating yet another method of motor zero determination in accordance with an exemplary embodiment;

FIG. 5 is a flow chart illustrating yet another method of motor zero determination in accordance with an exemplary embodiment;

FIG. 6 is a flow chart illustrating yet another method of motor zero determination in accordance with an exemplary embodiment;

FIG. 7 is a flow chart illustrating yet another method of motor zero determination in accordance with an exemplary embodiment;

FIG. 8 is a flow chart illustrating yet another method of motor zero determination in accordance with an exemplary embodiment;

FIG. 9 is a block diagram illustrating an apparatus for determining a zero position of a motor in accordance with an exemplary embodiment;

FIG. 10 is a block diagram illustrating a first angle determination module in accordance with an exemplary embodiment;

FIG. 11 is a block diagram illustrating a current zero module in accordance with an exemplary embodiment;

FIG. 12 is a block diagram illustrating an angle acquisition module in accordance with an exemplary embodiment;

FIG. 13 is a block diagram illustrating another angle acquisition module in accordance with an exemplary embodiment;

FIG. 14 is a block diagram illustrating another motor zero position determination arrangement in accordance with an exemplary embodiment;

FIG. 15 is a block diagram illustrating yet another motor zero position determination arrangement in accordance with an exemplary embodiment.

Detailed Description

The following detailed description of specific embodiments of the present disclosure is provided in connection with the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the present disclosure, are given by way of illustration and explanation only, not limitation.

Before introducing the embodiment of the present disclosure, an application scenario of the technical solution of the present disclosure is first introduced, where a structure of an electric drive bridge is as shown in fig. 1, when testing a zero position of a motor therein, the electric drive bridge needs to be fixed on a tool to prevent the electric drive bridge from rolling due to movement, which brings danger, and power is supplied to a bus side of a motor controller, so that the motor controller drives the motor to rotate, that is, a dc power supply is added to a dc power supply side to implement a zero position test of the motor.

When the zero position of the motor is accurate, the motor stably runs at a certain rotating speed in a steady state, a current command Id (direct-axis current) is 0, Iq (quadrature-axis current) is 0 is applied to the motor controller, and according to a voltage calculation formula of the motor, the direct-axis voltage can be determined to be zero Ud and 0, and the quadrature-axis voltage is a fixed value. However, when the zero position of the motor is inaccurate, for example, there is a deviation angle theta of the zero position, and the motor stably operates in a steady state at a certain rotation speed, the current command Id is 0 and Iq is 0 are also applied to the motor controller, at this time, the direct-axis voltage is no longer zero, the quadrature-axis voltage is also not fixed, and a functional relationship depending on theta exists between the direct-axis voltage and the quadrature-axis voltage, that is, the ratio of the direct-axis voltage to the quadrature-axis voltage is the tangent value of theta. The present disclosure provides a simple and easy technical scheme, which effectively tests the deviation angle theta of the zero position, and then controls and adjusts the motor to overcome the influence of the deviation angle of the zero position on the normal operation of the motor.

FIG. 2 is a flow chart illustrating a method for determining a zero position of a motor, as shown in FIG. 2, according to an exemplary embodiment, the method comprising the steps of:

step 201, according to a preset first duty ratio and a first current value, after the motor is powered on, determining a first angle of the rotor when the rotor of the motor reaches a preset position.

By way of example, with a preset first duty cycle and a first current value, a rough determination of the zero position of the energized electric machine is achieved, since the three-phase synchronous motor includes a three-phase stator winding and a rotor (a rotor winding is provided on the rotor), the phase difference between each two phase windings of the three-phase stator winding is 120 degrees, the first current value includes the respective current values of the three phases, i.e., a-phase current value, a B-phase current value, and a C-phase current value, which are current values applied to both ends of the three-phase stator winding, respectively, the first duty includes duty ratios of the three phases, respectively, namely, the duty ratio of the A phase, the duty ratio of the B phase and the duty ratio of the C phase, the duty ratios of the three phases refer to the proportion of the power-on time of the voltages at two ends of the three-phase stator winding in one power-on and power-off period, the voltage at the two ends of the three-phase stator winding can be adjusted by adjusting the duty ratio of each phase. That is, the first duty ratio is different from the initial duty ratio of the motor, and the first current value is used for rotating the motor so that the rotor of the motor reaches a preset position, so as to determine the first angle of the rotor at the preset position.

