KR101093517B1 - Motor Position Initial Angle Offset Correction Method - Google Patents

Abstract

The present invention relates to a motor position initial angle offset correction method for an electric vehicle, and more particularly, when the initial angle offset (Offset) of the initial position of the rotor of the motor is generated by the mounting environment of the motor position and the speed sensor, An electric vehicle motor position initial angle offset correction method for correcting this initial angle offset is provided.

That is, the present invention may cause the deformation of the sensing information according to the process and environment in which the position and speed sensors mounted on the motor shaft of the engine room are mounted on the inverter system, and the control due to an error due to the absolute angle movement of the rotor. In order to solve the problem of deterioration of performance, the initial angle offset of the initial position of the rotor of the motor is generated by the motor position and the speed sensor mounting environment. An object of the present invention is to provide an electric vehicle motor position initial angle offset correction method for correcting an initial angle offset through a control algorithm of a controller.

Electric vehicle, motor, position and speed sensor, deformation, offset, correction, initial angle

Description

Motor position initial angle offset correction method for electric vehicles {Method for compensation motor position offset of HEV}

The present invention relates to a motor position initial angle offset correction method for an electric vehicle, and more specifically, the initial angle offset (Offset) of the initial position of the rotor of the motor will be generated by the mounting environment of the motor position and speed sensor. In this case, the present invention relates to a motor position initial angle offset correction method for correcting the initial angle offset.

The vector control technique used in the industrial inverter system where high performance and high efficiency is required is used for motor control of hybrid electric vehicle or fuel cell electric vehicle.

The vector control is a technique for controlling the AC motor to improve the performance of the DC motor and at the same time improved.

2 shows a structure in which a general controller and an inverter for high performance vector control are connected between a motor and a battery.

As shown in FIG. 2, an inverter 16 is connected between the motor 10 and the battery 12, and a current sensor 18 is positioned in the connection line between the motor 10 and the inverter 16. The position and speed sensors 20 mounted on the rotor side of the 10 are connected to the controller 14 of the inverter 16.

For the vector control of the motor 10, the position of the rotor magnetic flux of the motor needs to be known, and a widely used method is to attach the position and speed sensor 20 to the rotor to determine the absolute or relative position of the rotor. There is a way.

In general, a rotary transducer such as a resolver or a rotary encoder is used as a sensor for detecting the position and speed of the rotor.

The rotary encoder has an absolute encoder and an incremental encoder, and the resolver and the absolute encoder have the advantage of always detecting the absolute position of the rotor, but are not widely used due to the high price. There is this.

The controller 14 of the inverter 16 uses a position and speed sensor 20 (encoder or resolver) for high performance vector control of the motor, as shown in the controller structure of the inverter system of FIG. The rotor position θ _r of the motor for the control algorithm is calculated.

In addition, when a position control or speed control algorithm is required according to the structure of the controller 14, the measured position θ _r and velocity (ω _rpm ) values are required.

In the case of hybrid electric vehicles or fuel cell electric vehicles, in the inverter system for high performance control, the motor is located in the engine room of the car instead of the internal combustion engine, and the position and speed sensors (encoder and resolver) are located on the rear axle of the motor. It is integrally mounted to feed back the sensing (θ _r ) information to the controller for stable control.

However, since the encoder mounted on the motor shaft of the engine room, that is, the position and speed sensor, is susceptible to damage from mechanical shock, its reliability may be deteriorated depending on the environment of the inverter system, and thus sensing (θ _r ) information. There may be a problem that deformation may occur, and eventually an error may occur in calculating a position and velocity for high performance vector control.

In addition, due to an error due to the movement of the absolute angle that may occur in the process of mounting the position and speed sensor to the inverter system, there is a problem that the control performance is reduced.

As such, in order for the motor driving system to have control reliability, it may be important to sense the deformation (offset, etc.) of the position θ _r or the speed ω _rpm which are important signals.

Various methods for detecting the deformation (hereinafter referred to as offset) have been studied, and as one of the conventional methods, an error occurs by comparing a reference value with an actual value of a motor in a general feedback control system. In this case, a method of performing a control for correcting the error amount is mainly used.

In the case of such a general feedback control system, a problem arises in determining an error value due to the occurrence of an overshoot of a step response of an actual system.

Another conventional method is to compare the output value of the model with the actual motor output based on modeling. This modeling comparison method sets an error range according to a problem such as the parameter of the motor or the saturation of the integrator of the controller. There is a disadvantage that a problem occurs.

In addition, although a technique of determining an error range by designing an estimator (Observer) through an advanced control theory among the conventional control methods has been used, there is a disadvantage that the control execution time of the controller is long because the actual controller implementation is complicated.

