motor control method and device based on rotary change initial position
阅读说明：本技术 一种基于旋变初始位置的电机控制方法及装置 (motor control method and device based on rotary change initial position ) 是由 刘帅 张广利 纪秉男 于 2018-07-18 设计创作，主要内容包括：本发明涉及新能源汽车电机控制领域,具体涉及一种基于旋变初始位置的电机控制方法及装置。本发明通过增加一个补偿的环节,在补偿环节中通过检测电机状态参数计算旋变初始位置,根据旋变初始位置计算电机目标值的补偿值并进行叠加,从而对电机进行控制。本发明通过多次检测并判断是否在设定范围,从而丢弃不符合条件的检测结果,然后根据多个检测结果计算旋变初始位置,能够更好地反应电机的运行情况。本发明避免了在高速零转矩工况下,由于旋变初始位置偏差,电机处于发电工况,导致电机控制器过压。(The invention relates to the field of motor control of new energy automobiles, in particular to motor control methods and devices based on a rotary change initial position, wherein compensation links are added, the rotary change initial position is calculated by detecting motor state parameters in the compensation links, and a compensation value of a motor target value is calculated according to the rotary change initial position and is superposed, so that the motor is controlled.)
1, A motor control method based on rotary change initial position, characterized by comprising the following steps:
when the motor works under a set working condition, detecting the running state parameters of the motor;
calculating a rotation change initial position according to the operation state parameters;
calculating a compensation value by using the calculated initial position of the rotation change,
and superposing the target value, the feedback value and the compensation value to form a control instruction, and controlling the motor to operate.
2. The motor control method based on rotation change initial position, wherein the set condition includes that the required torque of the motor is zero and the rotation speed of the motor is greater than the set high speed threshold.
3. A motor control method based on rotation change initial position, according to claim 1 or 2, wherein the process of calculating the rotation change initial position includes:
times of rotation change initial position detection is carried out in each sampling period, whether the detection result is effective or not is judged after each detection, if yes, the detection result is recorded, if the detection result is in a set range, the detection result is judged to be effective, otherwise, the detection result is invalid;
and judging whether the preset detection times are finished or not, and if the detection times are finished and at least detection results are recorded, calculating to obtain the initial position of the rotary transformer according to the recorded detection results.
4. The motor control method based on rotation-change initial position as claimed in claim 3, wherein the operation state parameters include field weakening voltage and excitation voltage, and the rotation-change initial position is calculated according to the field weakening voltage and the excitation voltage:
wherein gamma is the initial position of the rotary transformer, and the unit is radian; uq is the excitation voltage, and Ud is the field weakening voltage.
5. The motor control method based on rotation change initial position, wherein the compensation value includes excitation compensation current and weak magnetic compensation current, the target excitation current and weak magnetic current are adjusted according to the excitation compensation current and weak magnetic compensation current;
the excitation compensation current and the field weakening compensation current are respectively as follows:
Iqr＝Iq*sinγ
Idr＝(1-cosγ)*Id
wherein Iqr is the excitation compensation current, Idr is the field weakening compensation current, γ is the rotational transformation initial position, Iq is the target excitation current, and Id is the target field weakening current.
The motor control device based on the rotary change initial position is 6, , and comprises a processor and a memory, wherein the memory stores instructions of the processor for realizing the following method:
when the motor works under a set working condition, detecting the running state parameters of the motor;
calculating a rotation change initial position according to the operation state parameters;
calculating a compensation value by using the calculated initial position of the rotation change,
and superposing the target value, the feedback value and the compensation value to form a control instruction, and controlling the motor to operate.
7. The motor control device based on rotation change initial position, wherein the set condition includes that the required torque of the motor is zero and the rotation speed of the motor is greater than the set high speed threshold.
8. type motor control device based on rotation change initial position, according to claim 6 or 7, wherein the process of calculating the rotation change initial position includes:
times of rotation change initial position detection is carried out in each sampling period, whether the detection result is effective or not is judged after each detection, if yes, the detection result is recorded, if the detection result is in a set range, the detection result is judged to be effective, otherwise, the detection result is invalid;
and judging whether the preset detection times are finished or not, and if the detection times are finished and at least detection results are recorded, calculating to obtain the initial position of the rotary transformer according to the recorded detection results.
