KR20170045477A

KR20170045477A - Control device for wound field synchronous motor

Info

Publication number: KR20170045477A
Application number: KR1020150145066A
Authority: KR
Inventors: 손태식
Original assignee: 주식회사 만도
Priority date: 2015-10-19
Filing date: 2015-10-19
Publication date: 2017-04-27

Abstract

In a control apparatus of an inverter that receives DC power and converts DC power into the driving power of a field synchronous motor, a control device for a wound field synchronous motor according to an embodiment of the present invention includes a first sensor unit for measuring the voltage and the current of a DC terminal, a torque compensation unit for calculating a compensated torque command value based on an inputted torque command value and a current measured by the first sensor unit, and a field current compensation unit for calculating a voltage compensation value so as to reduce the voltage ripple and the current ripple of the DC terminal based on the current measured by the first sensor unit. So, the ripple of the DC power can be reduced.

Description

TECHNICAL FIELD [0001] The present invention relates to a control device for a field winding linear synchronous motor,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control apparatus for controlling a motor, and more particularly, to a control apparatus of an inverter for improving torque estimation performance using an electric output and reducing DC current and voltage ripple.

Unlike a permanent magnet synchronous motor (PMSM), a WRSM (Wound Field Synchronous Motor) is a structure in which a winding is included in a rotor, A rotor flux is generated by the current.

Therefore, in order to generate the torque in the field winding synchronous motor, the stator currnet and the rotor current (field current) must be controlled simultaneously.

In order to measure the torque in the motor drive system, a structure in which a separate sensor and a sensor can be mounted is required. Therefore, even in a system that performs torque control, the torque of the motor is generally estimated without using feedback of the actual torque.

Accordingly, in the prior art, an electric motor is used to estimate the torque of the electric motor. However, if the enacted number is incorrect, accurate estimation is impossible, and the tracking performance of the torque controller is also degraded.

The following prior art documents relate to a motor driver system and a control method in which even when the motor operates in the weak field region to reduce the commanded magnetic flux, the current, the q-axis current control, The technical features of the control unit are disclosed and the technical gist of the present invention is not included.

Korean Patent Publication No. 10-2007-0052796

A control device for a field winding type synchronous motor according to an embodiment of the present invention aims to solve the following problems.

First, an apparatus for reducing the ripple of a DC power supply is provided.

Second, an apparatus for improving the mechanical torque tracking performance is provided.

The present invention has been made in view of the above problems, and it is an object of the present invention to at least solve the problems in the conventional arts.

A control device for an in-line synchronous motor according to an embodiment of the present invention includes a sensor unit for measuring a voltage and a current of a DC terminal, A torque compensation unit for calculating a compensated torque command value based on the input torque command value and the current measured by the sensor unit, a voltage compensation value calculation unit for calculating a voltage compensation value so as to reduce the voltage ripple and current ripple of the DC stage based on the current measured by the sensor unit And a field current compensating unit.

The torque compensating unit includes an electric estimator for calculating a predicted electric output value based on the torque command value and the rotational angular velocity of the electric motor, an electric calculator for calculating an electric output value based on the measured current and voltage, And a controller for calculating a compensated torque command value.

The electric estimating section includes a torque estimating section for calculating an estimated torque value based on the torque command value and the rotational angular velocity of the electric motor, a data section for storing the efficiency table in which the motor efficiency is measured according to the torque command value and the rotational angular velocity of the electric motor, And a calculation unit for calculating an expected electrical output value based on the calculated electrical output value.

The field current compensating section includes a current change amount calculating section for calculating a current change amount of the DC stage and a voltage compensation calculating section for calculating a voltage compensation value based on the current change amount calculated by the current change amount calculating section.

The control apparatus for the field winding synchronous motor according to the embodiment of the present invention can calculate the voltage compensation value so as to compensate the field current by measuring the amount of change of the DC stage,

Further, since the input torque command value is compensated by using the electric output value in the torque compensating unit, the torque control follow-up performance can be improved.

The effects of the present invention are not limited to those mentioned above, and other effects not mentioned can be clearly understood by those skilled in the art from the following description.

1 is a block diagram showing a control apparatus for a field winding synchronous motor according to an embodiment of the present invention.
2 is a block diagram showing a torque compensating unit of a control apparatus for a field winding synchronous motor according to an embodiment of the present invention.
3 is a block diagram showing an electrical estimator of a control apparatus for a field winding synchronous motor according to an embodiment of the present invention.
4 is a block diagram showing a field current compensation unit of a control apparatus for a field winding synchronous motor according to an embodiment of the present invention.

