KR100637674B1 - Motor driving control device - Google Patents

Abstract

The present invention relates to a motor drive control apparatus which compensates a delay of feedback current due to a current control period of a motor and compensates voltage fluctuations on an input power supply side to stably adjust gain by controlling pulse width modulation. The motor drive control apparatus receives a voltage variation compensator for detecting a voltage variation which is changed in comparison with an input power source by a load variation applied to the motor and compensates it to the input side, and receives the output signal of the voltage variation compensator in consideration of this. A current compensator for detecting a current delay component during current feedback and compensating for the compensation, and transmitting a current compensation to the input side, a current value flowing through a coil of the motor and a current delay component detected by the current compensator, and adding the current value. And a controller for subtracting and outputting the current command signal and a control unit for proportionally integrating the output signal of the calculator and controlling the gain corresponding to the voltage value output from the voltage change compensator. As a result, it is possible to prevent the unstable operation of the motor due to the voltage rise on the input power supply side, and to control the gain stably without deteriorating the control characteristics during acceleration and deceleration of the motor.

Description

Motor driving control device

 1 is a schematic structural diagram of a general motor drive control apparatus.

FIG. 2 is an internal block diagram schematically illustrating a controller and a PWM signal generator of the motor drive control apparatus shown in FIG. 1.

3 shows the current control timing of the motor drive control apparatus of FIG.

4 is an internal block diagram schematically showing a controller and a PWM signal generator of a motor drive control apparatus according to the present invention.

FIG. 5 is a schematic internal block diagram of the voltage shift compensator 110 shown in FIG. 4.

Explanation of symbols on the main parts of the drawings

20: PWM signal generator 30: rectifier 40: inverter

100: control unit 110: voltage fluctuation compensator 120,130: current compensator

The present invention relates to a motor drive control device, and more particularly, to compensate for the delay of the feedback current due to the current control period of the motor and to compensate for the voltage fluctuations at the input power supply side so as to stably adjust the gain by controlling pulse width modulation. It relates to a motor drive control device.

In general, as shown in FIG. 1, the conventional motor drive control apparatus includes a rectifier 30, an inverter 40, a controller 10, a PWM signal generator 20, and a rotation angle sensor 50.

The controller 10 shown in FIG. 1 is for applying the three-phase voltage command signals Vuc, Vvc, and Vwc to the PWM signal generator 20. As shown in FIG. 2, a pair of PI controllers ( 11 and 13 and a pair of gain controllers 12 and 14 and a multiplexer 15.

Each of the pair of PI controllers 11 and 13 includes a current value Iq obtained by subtracting the current value Iq obtained by converting the u-phase coil current Iu of the motor M into a synchronous coordinate system, and the current value Iqe and the motor. The current value Id converted from the v-phase coil current Iv of (M) to the synchronous coordinate system (coordinate system of d and q axes) is inputted by the current command signal Ide and the current value subtracted, and then proportionally integrated to each voltage value. And then apply it to a pair of gain controllers 12 and 14, respectively.

In addition, the pair of gain controllers 12 and 14 have a capacitor connected in parallel with the voltage value applied from each of the pair of PI controllers 11 and 13 to the input power supply side voltage, that is, the power input end side of the inverter 40. The gain is adjusted in accordance with a predetermined initial value Vdc.int of the voltage Vdc across both ends of (C), and the gain-adjusted voltage values Vqe and Vde are applied to the multiplexer 15.

In addition, the multiplexer 15 transmits the voltage values Vqe and Vde applied from the pair of gain controllers 12 and 14 to the rotation angle signal θ of the motor M applied from the rotation angle sensor 50. The voltage command signals Vuc, Vvc, and Vwc of three phases are converted to the PWM signal generator 20.

The PWM signal generator 20 generates a PWM signal (Vu, Vv, Vw) having a duty ratio corresponding to the voltage level of the three-phase voltage command signals (Vuc, Vvc, Vwc) applied from the controller 10. The three-phase voltage command signal Vuc is applied to the inverter 40 by subtracting the triangular wave output from the triangular wave generator (not shown) to the three-phase voltage command signals Vuc, Vvc, and Vwc applied from the control unit 10. PWM signals Vu, Vv, and Vw corresponding to the voltage levels of Vvc and Vwc are generated and applied to the inverter 40. Examples of such voltage command signals Vuc, Vvc and Vwc and PWM signals Vu, Vv and Vw are shown in FIG. 3, where Pn-1 and Pn denote current control timings.