9. The motor control device based on rotation initial position, as claimed in claim 8, wherein the operating condition parameters include field weakening voltage and excitation voltage, and the rotation initial position is calculated from the field weakening voltage and the excitation voltage:
wherein gamma is the initial position of the rotary transformer, and the unit is radian; uq is the excitation voltage, and Ud is the field weakening voltage.
10. The motor control device based on rotation initial position of claim 9, wherein the compensation value includes excitation compensation current and field weakening compensation current, the target excitation current and the target field weakening current are adjusted according to the excitation compensation current and the field weakening compensation current respectively;
the excitation compensation current and the field weakening compensation current are respectively as follows:
Iqr＝Iq*sinγ
Idr＝(1-cosγ)*Id
wherein Iqr is the excitation compensation current, Idr is the field weakening compensation current, γ is the rotational transformation initial position, Iq is the target excitation current, and Id is the target field weakening current.
Technical Field
The invention relates to the field of motor control, in particular to motor control methods and devices based on a rotary change initial position.
Background
With the increasing exhaustion of traditional energy sources such as petroleum and coal and the continuous aggravation of environmental pollution, new energy automobiles become a necessary trend for the development of the automobile industry. The motor system is a core component of the new energy automobile, and has the main functions of controlling the driving motor to work, providing power for the automobile, providing an auxiliary braking function when the automobile is braked and recycling braking energy. Therefore, the working state of the motor system directly influences the power output of the whole vehicle and the driving safety of the new energy vehicle. The initial position of the rotary transformer is used as a base point of motor control, and plays a decisive role in the accuracy of motor torque control. The deviation of the initial position of the rotary transformer can cause the output torque of a motor system to be smaller or the current control to be disordered, thereby causing the power interruption of the whole vehicle.
The motor factory detection method is that a motor manufacturer marks the rotational change initial position of a motor on a motor nameplate when the motor leaves a factory, the rotational change initial position is provided for a controller manufacturer to carry out control program determination when the motor is installed on a whole vehicle, the rotating speed of the motor is dragged to fixed values after the whole vehicle is installed, and the detected values are written into a motor control program.
After the initial position of the rotary transformer detected by the two methods is written into a control program, the initial position of the rotary transformer cannot be changed, and the error of the initial position of the rotary transformer caused by human errors in the detection process of the initial position of the rotary transformer cannot be avoided, so that the output torque of a motor system is smaller or the power of the whole vehicle is interrupted due to current control disorder. Under the high-speed zero-torque working condition, the motor is in the power generation working condition due to the rotational change initial position deviation, so that the motor controller is in overvoltage.
Disclosure of Invention
The invention aims to provide motor control methods and devices based on a rotary transformer initial position, which are used for solving the problem that a motor controller is easy to break down when the rotary transformer initial position has deviation.
In order to achieve the above object, the present invention provides motor control methods based on a rotation initial position, comprising the following steps:
when the motor works under a set working condition, detecting the running state parameters of the motor;
calculating a rotation change initial position according to the operation state parameters;
calculating a compensation value by using the calculated initial position of the rotation change,
and superposing the target value, the feedback value and the compensation value to form a control instruction, and controlling the motor to operate.
, the set condition includes that the required torque of the motor is zero and the rotation speed of the motor is greater than the set high speed threshold.
At step , the process of calculating the rotational initial position includes:
times of rotation change initial position detection is carried out in each sampling period, whether the detection result is effective or not is judged after each detection, if yes, the detection result is recorded, if the detection result is in a set range, the detection result is judged to be effective, otherwise, the detection result is invalid;
and judging whether the preset detection times are finished or not, and if the detection times are finished and at least detection results are recorded, calculating to obtain the initial position of the rotary transformer according to the recorded detection results.
, the operation state parameters include weak magnetic voltage and excitation voltage, and the rotation initial position is calculated according to the weak magnetic voltage and the excitation voltage:
wherein gamma is the initial position of the rotary transformer, and the unit is radian; uq is the excitation voltage, and Ud is the field weakening voltage.
, the compensation value includes excitation compensation current and field weakening compensation current, and the target excitation current and the target field weakening current are adjusted according to the excitation compensation current and the field weakening compensation current respectively;
the excitation compensation current and the field weakening compensation current are respectively as follows:
Iqr＝Iq*sinγ
Idr＝(1-cosγ)*Id
wherein Iqr is the excitation compensation current, Idr is the field weakening compensation current, γ is the rotational transformation initial position, Iq is the target excitation current, and Id is the target field weakening current.