The present invention will be described in detail with reference to the accompanying drawings. It is to be noted that the accompanying drawings are only for the understanding of the present invention and should not be construed as limiting the scope of the present invention.

First, the configuration of a control apparatus for controlling a field winding type motor will be described. When the torque command value is input, the PWM signal generating unit 7 or the Space Vector Modulating unit outputs the output signal to the PWM inverter 3 so that the torque is generated as commanded by the field winding type motor. At this time, the current command generator 4 determines the current commands Id * and Iq * If * to be the highest efficiency at the current operating point. Here, Id * is a magnetic flux generating current command which is a current on a two-phase synchronous coordinate system, Iq * is a torque generating current command which is a current on a two-phase synchronous coordinate system, and If * is a field current generating command of the electric motor.

The current controller 5 receives the currents Id *, Iq * and If * and performs current control calculations to generate voltage commands Vd *, Vq *, and Vf_control based on the current control operations. By performing the current control in this manner, it is possible to control the magnetic flux generating current, the torque generating current and the field current with high precision, thereby enabling the magnetic flux, torque, and field control of the electric motor.

The PWM converter 8 outputs an output signal based on Vf_control.

The three-phase converter 6 receives the voltages Vd * and Vq *, generates coordinate transformations on the U-V-W phase, and outputs AC voltage commands Va *, Vb * and Vc * of three phases.

Therefore, the PWM signal generating unit 7 converts the AC voltage command signals Va *, Vb *, and Vc * into PWM signals to be applied to the PWM inverter.

The motor currents Ia, Ib and Ic detected by the second sensor unit 12 are inputted to the dq converting unit 9 and the dq converting unit 9 detects the dq converting unit 9 based on the positional information detected by the position sensor 16 The current Iq and Id are fed back to the current control unit 5 and the motor field current If detected by the third sensor unit 14 is fed back to the current control unit 5. [

This method is a control method generally called vector control.

As shown in FIG. 1, the control apparatus for a field synchronous motor according to an embodiment of the present invention includes a first sensor unit 10, a torque compensation unit (20), and a field current compensation unit (30).

The sensor unit 10 may be formed of a DC link sensor since it measures the voltage and current of the DC terminals.

Accordingly, the direct current power source can be formed of a vehicle DC battery.

The torque compensating unit 20 calculates a compensated torque command value Torque_comp based on the input torque command value and the current measured by the sensor unit 10. [

The field current compensation unit 30 calculates the voltage compensation value Vf_comp so that the voltage ripple and the current ripple at the DC stage are reduced based on the current measured by the first sensor unit 10. [

Therefore, the torque tracking performance for the motor control can be improved by calculating the input torque command value through the torque compensating unit 20 as the compensated torque command value.

Further, in the field winding synchronous motor, since the torque increases as the field current increases, the field current compensation section 30 calculates the voltage compensation value Vf_comp based on the current measured at the dc stage, and supplies it to the current controller 5 ) To adjust the voltage command Vf_control and input the adjusted voltage command Vf * to the PWM converter, and compensate the field current, thereby reducing the voltage ripple and the current ripple at the DC stage.

Further, by reducing the voltage ripple and the current ripple, the stability of the inverter and the inverter control device for motor control can be improved.

2, the torque compensating unit 20 of the control apparatus of the inverter according to the embodiment of the present invention may include an electrical estimating unit 22, an electrical calculating unit 24, and a controller 26. [

The electrical estimating section 22 calculates an expected electrical output value Pe_est based on the torque command value and the rotational angular velocity of the electric motor.

Therefore, it is possible to calculate the electric output expected when the motor torque is generated based on the torque command value and the current speed of the electric motor.

The electrical calculation section 24 calculates the electrical output value Pe based on the measured current and voltage of the DC stage.

Therefore, the electric output of the current motor can be calculated based on the current and voltage of the DC stage measured in real time.

The controller 26 compares the electrical output value Pe and the expected electrical output value Pe_est to calculate the compensated torque command value Torque_comp.

Thus, by comparing the predicted electrical output value with the current electrical output value for the torque command value input to the torque compensating section 20 and calculating the compensated torque command value (Torque_comp), it is possible to effectively control the torque generated in the electric motor have.