According to the present invention, deformation of sensing information may occur according to a process and environment in which a position sensor and a speed sensor mounted on a motor shaft of an engine room are mounted on an inverter system. In order to solve the problem of deterioration, the controller detects the offset and corrects the position signal when the initial angle offset of the initial position of the rotor is generated by the motor position and the speed sensor mounting environment. An object of the present invention is to provide a method for correcting an initial angle offset of a motor position for an electric vehicle, which can correct the initial angle offset through a control algorithm of.

,

)을 통해 상기 제어기에서 각오차(θ_err)를 계산하고, 상기 각오차(θ_err)를 반영한 보정된 회전자의 위치(θ_{r_comp})값이 제어기에 적용되는 단계와; 상기 각오차(θ_err)를 반영한 전류제어기의 출력전압(

,

)으로부터 변환된 출력상전압(

,

,

)이 인버터에 인가되어 원하는 토크로 상기 전동기를 구동하는 단계; 로 이루어지는 것을 특징으로 하는 전기자동차용 모터 위치 초기각 오프셋 보정 방법을 제공한다.The present invention for achieving the above object comprises the steps of sensing the position (θ _r ) and the speed (ω _r ) of the rotor in the position and speed sensor of the motor, respectively; Sensing a three-phase current (i _as , i _bs , i _cs ) in a current sensor and converting the three-phase current into a dq-axis current (i _ds , i _qs ) for vector control; Detecting, by the controller, an offset of an output value by an integral controller of the proportional integral controller obtained by using the position, the speed, and the dq-axis current of the rotor; The amount of offset detected (

,

) It was prepared to calculate the difference (θ _err) in the controller, and the phase difference determination (θ _err) reflects the position (θ _{r_comp)} value of the corrected rotor is applied to a controller through; The output voltage of the current controller reflecting the angle _error (θ _err )

,

Output phase voltage converted from

,

,

) Is applied to the inverter to drive the motor to the desired torque; It provides an electric vehicle motor position initial angle offset correction method, characterized in that consisting of.

Through the above problem solving means, the present invention provides the following effects.

According to the present invention, a deformation of the sensing information may occur according to a process and an environment in which the position and speed sensor are mounted in the inverter system. That is, the initial angle offset of the initial position of the rotor of the motor position and the speed sensor may be changed. If this occurs, it is possible to correct the position signal by detecting the offset.

In this way, it is possible to prevent the performance degradation of the surface-mounted permanent magnet synchronous motor by detecting the rotor position and the speed sensor offset of the motor, thereby improving the reliability of hybrid electric vehicles and fuel cell electric vehicles. .

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

An object of the present invention is to propose an algorithm for detecting an offset of a new position and speed sensor in a surface-mounted permanent magnet synchronous motor drive system.

)의 각 오차(θ_err)로 인한 오프셋이 발생할 경우, 이 오프셋을 감지 하여 보정하는 방법을 제공하고자 한 것이다.That is, the present invention is surface-mounted permanent magnet synchronous motor drive system, normally a mounting position of a position and speed sensor bakkwieoseo by internal or external factors, the actual operating angle (θ _r) and the control angle (

In the case where an offset due to each error θ _err occurs, it is intended to provide a method of detecting and correcting the offset.

The surface-mounted permanent magnet synchronous motor is modeled as in Equation 1 below, and its torque can be obtained from Equation 2.

및

는 각각 동기 좌표계 상에서 고정자측 d축 및 q축 전압이고,

및

는 d축 및 q축 전류, ω_r은 회전자 속도, r_s는 저항, L_s는 실제 인덕턴스, K_e는 역기전력 상수 그리고 p는 시간에 대한 미분연산자 즉,

를 각각 나타낸다.In Equation 1,

And

Are the d-axis and q-axis voltages of the stator on the synchronous coordinate system, respectively.

And

Is the d-axis and q-axis current, ω _r is the rotor speed, r _s is the resistance, L _s is the actual inductance, K _e is the counter electromotive force constant, and p is the differential operator for time,

Respectively.

)에 의하여 발생된다.Torque of the surface-mounted permanent magnet synchronous motor (T _e ) is the number of poles of the motor (P), the back EMF constant (λ _f = K _e ) and the q-axis current (

Is generated by

In general, the surface-mounted permanent magnet synchronous motor controls the torque by controlling the d-axis current to 0 to obtain the maximum torque, which is controlled by a negative current value to reduce the counter electromotive force at high speed.

3 is a controller of an inverter system using a position and speed sensor of an electric motor, and the voltage equation of the current controller based on the controller is expressed by Equations 3 and 4 below.