In addition, the rectifier 30 rectifies a commercial AC voltage applied from the outside into a DC voltage and applies the inverter 40 to the inverter 40. The inverter 40 includes six switching elements Q1 to Q6 and six diodes D1 to D6. The six switching elements Q1 to Q6 each have a current in each phase coil u, v, w of the motor M by means of a PWM signal applied from the PWM signal generator 20. 6 diodes D1 to D6 are generated when the respective switching elements Q1 to Q6 are turned off after applying current to the coils u, v and w of each phase of the motor M. Each reflux voltage is refluxed.

In addition, the rotation angle sensor 50 detects a rotation angle of the motor 50 and applies a rotation angle signal θ corresponding thereto to the controller 10. In addition, when a current is applied to each phase coil u, v, w from the inverter 40, the motor M is driven at a speed corresponding to the applied current value.

However, the above conventional motor drive control device has the following problems.

First, when the motor M rotates at a high speed and then decelerates, the current applied to each phase of the motor M through the inverter 20 as the motor M operates as a generator due to a sudden load change. The capacitor C flows backward to the input power supply end. As a result, the voltage on the input power supply side, that is, the voltage Vdc across the capacitor C rises abnormally. As a result, an overcurrent above the normal value is applied to the motor M, thereby reducing mechanical noise and vibration during deceleration. Operation of the motor M becomes unstable such that the rotational speed and torque of the motor deviate from normal values. In addition, although the input power supply voltage Vdc is changed in this way, as shown in FIG. 2, the gain controllers 12 and 14 continuously adjust the gain based only on the initial input power supply voltage Vdc.int, thereby improving stability and stability of the system. There is a disadvantage in that the control characteristics are lowered.

Second, in the first current control timing Pn-1 of FIG. 3, current control of the motor is performed by the initial current command signal. Thereafter, in the second current control timing Pn, the current flowing through each phase of the motor is sensed by the voltage command signal generated as a result of the first current control timing Pn-1, and the control unit 10 detects the current value. The current value applied to the motor is adjusted by comparing with the current command signal.

However, the feedback current of the second current control timing Pn actually includes a current delay component due to the time delay between the control timings. In fact, if the gain is increased without considering the current delay component, the error component becomes larger, and thus the motor The same control characteristic is not achieved at the time of acceleration and deceleration, and the gain gradually decreases.

Therefore, there are problems in that the acceleration and deceleration of the motor is not only limited, but also the increase in the control gain is limited due to the above two reasons.

The present invention is to solve the above problems, the motor drive control to compensate the delay of the feedback current due to the current control period of the motor and compensate the voltage fluctuations on the input power supply side to control the gain stably by controlling the pulse width modulation The purpose is to provide a device.

Motor drive control apparatus according to the present invention for achieving the above object, the motor drive control device for driving the motor by applying a current from the inverter to the coil of each phase in accordance with the current command signal and feedback the detected current value of each phase to the input side In the present invention, a voltage variation compensator which detects a voltage variation which is changed in comparison with an input power source by a load variation applied to the motor and compensates it to the input side, receives an output signal of the voltage variation compensator and takes into account the current delay during current feedback. And a current compensator for detecting a component and transmitting a compensation current to the input side to compensate for the component.

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

First, since the basic configuration of the present invention is the same as in FIG. 1 except for the controller 100, redundant description thereof will be omitted and the control unit of the present invention will be described in detail with reference to FIGS. 3-5. Shall be.

Figure 4 is a block diagram showing the internal structure of the control unit 100 according to a preferred embodiment of the present invention, as can be seen with reference to the drawings, the control unit of the present invention is a pair of PI controller (101, 103), A pair of gain controllers 102 and 104, a pair of current compensators 120 and 130, a voltage fluctuation compensator 110 and a multiplexer 105.

In Fig. 4, each of the pair of PI controllers 101 and 103 has a current value Iq obtained by converting the u-phase coil current Iu of the motor M into a synchronous coordinate system and the second current control timing (Fig. 3). In order to compensate for the current delay component generated by the time delay between the current control timing at the feedback current of Pn), the compensation current value ΔIq calculated by the current compensator 120 is added to each other and the addition value Iq + ΔIq is added. The current value subtracted from the current command signal Iqe, the current value Id obtained by converting the v-phase coil current Iv of the motor M into the synchronous coordinate system, and the feedback current of the second current control period Pn of FIG. In order to compensate the current delay component generated by the time delay between the current control timings, the compensation current value ΔId calculated by the current compensator 120 is added to each other, and the addition value Id + ΔId is added to the current command signal Ide. Take the current value subtracted from the current signal, convert it into a voltage value by proportionally integrating them, and then It is adapted to be applied to each.