The invention also provides motor control devices based on the rotary change initial position, which comprises a processor and a memory, wherein the memory stores instructions for the processor to realize the following method:
when the motor works under a set working condition, detecting the running state parameters of the motor;
calculating a rotation change initial position according to the operation state parameters;
calculating a compensation value by using the calculated initial position of the rotation change,
and superposing the target value, the feedback value and the compensation value to form a control instruction, and controlling the motor to operate.
, the set condition includes that the required torque of the motor is zero and the rotation speed of the motor is greater than the set high speed threshold.
At step , the process of calculating the rotational initial position includes:
times of rotation change initial position detection is carried out in each sampling period, whether the detection result is effective or not is judged after each detection, if yes, the detection result is recorded, if the detection result is in a set range, the detection result is judged to be effective, otherwise, the detection result is invalid;
and judging whether the preset detection times are finished or not, and if the detection times are finished and at least detection results are recorded, calculating to obtain the initial position of the rotary transformer according to the recorded detection results.
, the operation state parameters include weak magnetic voltage and excitation voltage, and the rotation initial position is calculated according to the weak magnetic voltage and the excitation voltage:
wherein gamma is the initial position of the rotary transformer, and the unit is radian; uq is the excitation voltage, and Ud is the field weakening voltage.
, the compensation value includes excitation compensation current and field weakening compensation current, and the target excitation current and the target field weakening current are adjusted according to the excitation compensation current and the field weakening compensation current respectively;
the excitation compensation current and the field weakening compensation current are respectively as follows:
Iqr＝Iq*sinγ
Idr＝(1-cosγ)*Id
wherein Iqr is the excitation compensation current, Idr is the field weakening compensation current, γ is the rotational transformation initial position, Iq is the target excitation current, and Id is the target field weakening current.
The invention has the advantages that compensation links are added, the initial position of the rotary transformer is calculated by detecting the state parameters of the motor in the compensation links, the compensation value of the target value of the motor is calculated according to the initial position of the rotary transformer and is superposed, so that the motor is controlled, and the overvoltage of a motor controller caused by the fact that the motor is in a power generation working condition due to the deviation of the initial position of the rotary transformer under the high-speed zero-torque working condition is avoided.
Meanwhile, whether the motor is in the set range or not is detected and judged for multiple times, so that the detection results which do not meet the conditions are discarded, and then the rotation initial position is calculated according to the detection results, and the running condition of the motor can be better reflected. The method obtains the initial position of the rotary transformer by obtaining the weak magnetic voltage and the excitation voltage, and has simple calculation and easy realization;
meanwhile, the weak magnetic compensation current and the excitation compensation current are calculated according to the calculated initial position of the rotary transformer, so that the target weak magnetic current and the target excitation current are adjusted.
Drawings
FIG. 1 is a voltage vector control schematic of a prior art motor controller;
FIG. 2 is a voltage vector control schematic of the motor controller of the present invention;
FIG. 3 is a flow chart of the method of the present invention;
fig. 4 is a flow chart of an embodiment of the present invention.
Detailed Description
The present invention is further described in detail below with reference to the attached figures.
At present, a motor controller basically adopts voltage vector control, and the voltage vector control principle is as shown in fig. 1 and includes:
1. the required torque Tq of the whole vehicle is obtained through a motor current table look-up module to obtain a target weak magnetic current Id and a target exciting current Iq;
2. the current conversion module obtains actual weak magnetic current Idf and actual exciting current Iqf fed back by the motor through coordinate conversion by utilizing the collected three-phase currents Ia, Ib and Ic of the motor and the rotation position signal theta;
3. the target weak magnetic current Id and the actual weak magnetic current Idf are regulated through PID to obtain weak magnetic voltage Ud; the target exciting current Iq and the actual exciting current Iqf are regulated by PID to obtain an exciting voltage Uq;
4. and the excitation voltage Uq and the weak magnetic voltage Ud are combined with a rotation position signal theta to obtain the three-phase voltage of the control motor through voltage vector control, so that the motor is controlled to operate.