In addition, it should be noted that after the first angle is determined, the first angle also needs to be written into a control program of the motor, so that the calculation is called when the zero position of the motor is determined in the following step.

And step 202, controlling the current of the motor to be cleared.

For example, after the rough zero position measurement is completed, and the first angle is obtained, the current of the motor needs to be cleared, and the duty ratio may be restored to the initial duty ratio, for example, the duty ratio of the a phase is 16384, the duty ratio of the B phase is 16384, and the duty ratio of the C phase is 16384, and then the current is cleared, so as to perform the subsequent measurement again.

And 203, controlling the rotating speed of the motor to reach a first preset rotating speed in forward rotation and then operating for a first preset time in an inertial state, so as to obtain a second angle of the rotor after the first preset time is finished.

For example, after the current of the motor is cleared, the deviation angle of the zero position of the motor is measured, a motor controller issues a first current control command to the motor, for example, Id is 0, Iq is TBD (a preset value, which is a positive value), so that the motor rotates in an idle state until the rotation speed reaches a preset rotation speed; and after the preset rotating speed is reached, the second current control command Id is 0, and Iq is 0, so that the tested motor loses power, the first preset time can be operated in an inertial state, a second angle is determined in the first preset time, the operation is different from the operation in the step 201, and the accurate measurement is performed in the forward rotation process after the motor is operated for a period of time.

In addition, after the measurement is completed, a second angle is also written into the control program of the electric machine, so that the subsequent steps are used to determine the zero position of the electric machine.

And 204, controlling the rotating speed of the motor to run for a second preset time in the inertia state after reaching a second preset rotating speed in the reverse rotation so as to obtain a third angle of the rotor after the second preset time is finished.

For example, the present disclosure may be applied to a case where the driving system has a motor that operates in two directions, so that the motor reaches the first preset rotation speed to determine the second angle in the forward rotation of the motor in step 203, and the corresponding current control command is used to enable the motor to reach the second preset rotation speed to determine the third angle in the reverse rotation of the motor, so as to determine the deviation angle of the zero position in the forward rotation direction and the reverse rotation direction, thereby improving the measurement accuracy.

And step 205, determining the zero position of the motor according to the first angle, the second angle and the third angle.

For example, the difference between the first angle and the average of the second angle and the third angle is taken as the zero position of the motor. The first angle can be regarded as a factory zero position of the motor when the motor leaves a factory, and the factory zero position is corrected through an average value of the second angle and the third angle obtained through forward rotation and reverse rotation, so that the accurate zero position of the motor can be determined.

In summary, according to the method for determining the zero position of the motor, provided by the present disclosure, after the motor is powered on, according to a preset first duty ratio and a first current value, a first angle of a rotor when the rotor of the motor reaches a preset position is determined; current zero clearing of the control motor; after the current of the motor is cleared, controlling the rotating speed of the motor to reach a first preset rotating speed during forward rotation and then operating for a first preset time in an inertial state so as to obtain a second angle of the rotor after the first preset time is finished; controlling the rotating speed of the motor to reach a second preset rotating speed during reverse rotation and then operating for a second preset time in an inertial state so as to obtain a third angle of the rotor after the second preset time is finished; and determining the zero position of the motor according to the first angle, the second angle and the third angle. The zero position of the motor can be effectively determined by measuring the angles of the motor in forward rotation and reverse rotation, real-time online processing is utilized, the accuracy of a measuring result is further improved, manual correction is not needed, the operation is simple and convenient, and the time, the labor and the equipment cost are saved.

Fig. 3 is a flowchart illustrating another method for determining a zero position of a motor according to an exemplary embodiment, where, as shown in fig. 3, determining a first angle of the motor when a rotor of the motor reaches a preset position after the motor is energized according to a preset first duty cycle and a first current value in step 201 includes:

in step 2011, the duty cycle of each phase of the motor is set according to the first duty cycle.