는 d축,q축 전류 제어기의 비례적분제어 출력전압값,

는 d축,q축 전류 오차,

는 d축,q축 비례적분제어기의 비례(P) 게인,

는 d축,q축 비례적분제어기의 적분(I)게인,

는 시간에 대한 미분연산자 즉,

를 각각 나타낸다. 즉, 도 2 및 도 3의 제어기(14) 내에 전류제어기가 있고, 이 전류제어기 내에 비례적분(PI)제어기가 배치된다. 또한 전류제어기 대역폭(Bandwidth)을 넓게 하기 위하여 수학식 4에서와 같은 전향보상(Feedforward) 전압(

,

)을 더하게 된다. 여기서,

는 추정 혹은 측정된 인덕턴스 값을 의미한다.As shown in Figure 3, the current controller is configured as a proportional integral controller (Proportional & Integral Control). In equation (3)

Is the proportional integral control output voltage value of d-axis, q-axis current controller,

Is the d-axis and q-axis current error,

Is the proportional gain of d-axis and q-axis proportional integral controller,

Is the integral (I) gain of d-axis and q-axis proportional integral controller,

Is the derivative of time,

Respectively. That is, there is a current controller in the controller 14 of Figs. 2 and 3, and a proportional integral (PI) controller is arranged in this current controller. In addition, in order to widen the bandwidth of the current controller, the forward compensation voltage (

,

) Is added. here,

Is the estimated or measured inductance value.

Based on the above Equations 3 and 4, the output voltage of the current controller is expressed as Equation 5.

,

)를 이용하여 얻은 비례적분제어 출력전압에 전향보상 전압을 더하여 얻는다. 상기 전류제어기의 출력전압(

)으로부터 변환된 출력상전압(

,

,

)이 인버터에 인가되고, 인버터의 스위치 동작을 결정하여 표면 부착형 영구자석 동기 전동기가 구동된다.That is, the output voltage of the current controller is the position (θ _r ) and speed (ω _r ) of the rotor sensed by the position sensor and the speed sensor of the motor, dq axis current (

,

It is obtained by adding the forward compensation voltage to the proportional integral control output voltage obtained using Output voltage of the current controller (

Output phase voltage converted from

,

,

Is applied to the inverter, and the switch operation of the inverter is determined to drive the surface-mounted permanent magnet synchronous motor.

When the positional information fed back to the current controller changes the mounting position of the encoder, an error is generated as shown in Equation 6 below, and thus the controller is set at an angle error θ _err as shown in Equation 7 below. As a result of the control, the control values of the current controller are changed to compensate for the voltage and current generated by the angular error in the motor.

수학식 6에서 θ_r 는 취부 위치가 바뀌기 전 회전자의 위치,

은 취부 위치가 바뀐 후 회전자의 위치를 나타내고, 수학식 7에서

,

는 각오차(θ_err)에 의하여 발생한

기준의 d축 및 q축 전압값,

,

는 각오차(θ_err)에 의하여 발생한

기준의 d축 및 q축 전류값, ω_r은 회전자 속도, r_s는 저항, L_s는 인덕턴스, K_e는 역기전력 상수를 각각 나타낸다.

Θ _r in Equation 6 The position of the rotor before the mounting position changes,

Represents the position of the rotor after the mounting position is changed,

,

Is caused by the _{angular error} (θ _err )

D-axis and q-axis voltage values of the reference,

,

Is caused by the _{angular error} (θ _err )

The reference d- and q-axis current values, ω _r are the rotor speed, r _s is the resistance, L _s is the inductance, and K _e is the counter electromotive force constant.

That is, the integrator of the current controller reflects the voltage value due to the _{angular error} (θ _err ) as shown in Equations 8 and 9 below, and the offset of the position and speed sensor (encoder or resolver) is used by using the voltage value. Offset) can be detected.

,

는 각오차(θ_err)가 반영된 비례적분제어기 중 적분제어기에 의해 연산되는 d,q 축 전압값을 각각 나타낸다. here

,

_Denotes the d, q-axis voltage values calculated by the integral controller among the proportional integral controllers in which the _{angular error} (θ _err ) is reflected.

이다.When the angle _error θ _err of Equations 8 and 9 is a small value,

to be.

따라서, 위 수학식 10에 의거, 되먹임(Feedback)된 전압값을 이용하는 알고리즘으로 위치 및 속도센서의 취부 위치가 바뀌어서 실제각(θ_r)과 제어각(

)의 각오차(θ_err)로 인한 오프셋이 발생할 경우, 이 오프셋(Offset)을 보정하는 방법은 첨부한 도 1처럼 진행되어진다.

Therefore, according to Equation 10 above, the position and the mounting position of the speed sensor are changed by the algorithm using the fed back voltage value, so that the actual angle (θ _r ) and the control angle (

If an offset due to the _{angular error} θ _err occurs, the method of correcting the offset proceeds as shown in FIG. 1.

