CN117559866A - Zero angle calibration method for power splitting hybrid gearbox offline motor - Google Patents

Abstract

The invention relates to the technical field of motor control, in particular to a zero angle calibration method for a power split hybrid gearbox offline motor, which comprises the following steps: (1) Setting the idle load rotating speed of the hybrid gearbox, and carrying out initial angle assignment theta; (2) Reading zero offset torque Ts of the motor at the idle rotation speed through the PEU; (3) giving the direct-axis current id of the motor to be tested through the PEU; (4) Reading the real-time torque Tr of the motor through the PEU, and comparing the real-time torque Tr with the zero offset torque Ts in the step (2) to obtain a torque difference DeltaT; judging whether the delta T is smaller than or equal to a torque set value, if not, adjusting the zero angle of the motor; if yes, go to step (5); (5) Increasing the direct-axis current id of the motor to be tested to a current set value through the PEU, judging whether the direct-axis current id of the motor to be tested is smaller than or equal to the current set value, and returning to the step (4) if not; if yes, the calibration is completed. The method has the advantages of quick angle identification and calibration time, strong applicability, low dependence on software algorithm and high learning accuracy.

Description

Zero angle calibration method for power splitting hybrid gearbox offline motor

Technical Field

The invention relates to the technical field of motor control, in particular to a zero angle calibration method for a power split hybrid gearbox off-line motor.

Background

According to vector control of a permanent magnet synchronous motor, in order to maximize torque output by the motor, a rotor position angle needs to be accurately obtained. For the precision of zero offset of the rotary sensor, the rotary transmission zero offset and the actual zero offset of the motor rotor can be ensured in an ideal state, but in the actual motor production process, machining offset and installation offset exist, so that the installation and positioning of the rotary sensor are inconsistent, and the deflection angles of the rotary sensor of each motor are inconsistent. The zero angle deviation of the motor can influence the performance of the motor, for example, vibration and noise of the motor during starting can be caused, and the efficiency and precision of the motor are reduced, so that the motor needs zero angle deviation calibration during offline detection.

Currently, there are generally 3 ways to zero identify or calibrate a motor or hybrid transmission off-line motor:

1. static measurement: a low-voltage direct current is firstly supplied to the motor winding, the U phase is connected positively, the V phase or the VW phase is connected negatively, and at the moment, the motor rotor is pulled to a fixed position. The zero offset of the rotation and the motor is obtained by reading the rotation resolving angle value at the moment. The method has the problems that a set of direct current power supply equipment is required to be added independently, or a motor controller is used for direct current output, but the method is only suitable for a single motor with small friction resistance, for a hybrid power transmission, as a multi-stage shaft tooth structure exists, the friction resistance is large, whether a zero position is accurate or not is required to be determined through comparison of results of 2 to 3 times, the angle calibration time is required to be more than 300 seconds, and the production beat is seriously influenced;

2. dynamic measurement: pulling a tested motor or a hybrid power gearbox to a certain rotating speed by using a rack or a counter-pulling motor, and measuring counter electromotive force and a phase difference of a rotary change signal;

3. high frequency injection: dividing 360 DEG into 12 equal parts, injecting voltage vectors with equal amplitude and equal time into a motor winding under different angles to obtain a current value, transforming the current value to an assumed DQ axis coordinate, and transforming the back-clamp and the park to obtain an Id value, wherein the angle at the maximum Id is a value close to the zero angle of an accurate motor, and repeatedly applying the steps between theta+/-15 DEG by using a bisection method to obtain theta 1 until the precision requirement is met, but the method has higher requirement on a software algorithm, and most motor controller manufacturers learn deviation reaches more than 3 DEG, so that the precision requirement of +/-1 DEG cannot be met.

Therefore, a new solution is needed to solve the above technical problems.

Disclosure of Invention

The invention aims to solve the problems in the prior art, and provides a zero angle calibration method for a power splitting hybrid gearbox offline motor, which is used for solving the technical problems that in the prior art, additional special tools or equipment are required to be added for zero position identification or calibration of the motor or the hybrid gearbox offline motor, the zero angle learning and calibration time of the motor is long, special persons or special stations are required to be arranged for operation, the dependence on software algorithm is high, the algorithm quality seriously affects the result, and the accuracy is insufficient.