In addition, the pair of gain controllers 102 and 104 respectively adjust the gains according to the output values of the voltage fluctuation compensator 110 to the voltage values applied from each of the pair of PI controllers 101 and 103, respectively. Voltage values Vqe and Vde are applied to the multiplexer 105.

In addition, the multiplexer 105 has three voltage values Vqe and Vde applied from the pair of gain controllers 102 and 104, respectively, corresponding to the rotation angle signal θ of the motor rotor applied from the rotation angle sensor 50. The voltage command signals Vuc, Vvc, and Vwc of the phases are converted and applied to the PWM signal generator 20.

And, as can be seen with reference to Figure 5, the voltage fluctuation compensator 110, the power detector 111, the polarity determination unit 112, the reverse current detector 113, the voltage converter 114, the voltage rise calculation unit And a voltage increase adder 116. As shown in FIG.

In FIG. 5, the power detector 111 adds the current value Iqe obtained by converting the u-phase coil current Iu of the motor M into the synchronous coordinate system and the voltage value Vqe output from the gain controller 102. The power value is obtained by multiplying the obtained value by the value obtained by adding the voltage value output from the gain controller 104 to the current value Ide obtained by converting the v-phase coil current Iv of the motor M into the synchronous coordinate system. The power value of the motor M is detected by multiplying the obtained power value by a preset gain value 2/3.

In addition, the polarity determination unit 112 passes the power detection value only when the power detection value of the motor M output from the power detection unit 111 is (+), and the reverse current detection unit 113 The current detection value of the motor M is obtained by dividing the power detection value passed by the polarity determination unit 112 by the voltage value output from the voltage increase addition unit! 16.

In addition, the voltage converter 114 converts the current value of the motor M obtained by the reverse current detector 113 into a voltage value, and the voltage rise calculator 115 converts the voltage value by the voltage converter 114. Divided voltage value by the capacitance value of the capacitor C installed at the input power terminal of the inverter 40, the voltage increase of the power input terminal side by the current flowing back from each phase coil of the motor M, that is, the capacitor C The voltage increase for both ends of is calculated.

The voltage increase adder 116 adds the voltage increase calculated by the voltage increase calculator 115 to a predetermined initial value Vdc.int of the voltage Vdc across the input power supply, that is, the capacitor C. The added value is applied to the pair of gain controllers 102 and 104.

In addition, the current compensation values ΔIq and ΔId reflected by the current compensators 120 and 130 to the input current side are obtained by the following equation (1).

ΔIu = K * (Vuc-Vvc) + K * (Vuc-Vwc)

ΔIv = K * (Vvc-Vuc) + K * (Vvc-Vwc) ------ (1)

ΔIw = K * (Vwc-Vuc) + K * (Vwc-Vvc)

Here, the proportionality constant K = Vdc / L, Vdc is the DC power supply voltage, and L represents the inductance of the motor M to be controlled.

When the current compensation values? Iu,? Iv,? Iw flowing through each phase calculated by the above formula (1) are converted into the synchronous coordinate system, the current compensation values? Iq,? Id are obtained. Equation (1) shows that when the current flowing through each phase of the motor is the same, the current flowing through the motor does not change, but in practice, current delay component is generated from the current flowing through each phase due to the time delay between the current control cycles. The current is changed, and the change is then calculated to be calculated by comparing the current value detected in one phase with that of the other phase.

The operation of the present invention having the configuration as described above will be described in detail with reference to FIGS. 1 and 3-5.

In the initial state, when a commercial AC voltage is input from the outside, the rectifier 30 converts the commercial AC voltage into a DC voltage and outputs the DC voltage. The DC voltage thus converted is smoothed in the capacitor C and the inverter is stabilized. 40).

In addition, the rotation angle sensor 50 detects a rotation angle of the motor M and applies a rotation angle signal θ corresponding thereto to the controller 100.