For example, the first duty cycle may be different from the initial duty cycle and may be set to be three-phase asymmetric, that is, three-phase duty cycles are not uniform, for example: the duty ratio of the a phase is 14384, the duty ratio of the B phase is 18384, and the duty ratio of the C phase is 18384, so that the duty ratio difference between the AB phase is 4000, the duty ratio difference between the AC phase is 4000, and the duty ratio difference between the BC phase is 0, and the switching time of the thyristor is controlled according to such duty ratios, and the current flow in the following step 2012 is correspondingly generated.

Step 2012, after the duty ratio of each phase is set, the motor is energized according to the first current value.

In step 2011, according to the duty ratio, the corresponding first current value is, for example, Ia (a-phase current value) — 2Ib (B-phase current value) — 2Ic (C-phase current value), that is, in the case of the asymmetric first duty ratio, the phase a of the measured motor is positively charged, the phase B of the measured motor is negatively charged, and the phase C of the measured motor is negatively charged, so as to rotate the motor.

Step 2013, when the rotor reaches the preset position, determining a first angle according to the preset position.

For example, when the motor is energized such that the rotor reaches a predetermined position, i.e. a position of a predetermined identification of the motor system, for example D1 or D2, the angle of the rotor is determined as a first angle, i.e. a roughly detectable zero position of the motor.

Step 2014, writing the first angle in a control program of the motor.

The determined first angle is written, for example, into a control program of the electric machine for later recall.

Fig. 4 is a flow chart illustrating a method for determining a zero position of a motor according to an exemplary embodiment, where the current of the motor is controlled to be zero in step 202, as shown in fig. 4, and the method includes the following steps:

step 2021, set the duty cycle of each phase of the motor to the initial duty cycle.

Step 2022, controlling the current output of the motor to be zero using the initial duty cycle.

For example, after the step 201 completes the test of the zero position of the motor once, the current of the motor needs to be cleared for the subsequent test.

Fig. 5 is a flowchart illustrating a method for determining a zero position of a motor according to an exemplary embodiment, where as shown in fig. 5, the step 203 of controlling the rotation speed of the motor to reach a first preset rotation speed in the forward rotation and then operating in the inertia state for a first preset time to obtain a second angle of the rotor after the first preset time is completed includes the following steps:

step 2031, controlling the rotation speed of the motor in the forward rotation to reach a first preset rotation speed by using the first current control instruction.

For example, after the current of the motor is cleared, the measurement of the zero position when the motor rotates forward is started, and the motor may rotate in a no-load manner by using a first current control command, such as Id ═ 0 and Iq ═ TBD, until the rotation speed reaches the preset rotation speed.

And 2032, controlling the motor to operate for a first preset time in an inertial state by using the second current control instruction.

For example, after the rotation speed of the motor reaches the preset rotation speed, the second current control command, i.e., the current zero clearing command, is utilized to enable the motor to lose power and operate in the inertia state for a preset time, for example, 5 s. It should be noted here that, since the setting of the preset rotation speed may affect the test result of the technical solution of the present disclosure, the preset rotation speed is determined according to the characteristics and experience of the motor itself, so that when the motor runs through inertia near the preset rotation speed, sudden change of the rotation speed or other unstable factors may not occur.

Step 2033, after the first preset time is finished, obtaining a first direct axis voltage and a first quadrature axis voltage of the motor.

Illustratively, the direct-axis voltage and the quadrature-axis voltage of the motor will be acquired after the first preset time is completed, i.e. as the first direct-axis voltage and the first quadrature-axis voltage, so as to determine the second angle through processing and calculation.

Step 2034, determining a second angle according to the first direct voltage and the first quadrature voltage.

For example, as described above, when the zero position of the motor is inaccurate, it may be known that the ratio of the direct-axis voltage to the quadrature-axis voltage is a tangent value of theta according to a voltage calculation formula of the motor, so that an effective voltage value is determined through filtering, and then an arctangent calculation is performed on the ratio of the first direct-axis voltage to the first quadrature-axis voltage after filtering, where the arctangent calculation is performed through a trigonometric function calculation, and an arctangent value obtained by calculating the ratio of the first direct-axis voltage to the first quadrature-axis voltage as a second angle, which is denoted as theta2, may be represented as:

wherein U is _dIs the first direct voltage and U _qFor the first quadrature voltage, a second angle is obtained.

Step 2035, writing the second angle in the control program of the motor.