The above purpose is realized by the following technical scheme:

a zero angle calibration method for a power split hybrid gearbox off-line motor comprises the following steps:

step (1) giving the idle load rotating speed of the hybrid gearbox, and carrying out initial angle assignment theta;

step (2) reading zero offset torque Ts of the motor at the idle rotation speed through the PEU;

step (3), giving the direct-axis current id of the motor to be tested through the PEU;

step (4) reading real-time torque Tr of a motor through a PEU, and comparing the real-time torque Tr with the zero offset torque Ts in the step (2) to obtain a torque difference DeltaT; judging whether the delta T is smaller than or equal to a torque set value, if not, adjusting the zero angle of the motor; if yes, go to step (5);

step (5) increasing the direct-axis current id of the motor to be tested to a current set value through the PEU, judging whether the current direct-axis current id of the motor to be tested is smaller than or equal to the current set value, and returning to the step (4) if not; if yes, the calibration is completed.

Further, in step (4), a delay of 200ms (TBD) is required between the obtained torque difference Δt and the determination Δt| being equal to or less than a torque set point.

Further, the torque set point is 1.5Nm (TBD).

Further, in the step (5), whether the current measured motor direct axis current id is smaller than or equal to the current set value or not is judged, and a time delay of 200ms is required between the step (4) of returning.

Further, the current set point is-300A (TBD).

Further, the adjusting the zero angle of the motor in the step (4) specifically includes:

step (4-1) confirms whether DeltaT is more than or equal to 0, if so, entering step (4-2); if not, entering the step (4-3);

step (4-2) confirms whether DeltaT is more than or equal to 10Nm (TBD), if so, the zero angle of the adjusting motor is increased by 0.32 degrees; if not, the zero angle of the adjusting motor is increased by 0.05 degrees; after the completion, the step (4-4) is carried out;

step (4-3) confirms whether DeltaT is less than or equal to minus 10Nm (TBD), if so, the zero angle of the adjusting motor is reduced by 0.32 degrees; if not, the zero angle of the adjusting motor is reduced by 0.05 degrees; after the completion, the step (4-4) is carried out;

step (4-4) reads the current motor real-time torque Tr through the PEU, confirms whether the delta T is smaller than or equal to a torque set value, and if yes, enters step (4); if not, returning to the step (4-1).

Advantageous effects

According to the zero angle calibration method for the power splitting hybrid gearbox offline motor, provided by the invention, the zero angle calibration of the motor is realized without increasing any cost by relying on the existing conventional motor and hybrid gearbox offline detection equipment resources; the zero angle calibration time of the motor can be compressed to 30s; in addition, the software logic of the calibration scheme is simple to realize, the angle precision can reach +/-0.5 degrees, and the consistency is good after 1000 times of inspection.

Drawings

FIG. 1 is a flow chart of a zero angle calibration method for an offline motor of a power splitting hybrid gearbox according to the present invention;

fig. 2 is a schematic diagram of a zero angle calibration method for an offline motor of a power splitting hybrid gearbox according to the present invention.

Detailed Description

The invention is described in further detail below with reference to the drawings and examples. The described embodiments are only some, but not all, embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

As shown in fig. 1, the present solution provides a zero angle calibration method for a power splitting hybrid gearbox offline motor, which uses the principle that PMSM (permanent-magnet synchronous machine, abbreviated as PMSM, refers to a synchronous motor in which a rotor uses permanent magnets instead of wound wires) does not generate electromagnetic moment given iq=0, and combines with a pilot-test bench resource to calibrate the motor angle, and includes the following steps:

step (1) giving the idle load rotating speed of the hybrid gearbox, and carrying out initial angle assignment theta;

step (2) reading zero offset torque Ts of the motor at the idle rotation speed through the PEU;

step (3), giving the direct-axis current id of the motor to be tested through the PEU;

step (4) reading real-time torque Tr of a motor through a PEU, and comparing the real-time torque Tr with the zero offset torque Ts in the step (2) to obtain a torque difference DeltaT; judging whether the delta T is smaller than or equal to a torque set value, if not, adjusting the zero angle of the motor; if yes, go to step (5);

step (5) increasing the direct-axis current id of the motor to be tested to a current set value through the PEU, judging whether the current direct-axis current id of the motor to be tested is smaller than or equal to the current set value, and returning to the step (4) if not; if yes, the calibration is completed.