At this time, when an operation signal is input to the controller 100 from the outside, each of the pair of PI controllers 101 and 103 is the current value Iq of converting the u-phase coil current Iu of the motor M into the synchronous coordinate system. And the compensation current value? Iq calculated by the current compensator 120 are added to each other, and the current value obtained by subtracting this addition value Iq +? Iq from the current command signal Iqe and the v-phase coil of the motor M. The current value Id converted from the current Iv to the synchronous coordinate system and the compensation current value ΔId calculated by the current compensator 120 are added to each other, and this addition value Id + ΔId is added to the current command signal Ide. A subtracted current value is input from the current controller, proportionally integrated into a voltage value, and then applied to each of the pair of gain controllers 102 and 104.

In addition, the gain controllers 102 and 104 adjust the gains according to the output values of the voltage fluctuation compensator 110 and the voltage values applied from the pair of PI controllers 101 and 103, respectively. Vqe, Vde) is applied to the multiplexer 105.

At this time, the output value output from the voltage fluctuation compensator 110 becomes a predetermined initial value (Vdc. Int) for the voltage (Vdc) of the input power terminal side of the inverter 40.

In addition, the multiplexer 105 is a three-phase voltage command corresponding to the rotation angle signal θ of the motor rotor applied from the rotation angle sensor 50 to the voltage values Vqe and Vde applied from the gain controllers 102 and 104, respectively. The signal is converted to the signals Vuc, Vvc, and Vwc and applied to the PWM signal generator 20, and the PWM signal generator 20 is configured to control the three-phase voltage command signals Vuc, Vvc, and Vwc applied from the controller 100. A PWM signal having a duty ratio corresponding to the voltage level is generated and applied to the inverter 40. In addition, the inverter 40 operates the respective switching elements Q1 to Q6 according to the PWM signal applied from the PWM signal generator 20 to supply current to each phase coil u, v, w of the motor M. FIG. To operate the motor (M).

In this state, when the speed of the motor M decreases rapidly, the motor M operates as a generator due to a sudden load change, and the current flowing through each phase coil of the motor M flows back to the input power supply terminal, resulting in a capacitor C. While charging the battery, the voltage Vdc at the input power supply terminal is abnormally increased compared to the initial value Vdc.int.

At this time, such an abnormal increase in the input power supply voltage Vdc is checked in the voltage fluctuation compensator 110, and a detailed operation thereof is as follows.

First, the voltage value output from the gain controller 102 to the current value lq of the power detection unit 111 of the voltage rise detection unit 110 converted the u-phase coil current Iu of the motor M into the synchronous coordinate system ( The value obtained by adding Vqe) and the voltage value Vde output from the gain controller 104 are added to the current value ld obtained by converting the v-phase coil current Iv of the motor M into a synchronous coordinate system. The power value is obtained by multiplication, and the power value thus obtained is multiplied by a preset gain value 2/3 to detect the power value of the motor M.

At this time, since the current flowing in the coil of each phase of the motor M is flowing back to the input power supply end side, the detection value of the u-phase coil current Iu and the detection value of the v-phase coil current Iv are represented by (+). As a result, the power detection value of the motor M has a positive value.

For reference, when the current flowing through the coil of each phase of the motor M does not flow backward, the motor detects the u-phase coil current Iu and the v-phase coil current Iv because the detected value of the motor is negative. The power detection value of (M) has a value of (-).

The polarity determination unit 112 passes the power detection value only when the power detection value of the motor M output from the power detection unit 111 is (+), but is output from the power detection unit 111. Since the power detection value of the motor M thus obtained is positive, the power detection value is passed and applied to the reverse current detection unit 113.

That is, when the power detection value of the motor M output from the power detection unit 111 is (−), the current flows normally in each phase of the motor M, and the power of the motor M output from the power detection unit 111 is maintained. If the power detection value is (+), the current flowing in each phase of the motor M is reversed to the input power supply end side. Therefore, the polarity determination unit 112 has a current flowing in each phase of the motor M in its input power supply. Only the power detection value of the motor M detected in the state of flowing back to the short side is passed.

In addition, the reverse current detector 113 obtains a current value of the motor M by dividing the power detection value passed by the polarity determination unit 112 by the voltage value output from the voltage increase adder 116, and the voltage converter 114. ) Integrates the current value of the motor M obtained by the reverse current detection unit 113 and converts it into a voltage value.

In addition, the voltage rise calculator 115 divides the voltage value converted by the voltage converter 114 by the capacitance value of the capacitor C installed at the input power supply terminal of the inverter 40 to reverse the current flowing from the motor M. The voltage increase applied to the capacitor C is calculated.