And writing the second angle into a control program of the motor for calculation in the subsequent step.

Fig. 6 is a flowchart illustrating a method for determining a zero position of a motor according to an exemplary embodiment, where, as shown in fig. 6, the step 204 of controlling the rotation speed of the motor to reach a second preset rotation speed during reverse rotation and then operating in an inertia state for a second preset time to obtain a third angle of the rotor after the second preset time is completed includes the following steps:

and 2041, controlling the rotating speed of the motor to be reduced to an initial rotating speed value by using a third current control instruction.

After the second angle is obtained in step 203, the rotation speed of the motor is cleared by a third current control command, which may be, for example, Id 0, Iq TBD (equal to the first current control command in magnitude and opposite in direction), and the rotation speed of the motor is further decreased to an initial rotation speed, that is, 0, and the magnitude of the quadrature axis current value TBD may be selected to be different from the magnitude of the quadrature axis current of the first current control command.

And step 2042, clearing the current of the motor by using a fourth current control instruction.

For example, after the speed is cleared, the current of the motor needs to be cleared again, the fourth current control command Id is 0, and Iq is 0, so that the following remeasurement is prepared.

And 2043, controlling the rotating speed of the motor to reach a second preset rotating speed in the reverse rotation process by using a fifth current control instruction.

Illustratively, the fifth current control command, Id is 0, and Iq is-TBD 1 (a preset value, negative, making the motor reverse), and then reaches the first preset rotation speed at the time of reverse rotation.

And 2044, controlling the motor to operate in an inertia state for a second preset time by using the sixth current control instruction.

Illustratively, the second preset time may coincide with the first preset time, i.e., 5 s.

And 2045, acquiring a second direct axis voltage and a second quadrature axis voltage of the motor after the second preset time is finished.

Step 2046, determine a third angle according to the second direct axis voltage and the second quadrature axis voltage.

And step 2047, writing the third angle into a control program of the motor.

For example, the step of determining the third angle is consistent with the step of determining the second angle shown in fig. 5, and is not described herein again.

FIG. 7 is a flow chart illustrating yet another method for determining a zero position of a motor, as shown in FIG. 7, in accordance with an exemplary embodiment, the method further comprising the steps of:

and step 206, after the third angle is obtained, the rotating speed of the motor is controlled to be reduced to the initial rotating speed value by using a seventh current control instruction.

For example, after the third angle is obtained, the seventh current control command, for example, the reverse command of the fifth current control command, is used to make Id equal to 0 and Iq equal to TBD1 (equal to the magnitude and opposite to the sign of the quadrature axis current of the fifth current control command), so that the rotation speed of the motor under test can be rapidly reduced to 0.

And step 207, utilizing an eighth current control command to control the current of the motor to be cleared.

For example, the initial value of the rotation speed is 0, that is, after the rotation speed of the motor is rapidly reduced to 0 in step 206, the motor controller applies an eighth current command to the motor, for example, Id is 0 and Iq is 0, that is, after the rotation speed of the motor is cleared, the current is cleared.

That is, after the zero position determination of the motor in the embodiment of fig. 2 is completed, the motor is initialized to resume the initial state operation through the above steps 206 and 207, and the rotation speed and the current of the motor are sequentially cleared for the subsequent normal use.

FIG. 8 is a flow chart illustrating yet another method for determining a zero position of a motor, as shown in FIG. 8, prior to step 205, the method further comprising the steps of:

and step 208, repeating the step 203 and the step 204 at least once to acquire at least one set of the second angle and the third angle again.

For example, in order to further improve the accuracy of the technical scheme of the present disclosure, step 203 and step 204 are repeatedly executed, that is, a plurality of angles of the rotor of the motor when the motor rotates forward to reach a plurality of different preset rotation speeds and a plurality of angles of the rotor of the motor when the motor rotates backward to reach a plurality of different preset rotation speeds are measured, filtering and mean value processing are performed by using a statistical method, a more accurate measurement result is obtained, and then zero position when the motor leaves the factory is corrected, so that the accuracy of the zero position of the motor determined in this step is better improved. For example, when the motor rotates forward, the operation of step 203 is repeated to make the rotation speed of the motor sequentially reach the third preset rotation speed and the fourth preset rotation speed to obtain the fourth angle and the fifth angle, then the motor rotates backward, the operation of step 204 is repeated to make the rotation speed sequentially reach the fifth preset rotation speed and the sixth preset rotation speed, then after the motor operates in the inertia state for a preset time, the corresponding sixth angle and seventh angle are obtained, then the values of the second angle to the seventh angle are averaged, and the average value is used as the correction of the factory zero position.