In the step (4), a delay of 200ms (TBD) is required between the obtained torque difference Δt and the determination Δt| being less than or equal to a torque set value.

As a specific example of the torque set point, the torque set point is 1.5Nm (TBD).

And in the step (5), judging whether the current value id of the direct axis of the motor to be tested is smaller than or equal to a current set value, and delaying 200ms between the current value id and the returning step (4).

As a specific example of the current set point, the current set point is-300A (TBD).

As the operation of adjusting the zero angle of the motor in the step (4) in this embodiment, the method specifically includes:

step (4-1) confirms whether DeltaT is more than or equal to 0, if so, entering step (4-2); if not, entering the step (4-3);

step (4-2) confirms whether DeltaT is more than or equal to 10Nm (TBD), if so, the zero angle of the adjusting motor is increased by 0.32 degrees; if not, the zero angle of the adjusting motor is increased by 0.05 degrees; after the completion, the step (4-4) is carried out;

step (4-3) confirms whether DeltaT is less than or equal to minus 10Nm (TBD), if so, the zero angle of the adjusting motor is reduced by 0.32 degrees; if not, the zero angle of the adjusting motor is reduced by 0.05 degrees; after the completion, the step (4-4) is carried out;

step (4-4) reads the current motor real-time torque Tr through the PEU, confirms whether the delta T is smaller than or equal to a torque set value, and if yes, enters step (4); if not, returning to the step (4-1).

As shown in fig. 2, for the policy study of the present scheme, EM2 is taken as a specific example, and is described as follows:

1. the output motor is accelerated to 800rpm, which corresponds to the rotating speed 2880rpm of the EM2 motor, and the motor is opened at the moment and cannot enter a weak magnetic state;

2. initial zero position assignment, namely taking an average value of motor angle values of the first 50 sets of assembly boxes as an initial angle;

3. reading an initial zero offset torque Ts measured by a rack, giving an initial id= -50A, and calibrating the angle to be within a range of +/-1 Nm of the initial zero offset torque;

4. when the calibration current increases to greater than the maximum weak current 300A, the angular calibration is completed.

In this embodiment, for the given idle speed of the hybrid transmission in step (1), the operation of performing the initial angle assignment θ includes:

the angle learning procedure of the step (1-1) is started;

step (1-2), the state request of the whole machine controller is in a standby state; the corresponding signals are: hbu_stmodereq=standby;

step (1-3) the device load side rotational speed request is increased to 800rpm (TBD) and the device input side rotational speed request is 0rpm (TBD); the corresponding signals are: spdreq_output_mot=800 rpm (TBD) & spdreq_input_mot=0 rpm;

step (1-4) HBU judges 10 frames continuously, confirms whether the rotation speed of the motor to be tested is equal to 2880rpm + -60 rpm (TBD); the corresponding signals are: motorncurr=2880±60rpm (TBD);

if yes, go to step (1-5); if not, returning to the step (1-3);

step (1-5), the state of the whole vehicle controller requests calibration, and after 500ms (TBD) delay, the torque of the load end of the equipment is calibrated; the corresponding signals are: hbu_stmodereq=calibre; PEU mode=calibre.

After the step (1) is completed, the step (2) is started after a delay of 500ms (TBD);

step (2) reading zero offset torque Ts of the motor at the idle rotation speed through the PEU; the corresponding signals are: PEU reads PC: trq_output_mot and denoted as Ts;

to facilitate understanding of the signal symbols in this embodiment, the description of each signal symbol is as follows:

hbu_stmodereq: vehicle controller status request

Spdreq_output_mot: device load side speed request

Spdreq_input_mot: device input end rotation speed request motor_Ncurr measured Motor rotation speed

PEU Mode: motor controller working mode

Trq_output_mot: load side torque of equipment

Angle_cali_fixed: angle calibration completion state

actl_angle: motor angle.

