WO1998042067A1 - Convertisseur electrique, unite de commande de moteur a courant alternatif et leur procede de commande - Google Patents

Convertisseur electrique, unite de commande de moteur a courant alternatif et leur procede de commande Download PDF

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Publication number
WO1998042067A1
WO1998042067A1 PCT/JP1997/000909 JP9700909W WO9842067A1 WO 1998042067 A1 WO1998042067 A1 WO 1998042067A1 JP 9700909 W JP9700909 W JP 9700909W WO 9842067 A1 WO9842067 A1 WO 9842067A1
Authority
WO
WIPO (PCT)
Prior art keywords
delay
compensation value
delay compensation
motor
switching element
Prior art date
Application number
PCT/JP1997/000909
Other languages
English (en)
Japanese (ja)
Inventor
Hironori Ohashi
Makoto Takase
Hiroyuki Tomita
Seiji Ishida
Masaki Sugiura
Original Assignee
Hitachi, Ltd.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Hitachi, Ltd. filed Critical Hitachi, Ltd.
Priority to PCT/JP1997/000909 priority Critical patent/WO1998042067A1/fr
Priority to JP54032298A priority patent/JP3329831B2/ja
Publication of WO1998042067A1 publication Critical patent/WO1998042067A1/fr

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Classifications

    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
    • H02M7/42—Conversion of dc power input into ac power output without possibility of reversal
    • H02M7/44—Conversion of dc power input into ac power output without possibility of reversal by static converters
    • H02M7/48—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
    • H02M7/53—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal
    • H02M7/537—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters
    • H02M7/5387—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters in a bridge configuration
    • H02M7/53871—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters in a bridge configuration with automatic control of output voltage or current
    • H02M7/53875—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters in a bridge configuration with automatic control of output voltage or current with analogue control of three-phase output
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M1/00—Details of apparatus for conversion
    • H02M1/38—Means for preventing simultaneous conduction of switches
    • H02M1/385—Means for preventing simultaneous conduction of switches with means for correcting output voltage deviations introduced by the dead time