The invention provides motor control methods and devices based on a rotary transformer initial position, aiming at the problem of rotary transformer initial position deviation after the detection of the rotary transformer initial position is completed.
As shown in FIG. 2, the motor voltage vector control diagram of the present invention can be obtained by combining the flowchart of FIG. 3. the method of the present invention includes that in the operation process of the whole vehicle, when the rotating speed of the motor is in a specific rotating speed range and the torque required by the whole vehicle to the motor is 0, the motor controller maintains a time zero torque output state.
specific embodiments are given below, and it should be noted that in this embodiment, the electric machine is in the high-speed zero-torque condition, but the operating condition of the electric machine is not limited to the above-mentioned high-speed zero-torque condition, and the method of the present invention is also applicable in other operating conditions.
The specific steps of the method of this embodiment are shown in fig. 4, and include:
, the motor controller obtains the initial position gamma of the rotary transformer according to the vehicle demand torque Tq, the motor speed n, the weak magnetic voltage Ud and the excitation voltage Uq, when the vehicle demand torque is 0 and the motor speed is more than a certain specific value n0, the weak magnetic voltage Ud and the excitation voltage Uq. of the motor are collected at the moment, and the initial position gamma of the rotary transformer is obtained by trigonometric function calculation, and the formula is as follows:
it should be noted that other calculation formulas and methods exist in the prior art, and therefore, the method for calculating the initial position of the resolver is not limited to the method provided by the present invention, and any existing calculation methods may be adopted.
Secondly, judging whether the initial position gamma of the rotary change is in a limited range, wherein the formula is as follows:
γ1<γ<γ2 (2)
if the calculated rotary change initial position exceeds the limited range, the calculated rotary change initial position is abandoned, and if the calculated rotary change initial position is within the limited range, the calculated rotary change initial position is recorded; the limited range is obtained by analyzing the default rotary change initial position of the motor.
Thirdly, judging whether the calculation of the initial position of the rotary transformer reaches the set times, if not, continuously detecting the weak magnetic voltage and the excitation voltage and calculating the corresponding initial position of the rotary transformer; if the set times is reached, the recorded initial position values of the rotary transformer are averaged to obtain an
And fourthly, the motor controller obtains the excitation compensation current Iqr and the weak magnetic compensation current Idr according to the required torque Tq of the whole vehicle, the rotating speed n of the motor and the latest rotation transformation
Iqr＝Iq*sinγ0(3)
Idr＝(1-cosγ0)*Id (4)
wherein Iqr is excitation compensation current, Idr is weak magnetic compensation current, and gamma is0For the latest initial position of the rotary transformer, Iq is the exciting current, and Id is the weak magnetic current。
As can be obtained from fig. 2, the excitation compensation current and the field weakening compensation current are fed back to the output ends of the excitation current and the field weakening current, and act on the target excitation current and the target field weakening current together with the actual field weakening current Idf and the actual field weakening current Iqf fed back by the motor, and then the field weakening voltage and the excitation voltage are adjusted by PID control.
When the rotation initial position is calculated according to the weak magnetic voltage and the excitation voltage, the calculation can be carried out for multiple times according to the set frequency, or only times, when only times of calculation are carried out and the calculated rotation initial position is not in the set range, the calculation result obtained at this time is discarded, the subsequent calculation is carried out according to the default rotation initial position of the motor, if the calculation result is in the set range, the excitation compensation current and the weak magnetic compensation current are calculated according to the calculation result, and if the rotation initial position which is not reserved after the multiple times of calculation is not in the set range, the subsequent calculation is also carried out according to the default rotation initial position of the motor.
The above embodiments have been described with reference to the control method applied to the motor of the vehicle, and the essence of the present invention lies in the control of the motor, so that the method of the present invention can be applied to motors other than the motor of the vehicle as other embodiments.
Meanwhile, the invention is a research on motor current loop control, but for a person in the field, the method according to the invention can be easily changed into voltage loop control, so that the application of the method to motor current loop control also belongs to the protection scope of the invention.
The above embodiments of the present invention are provided, but the present invention is not limited to the described embodiments, for example, the selection of specific values in the method of the present invention, or the simple transformation of the calculation formula, and the technical solution formed by the above embodiments is formed by fine tuning, and still falls into the protection scope of the present invention.