Step (3), giving the direct-axis current id of the motor to be tested through the PEU; the corresponding signals are: adjusting PEU output id= -50A;

step (4) reading real-time torque Tr of a motor through a PEU, and comparing the real-time torque Tr with the zero offset torque Ts in the step (2) to obtain a torque difference DeltaT; judging whether the delta T is less than or equal to 1.5Nm (TBD), if not, adjusting the zero angle of the motor; if yes, go to step (5);

wherein Δt=tr-Ts;

an operation for adjusting a zero angle of a motor comprising:

step (4-1) confirms whether DeltaT is more than or equal to 0, if so, entering step (4-2); if not, entering the step (4-3);

step (4-2) confirms whether DeltaT is more than or equal to 10Nm (TBD), if so, the zero angle of the adjusting motor is increased by 0.32 degrees; if not, the zero angle of the adjusting motor is increased by 0.05 degrees; after the completion, the step (4-4) is carried out;

step (4-3) confirms whether DeltaT is less than or equal to minus 10Nm (TBD), if so, the zero angle of the adjusting motor is reduced by 0.32 degrees; if not, the zero angle of the adjusting motor is reduced by 0.05 degrees; after the completion, the step (4-4) is carried out;

step (4-4) reads the current motor real-time torque Tr through the PEU, confirms whether the delta T is smaller than or equal to 1.5Nm (TBD), and if so, enters step (4); if not, return to step (4-1)

Step (5), increasing the direct axis current id of the motor to be tested to-300A (TBD) through the PEU, judging whether the direct axis current id of the motor to be tested is smaller than or equal to-300A (TBD), and returning to step (4) if not; if yes, the calibration is completed.

The above description is for the purpose of illustrating the embodiments of the present invention and is not to be construed as limiting the invention, but is intended to cover all modifications, equivalents, improvements and alternatives falling within the spirit and principle of the invention.

Claims (6)

1. The zero angle calibration method for the power splitting hybrid gearbox offline motor is characterized by comprising the following steps of:

step (1) giving the idle load rotating speed of the hybrid gearbox, and carrying out initial angle assignment theta;

step (2) reading zero offset torque Ts of the motor at the idle rotation speed through the PEU;

step (3), giving the direct-axis current id of the motor to be tested through the PEU;

step (4) reading real-time torque Tr of a motor through a PEU, and comparing the real-time torque Tr with the zero offset torque Ts in the step (2) to obtain a torque difference DeltaT; judging whether the delta T is smaller than or equal to a torque set value, if not, adjusting the zero angle of the motor; if yes, go to step (5);

step (5) increasing the direct-axis current id of the motor to be tested to a current set value through the PEU, judging whether the current direct-axis current id of the motor to be tested is smaller than or equal to the current set value, and returning to the step (4) if not; if yes, the calibration is completed.

2. The method for calibrating the zero angle of the power splitting hybrid transmission off-line motor according to claim 1, wherein in the step (4), a delay of 200ms (TBD) is required between the obtained torque difference Δt and the determination of Δt is less than or equal to a torque set point.

3. A method of calibrating zero angle of a power splitting hybrid transmission off-line motor according to claim 1 or 2, wherein the torque set point is 1.5Nm (TBD).

4. The method for calibrating the zero angle of the power splitting hybrid gearbox off-line motor according to claim 1, wherein in the step (5), whether the current measured motor direct axis current id is smaller than or equal to a current set value is judged, and a time delay of 200ms is required between the step (4) and the step (4).

5. A method of zero angle calibration of a power splitting hybrid transmission off-line motor as defined in claim 1 or 4, wherein the current set point is-300A (TBD).

6. The method for calibrating the zero angle of the power splitting hybrid transmission offline motor according to claim 1, wherein the adjusting the zero angle of the motor in the step (4) specifically comprises:

step (4-1) confirms whether DeltaT is more than or equal to 0, if so, entering step (4-2); if not, entering the step (4-3);

step (4-2) confirms whether DeltaT is more than or equal to 10Nm (TBD), if so, the zero angle of the adjusting motor is increased by 0.32 degrees; if not, the zero angle of the adjusting motor is increased by 0.05 degrees; after the completion, the step (4-4) is carried out;

step (4-3) confirms whether DeltaT is less than or equal to minus 10Nm (TBD), if so, the zero angle of the adjusting motor is reduced by 0.32 degrees; if not, the zero angle of the adjusting motor is reduced by 0.05 degrees; after the completion, the step (4-4) is carried out;

step (4-4) reads the current motor real-time torque Tr through the PEU, confirms whether the delta T is smaller than or equal to a torque set value, and if yes, enters step (4); if not, returning to the step (4-1).