Optionally, the determining the zero position of the motor according to the first angle, the second angle and the third angle in step 205 includes the following steps:

and step 2051, calculating an average value of the acquired multiple groups of second angles and third angles.

Step 2052, the difference between the first angle and the average value is used as the zero position of the motor.

In summary, according to the method for determining the zero position of the motor, provided by the present disclosure, after the motor is powered on, according to a preset first duty ratio and a first current value, a first angle of a rotor when the rotor of the motor reaches a preset position is determined; current zero clearing of the control motor; controlling the rotating speed of the motor to reach a first preset rotating speed in forward rotation and then operating for a first preset time in an inertial state so as to obtain a second angle of the rotor after the first preset time is finished; controlling the rotating speed of the motor to reach a second preset rotating speed during reverse rotation and then operating for a second preset time in an inertial state so as to obtain a third angle of the rotor after the second preset time is finished; and determining the zero position of the motor according to the first angle, the second angle and the third angle. The zero position of the motor can be effectively determined by measuring the angles of the motor in forward rotation and reverse rotation, real-time online processing is utilized, the accuracy of a measuring result is further improved, manual correction is not needed, the operation is simple and convenient, and the time, the labor and the equipment cost are saved.

FIG. 9 is a block diagram illustrating an apparatus for determining a zero position of a motor in accordance with an exemplary embodiment. Referring to fig. 9, for implementing the embodiment described in any of fig. 2-8, the apparatus 900 includes:

the first angle determining module 910 is configured to determine, according to a preset first duty ratio and a first current value, a first angle of a rotor when the rotor of the motor reaches a preset position after the motor is powered on.

And a current zero clearing module 920, configured to control current zero clearing of the motor.

The angle obtaining module 930 is configured to control the rotation speed of the motor to reach a first preset rotation speed in the forward rotation and then operate in the inertia state for a first preset time, so as to obtain a second angle of the rotor after the first preset time is completed.

The angle obtaining module 930 is further configured to control the motor to operate in the inertia state for a second preset time after the rotation speed of the motor reaches a second preset rotation speed during the reverse rotation, so as to obtain a third angle of the rotor after the second preset time is completed.

And a zero position determining module 940, configured to determine a zero position of the motor according to the first angle, the second angle, and the third angle.

FIG. 10 is a block diagram illustrating a first angle determination module in accordance with an exemplary embodiment. Referring to fig. 10, the first angle determining module 910 includes:

and the duty ratio setting submodule 911 is used for setting the duty ratio of each phase of the motor according to the first duty ratio.

And the energizing submodule 912 is configured to energize the motor according to the first current value after the duty ratio of each phase is set.

The angle determining submodule 913 is configured to determine the first angle according to the preset position when the rotor reaches the preset position.

The angle writing submodule 914 is configured to write the first angle into a control program of the motor.

FIG. 11 is a block diagram illustrating a current zero module in accordance with an exemplary embodiment. Referring to fig. 11, the current zero clearing module 920 includes:

and a duty ratio setting submodule 921 for setting the duty ratio of each phase of the motor to the initial duty ratio.

And the current zero clearing submodule 922 is used for controlling the current output of the motor to be zero by utilizing the initial duty ratio.

FIG. 12 is a block diagram illustrating an angle acquisition module in accordance with an exemplary embodiment. Referring to fig. 12, the angle obtaining module 930 includes:

and the rotation speed control submodule 931 is configured to control, by using the first current control instruction, the rotation speed of the motor in the forward rotation to reach a first preset rotation speed.

And the operation control submodule 932 is used for controlling the motor to operate for a first preset time in the inertia state by using the second current control instruction.

The voltage obtaining submodule 933 is configured to obtain a first direct-axis voltage and a first quadrature-axis voltage of the motor after the first preset time is completed.