1 is a flowchart illustrating a method of correcting an initial angle offset of a motor position for an electric vehicle according to the present invention.

First, the position (θ _r ) and the speed ω _r of the rotor of the surface-mounted permanent magnet motor are sensed by the position and speed sensor (S101).

Next, the current sensor senses three-phase current (i _as , i _bs , i _cs ) (S102), and converts the sensed three-phase current into dq-axis current (i _ds , i _qs ) for vector control (Conversion) (S103).

Subsequently, the current control of the current controller for following the torque command is carried out using the position and speed of the rotor and the dq-axis current, and by monitoring the output value of the integral controller among the proportional integral controllers in the current controller, the position and Detect the deformation or offset of the speed sensor (S104). That is, when there is an offset of the position and velocity sensor, an offset of the output value of the integral controller eventually occurs due to the angular error and is detected by the controller.

More specifically, the positional information fed back to the current controller generates an _{angular error} θ _err as shown in Equation 6 above when the mounting position of the encoder is changed, whereby the controller generates the above equation. As shown in Fig. 7, the motor is controlled by the _{angular error} θ _err . At this time, if the angular _error θ _err is a small value, the angular _error θ _err may be controlled by the motor as shown in Equation 10 above.

,

)을 통해 각오차(θ_err)를 계산하는 단계(S105) 및 각오차(θ_err)를 반영한 보정된 회전자 위치(θ_{r_comp})값을 구하는 단계를 수행하게 된다 (S106). When the inverter controller detects a failure or offset of the position and speed sensor, the detected offset amount (

,

) The prepared difference (θ _err) to thereby perform a step (S105) and the determination order (θ _err), the time step to obtain the value of rotor position (θ _{r_comp)} reflects the correction calculating (S106) through.

,

)으로부터 도 3의 T(θ^-1)를 이용하여 변환된 출력상전압(

,

,

)이 인버터에 인가된다 (S107, S108). 이를 통해 원하는 토크로 전동기를 정확하게 제어할 수 있으며, 성능 저하를 막을 수 있을 뿐만 아니라 본 전동기가 적용되는 전기자동차의 신뢰성도 향상시킬 수 있게 된다.Accordingly, the output voltage of the current controller (with the corrected rotor position θ _{r_comp} ) applied to the controller.

,

Output phase voltage converted from T (θ- ¹ ) of FIG.

,

,

) Is applied to the inverter (S107, S108). Through this, it is possible to precisely control the motor with the desired torque, to prevent performance degradation and to improve the reliability of the electric vehicle to which the motor is applied.

1 is a flowchart illustrating a method for correcting an initial angle offset of a motor position for an electric vehicle according to the present invention;

2 is a structural diagram of a general controller and inverter connected between a motor and a battery for high performance vector control;

3 is a control diagram of a controller of an inverter system using a position and speed sensor of an electric motor.

<Explanation of symbols for the main parts of the drawings>

10: motor

12: battery

14: controller

16: inverter

18: current sensor

20: position and speed sensor

Claims (3)

Sensing the position θ _r and the speed ω _r of the rotor in the position and speed sensors of the motor, respectively; Sensing a three-phase current (i _as , i _bs , i _cs ) in a current sensor and converting the three-phase current into a dq-axis current (i _ds , i _qs ) for vector control; Detecting, by the controller, an offset of an integral controller output value among proportional integral controllers obtained by using the position, the speed, and the d-q axis current of the rotor; The amount of offset detected (

,

) It was prepared to calculate the difference (θ _err) in the controller, and the phase difference determination (θ _err) reflects the position (θ _{r_comp)} value of the corrected rotor is applied to a controller through; The output voltage of the current controller reflecting the angle _error (θ _err )

,

Output phase voltage converted from

,

,

) Is applied to the inverter to drive the motor to the desired torque; Motor position initial angle offset correction method characterized in that consisting of. The method of claim 1, wherein the motor control reflecting the _{angular error} (θ _err ) is

Motor position initial angle offset correction method, characterized in that made by. here,

,

Is caused by the _{angular error} (θ _err )

D-axis and q-axis voltage values of the reference,

,

Is caused by the _{angular error} (θ _err )

Reference d- and q-axis current values, ω _r is the rotor speed, r _s is the resistance, L _s is the inductance, and K _e is the counter electromotive force constant. The method of claim 2, wherein the angle _error (θ _err ) value is

Motor position initial angle offset correction method characterized in that the electric motor control is calculated by. here,

Is the d-axis voltage value calculated by the integral controller among the proportional integral controllers reflecting the _{angular error} (θ _err ).

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