3, the electrical estimating unit 22 of the control apparatus for a field winding synchronous motor according to the embodiment of the present invention includes a torque estimating unit 40 and a data calculating unit 44 .

The torque estimating unit 40 calculates an estimated torque value based on the torque command value and the rotational angular velocity of the electric motor.

The data section 42 stores the efficiency table in which the motor efficiency is measured according to the torque command value and the rotational angular speed of the motor.

In addition, the efficiency table stores and measures the efficiency value according to the torque value and the electrical output value.

The calculating unit 44 calculates the estimated electrical output value based on the estimated torque value and the efficiency.

Therefore, the estimated electric output value Pe_est can be calculated by matching the electric output according to the efficiency value stored in the efficiency table with the estimated torque value Pm calculated by the torque estimating unit 40. [

4, the field current compensating unit 30 of the control apparatus for a field winding synchronous motor according to the embodiment of the present invention may include a current change amount calculating unit 32 and a voltage compensation calculating unit 34 have.

The current change amount calculation unit 32 calculates the current change amount of the DC termination.

Therefore, it is possible to know how much current ripple and voltage ripple in the dc stage are generated.

The voltage compensation calculation unit 34 calculates the voltage compensation value Vf_comp based on the current variation amount calculated so as to reduce the voltage ripple and the current ripple at the DC stage.

Thus, the field current compensation section 30 calculates the voltage compensation value Vf_comp based on the measured current change amount at the DC stage, adjusts the voltage command Vf_control generated by the current control section 5, Vf * is input to the PWM converter and the field current is compensated, so that voltage ripple and current ripple at the DC stage can be reduced.

By compensating the field current, it is possible to reduce the voltage ripple and the current ripple at the DC stage.

Further, by reducing the voltage ripple and the current ripple, the stability of the inverter and inverter control device for motor control can be improved.

The embodiments and the accompanying drawings described in the present specification are merely illustrative of some of the technical ideas included in the invention. Therefore, it is to be understood that the embodiments disclosed herein are not intended to limit the scope of the present invention but to limit the scope of the present invention. It will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims and their equivalents. It should be interpreted.

3: PWM inverter 4: Current command generator
5: current control unit 6:
7: PWM signal generating part 8: PWM converter
9: dq conversion unit 10: first sensor unit
12: second sensor unit 14: third sensor unit
16: Position sensor 20: Torque compensator
22; Electrical estimating unit 24: Electrical calculating unit
26: controller 30: field current compensation unit
32: current change amount calculation unit 34: voltage compensation calculation unit
40: torque estimating unit 42:
44:

Claims

A control device for a field winding linear synchronous motor which converts a DC power source to a driving power source of a field winding type motor,
A first sensor unit 10 for measuring the voltage and current of the DC stage;
A torque compensator 20 for calculating a compensated torque command value based on the input torque command value and the current measured by the first sensor unit 10;
A field current compensation unit (30) for calculating a voltage compensation value (Vf_comp) such that voltage ripple and current ripple of the DC stage are reduced based on the current measured by the first sensor unit (10);
And a control unit for controlling the field synchronous motor.

The method according to claim 1,
The torque compensating unit 10 includes:
An electrical estimator (22) for calculating a predicted electrical output value based on a torque command value and a rotational angular velocity of the electric motor;
An electrical calculation unit (24) for calculating an electrical output value based on the measured current and voltage;
A controller (26) for comparing the electrical output value and the predicted electrical output value to calculate the compensated torque command value;
And a control unit for controlling the field synchronous motor.

3. The method of claim 2,
The electrical estimating unit 22 estimates
A torque estimating unit (40) for calculating an estimated torque value based on the torque command value and the rotational angular velocity of the electric motor;
A data part (42) storing an efficiency table in which the motor efficiency is measured according to the torque command value and the rotational angular velocity of the motor;
A calculation unit (44) for calculating the predicted electrical output value based on the estimated torque value and the efficiency;
And a control unit for controlling the field synchronous motor.

The method according to claim 1,
The field current compensation unit (30)
A current variation amount calculating section (32) for calculating a current variation amount of the DC stage;
A voltage compensation calculation unit (34) for calculating a voltage compensation value (Vf_comp) based on the current variation amount calculated by the current variation calculation unit (32);
And a control unit for controlling the field synchronous motor.