The angle determination submodule 934 is configured to determine a second angle according to the first direct-axis voltage and the first quadrature-axis voltage.

The angle writing submodule 935 is configured to write the second angle into the control program of the motor.

FIG. 13 is a block diagram illustrating another angle acquisition module in accordance with an exemplary embodiment. Referring to fig. 13, the angle obtaining module 930 includes:

the rotation speed control submodule 931 is further configured to control the rotation speed of the motor to be reduced to the rotation speed initial value by using the third current control command.

And a current zero sub-module 936 for zero-clearing the current of the motor by using the fourth current control command.

The rotation speed control submodule 931 is further configured to control the rotation speed of the motor during the reverse rotation to reach the second preset rotation speed by using the fifth current control instruction.

The operation control sub-module 932 is further configured to control the motor to operate in the inertia state for a second preset time according to the sixth current control command.

The voltage obtaining submodule 933 is further configured to obtain a second direct-axis voltage and a second quadrature-axis voltage of the motor after the second preset time is completed.

The angle determination submodule 934 is further configured to determine a third angle according to the second direct-axis voltage and the second quadrature-axis voltage.

The angle writing sub-module 935 is further configured to write the third angle in the control program of the motor.

FIG. 14 is a block diagram illustrating another motor zero position determination arrangement in accordance with an exemplary embodiment. Referring to fig. 14, the apparatus 900 further includes:

and the rotation speed control module 950 is configured to control the rotation speed of the motor to be reduced to the initial rotation speed value by using the seventh current control instruction after the third angle is obtained.

The current zero clearing module 920 is further configured to zero the current of the motor by using an eighth current control instruction.

FIG. 15 is a block diagram illustrating yet another motor zero position determination arrangement in accordance with an exemplary embodiment. Referring to fig. 15, the apparatus 900 further includes:

the repeated execution module 960 is configured to repeatedly execute the step of controlling the rotation speed of the motor to reach a first preset rotation speed during forward rotation and then operate in the inertia state for a first preset time, so as to obtain the second angle of the rotor after the first preset time is completed, and operate in the inertia state for a second preset time after the rotation speed of the motor reaches a second preset rotation speed during reverse rotation, so as to obtain the third angle of the rotor at least once after the second preset time is completed, so as to obtain at least one set of the second angle and the third angle again.

A zero determination module 940 for:

calculating the average value of the obtained multiple groups of second angles and third angles; and taking the difference value of the first angle and the average value as the zero position of the motor.

In summary, according to the device for determining the zero position of the motor provided by the present disclosure, after the motor is powered on, according to the preset first duty ratio and the first current value, the first angle of the rotor when the rotor of the motor reaches the preset position is determined; current zero clearing of the control motor; controlling the rotating speed of the motor to reach a first preset rotating speed in forward rotation and then operating for a first preset time in an inertial state so as to obtain a second angle of the rotor after the first preset time is finished; controlling the rotating speed of the motor to reach a second preset rotating speed during reverse rotation and then operating for a second preset time in an inertial state so as to obtain a third angle of the rotor after the second preset time is finished; and determining the zero position of the motor according to the first angle, the second angle and the third angle. The zero position of the motor can be effectively determined by measuring the angles of the motor in forward rotation and reverse rotation, real-time online processing is utilized, the accuracy of a measuring result is further improved, manual correction is not needed, the operation is simple and convenient, and the time, the labor and the equipment cost are saved.

With regard to the apparatus in the above-described embodiment, the specific manner in which each module performs the operation has been described in detail in the embodiment related to the method, and will not be elaborated here.

The preferred embodiments of the present disclosure are described in detail with reference to the accompanying drawings, however, the present disclosure is not limited to the specific details of the above embodiments, and various simple modifications may be made to the technical solution of the present disclosure within the technical idea of the present disclosure, and these simple modifications all belong to the protection scope of the present disclosure.

It should be noted that the various features described in the above embodiments may be combined in any suitable manner without departing from the scope of the invention. In order to avoid unnecessary repetition, various possible combinations will not be separately described in this disclosure.

In addition, any combination of various embodiments of the present disclosure may be made, and the same should be considered as the disclosure of the present disclosure, as long as it does not depart from the spirit of the present disclosure.