In addition, the voltage increase adder 116 calculates the voltage calculated by the voltage increase calculator 115 at a predetermined initial value Vdc.int of the voltage at the input power supply side, that is, the voltage Vdc across the capacitor C. The value obtained by adding the increase is applied to the pair of gain controllers 102 and 104 and the pair of current compensators 120 and 130, respectively. That is, the voltage increase adder 116 applies an abnormally elevated voltage detection value at the input power supply terminal to the pair of gain controllers 102 and 104 and the pair of current compensators 120 and 130, respectively.

As a result, the current compensators 120 and 130 reflect the current delay component to the current command signal according to Equation (1) above, and the voltage calculated by the voltage fluctuation compensator 110 at a proportional constant K = Vdc / L. The compensation current can be accurately estimated by using the Vdc value reflecting the increase, and the compensation current value thus accurately reflected is input to the input side of the pair of PI controllers 101 and 103 and transferred to the gain controllers 102 and 104.

Accordingly, the gain controllers 102 and 104 receive the output signals of the PI controllers 101 and 103 and the voltage fluctuation compensator 110 and abnormally adjust the gains of the output voltages of the PI controllers 101 and 103 reflecting the compensation current value. The voltage level of the three-phase voltage command signals Vuc, Vvc, and Vwc. Output from the multiplexer 105 is varied according to the voltage Vdc of the input power supply terminal side of the elevated inverter 40. The duty ratio of the PWM signal output from the PWM signal generator 20 is readjusted. As a result, the current value applied from the inverter 40 to each phase of the motor M is adjusted to correspond to the voltage Vdc at the input power supply terminal side which is abnormally increased.

As described above, the motor drive control apparatus according to the present invention compensates the delay of the feedback current due to the current control period of the motor and compensates the voltage variation on the input power supply side to adjust the current value applied to the motor, thereby adjusting the voltage on the input power supply side. It prevents the unstable operation of the motor due to the rise and does not deteriorate the control characteristics during acceleration and deceleration of the motor, thereby controlling the gain stably.

Claims (6)

In the motor drive control apparatus for applying a current from the inverter to the coil of each phase in accordance with the current command signal, the current value of each phase is fed back to the input side to drive the motor, A voltage fluctuation compensator for detecting a voltage fluctuation changed in comparison with an input power source by a load fluctuation applied to the motor and compensating it to the input side; and And a current compensator configured to receive an output signal of the voltage fluctuation compensator and take a current into consideration and detect a current delay component during current feedback and transfer a compensating current to the input side to compensate for the current delay component. The method of claim 1, A calculator which adds a current value flowing through a coil of the motor and a current delay component detected by the current compensator, and then subtracts the added current value with the current command signal and outputs it; And a controller for proportionally integrating the output signal of the calculator and controlling the gain corresponding to the voltage value output from the voltage change compensator. The method of claim 1, The current compensator is modified to calculate the compensation current. ΔIu = K * (Vuc-Vvc) + K * (Vuc-Vwc) ΔIv = K * (Vvc-Vuc) + K * (Vvc-Vwc) ΔIw = K * (Vwc-Vuc) + K * (Vwc-Vvc) Vuc is a first PWM command signal applied to the PWM signal generator from the multiplexer, Vvc is a second PWM command signal applied to the PWM signal generator from the multiplexer, and Vwc generates a PWM signal from the multiplexer. The third PWM command signal applied to the negative, and K is a proportional constant, Vdc / L, Vdc is a DC power supply voltage, L is a motor drive control device, characterized in that the inductance of the motor (M). The method of claim 1, The voltage fluctuation compensator, A power detector detecting power of the motor; A polarity determination unit which passes the power detection value only when the polarity of the power detection value detected by the power detection unit is a set polarity; A reverse current detection unit for obtaining a current value of the motor flowing back to the input power supply side from the power detection value passed by the polarity determination unit; A voltage converter converting the motor current obtained from the reverse current detector into a voltage value; A voltage rise calculator configured to calculate a voltage increase of the input power terminal by dividing the voltage value converted by the voltage converter by the capacitance of the capacitor; And a voltage rise adder which adds and outputs a voltage rise calculated by the voltage rise calculator to the initial voltage value of the input power terminal. The method of claim 4, wherein the power detection unit, And controlling the electric power of the motor by multiplying the current flowing through the coil of the motor by the output value of the gain controller. The method of claim 4, wherein the reverse current detection unit, And a current detection value of the motor by dividing a power detection value detected by the power detection unit by an output value of the voltage increase addition unit.

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