Definitions

  • the present invention relates to a power conversion device, an AC motor control device, and a control method thereof.
  • the present invention relates to an AC motor control device that drives an AC motor using a power converter using a switching element.
  • the present invention is applicable to all control devices using a power converter using a switching element, and can be used, for example, in a power converter such as a PWM converter.
  • a three-phase power converter 2 shown in FIG. 12 is generally used as a control device for converting the power to a variable frequency power supply using a switching element and controlling the speed of the AC motor 1.
  • reference numeral 3 denotes a control circuit
  • CT denotes a current detector for detecting an output current.
  • This power converter is characterized in that the upper and lower arms of the switching element are connected in series to a so-called three-phase bridge for each output phase, and are exclusively switched. Since a semiconductor switching element such as an IGBT is used as the switching element and the ON / OFF operation has a delay, the ON signal of the other switching signal is delayed with respect to the OFF signal of one of the upper and lower arms of each phase.
  • the control circuit 3 receives the voltage command V * from the control arithmetic unit 31 such as the motor current and outputs the PWM pattern.
  • An on-delay generator 34 which outputs the signal to the generator 3 and delays the on-signal only while the switching element is off, is required.
  • the on-delay When viewed from a control device such as a motor, the on-delay is non-linear with respect to the direction of the output current and the like, and as shown in FIG. 10, the output current (an example of the line current iu is shown. (The same applies to iv and iw), which degrades control characteristics and causes torque ripple and other factors. (Fig. 10 shows the output current fundamental wave Y1 and the fifth harmonic wave Y5 at the top. The middle stage shows the distorted output current iu, and the lower stage shows the id obtained by d-q conversion of the current and DC display as described later). For this reason, recently, in addition to the on-delay generator 34, an on-delay compensator 33 shown in FIG.
  • the on-delay compensator 33 considers the direction (polarity sgn (i)) of the output current i (iu, iv, iw) during the on-time T on of the signal input from the PWM pattern generator 32.
  • the ray compensation value Td is added to compensate for the on-delay component as follows.
  • this on-delay compensation value T d is the time from when an ON signal is input to the switching element to when it is actually turned on, t on, and the time from when an off signal is input to when it is actually turned off is t off.
  • the time during which the signals input from the PWM pattern generator 32 to the switching elements of the upper and lower arms are simultaneously off is defined as the on-delay time T dead
  • T dead, t on, and t off vary depending on the individual characteristics of hardware such as switching elements and control circuit components, so that T d also varies. Therefore, even if the on-delay compensation value T d is set to a specific value and the on-delay compensation is performed, compensation can be performed by the amount that T d varies. I can't.
  • the Td varies for each power converter due to the hardware, so the current is distorted when viewed as a motor control device, and the above-mentioned on-delay generator 34 and on-delay compensator 33 are still insufficient. Generates torque ripple. In order to prevent this as much as possible, conventionally, it was necessary to use a selected product for the hardware (such as a photo bra) for each term in equation (1) or manually adjust the power converter individually.
  • An object of the present invention is to provide an inexpensive control device in which a control device automatically adjusts an on-delay compensation value Td.
  • the second object is to provide a highly accurate control device by suppressing torque ripple and the like of the control device by this automatic adjustment. Disclosure of the invention
  • an on-delay compensation value calculator 35 that automatically inputs the current and voltage and adjusts the on-delay compensation value Td is provided. On-delay compensation value calculation is started by the calculation start signal.
  • the on-delay compensation value calculator 35 detects the current and the voltage, extracts the characteristic amount such as the current distortion by the on-delay compensation, and calculates the on-delay compensation value.
  • FIG. 1 is a control block diagram according to a first embodiment of the present invention.
  • FIG. 2 is a control flowchart of the first embodiment of the present invention.
  • FIG. 3 shows the relationship between the current controller and the carrier frequency for explaining the operation principle of the first embodiment of the present invention.
  • FIG. 4 is a control block diagram according to a second embodiment of the present invention.
  • Fig. 5 shows the current waveform when the on-delay is not compensated.
  • FIG. 6 shows a relationship between harmonics and an on-delay compensation value for explaining the operation principle of the second embodiment of the present invention.
  • FIG. 7 is an embodiment of a control port according to the second embodiment of the present invention.
  • FIG. 8 shows another embodiment of the control port according to the second embodiment of the present invention.
  • FIG. 9 is a control block diagram of the third embodiment of the present invention.
  • FIG. 10 is an example of a line current waveform when on-delay is not compensated.
  • FIG. 11 is a control flowchart of a third embodiment of the present invention.
  • FIG. 12 is a control block diagram of a conventional control device.
  • FIG. 1 shows a control block diagram of a device in which an AC motor 1 is driven by a power converter 2 and controlled by a control circuit 3.
  • the control circuit 3 controls speed control, current control, ratio control between output voltage and output frequency (hereinafter referred to as VZf control), and so-called vector control in which the excitation component and torque component are separated by vector.
  • Calculator 31 PWM pattern generator 32 for generating gate signals for power converter 2, on-delay compensator 33, on-delay generator 34, and on-delay compensation value calculator 3 according to the present invention 5a etc.
  • CT is a current detector that detects an output current.
  • the control calculator 31 gives a voltage command V * to the PWM pattern generator 32.
  • the PWM pattern generator 32 uses a well-known triangular wave comparison PWM or the like.
  • the switching element of the power converter 2 semiconductor such as IGBT
  • the on time T on of the element is output.
  • DC power V dc is converted into AC power, and AC motor 1 is rotationally driven.
  • the DC power supply V dc may be obtained by rectifying the AC.
  • the power converter 2 connects the U-phase, V-phase, and W-phase switching elements in series with the upper and lower arms. And switch exclusively. Also, the on-delay generator 34 is provided to prevent a short circuit of the switching element. Furthermore, an on-delay compensator 33 is provided for suppressing current distortion.
  • the variation in the on-delay compensation value Td, which cannot be compensated by the on-delay compensator 33, due to the hardware is automatically measured by the on-delay compensation value calculator 35a, and the variation is calculated by the hardware.
  • the purpose is to provide a low-cost, high-precision control device that eliminates variations.
  • the on-delay compensation value calculator 35a of this embodiment starts operation in a flow chart as shown in FIG. 2 when an on-delay compensation value calculation start signal Std is given from outside the control device (STEP 100). ⁇ STEP103).
  • the on-delay compensation value calculator 35 a is supplied to the current controller 3 1 1 in the control calculator 31 so that a DC current flows between the u and V phases.
  • the command I * is output, and the carrier frequency f 1 that determines the switching frequency of the switching element of the power converter 2 is output to the PWM pattern generator 32.
  • the current controller 311 is, for example, a well-known PI (proportional-integral) controller, which is sufficient (STEP OOa).
  • the on-delay compensation value calculator 35a observes that the current control output V * of the current controller 311 1 has become stable, and sets the current control output V * as a voltage command V between u and the V phase. (STEP OOb). Similarly, the carrier frequency The current is controlled with a frequency f 2 different from Equation 1 and a DC current command I * (STEP100c), and when the current control output V * is stabilized, the current control output V * is set to the u-V phase voltage command V 2 * uv (STEP100d).
  • V dc is the DC voltage of the power converter 2.
  • T duv, T dvw, and T dwu are used as the on-delay compensation values for each phase.
  • processing such as averaging may be performed as in Eq. (5) and compensation may be performed using T duvw for all three phases. It is.
  • the on-delay compensation value T d is independent of the switching frequency of the switching element as shown in Eq. (1). However, if the operating cycle of the switching element (the reciprocal of the carrier frequency) becomes longer, the on-delay compensation value T d becomes a percentage And the effect of the on-delay compensation value Td is reduced, and the current waveform distortion is also reduced. Conversely, if the operation cycle of the switching element is shortened, the ratio of the switching element to the cycle is increased, and the effect is also increased. Therefore, the difference between the current control outputs V * in these two operation cycles can be used as the on-delay compensation value T d. Fig. 3 illustrates this relationship.
  • Fig. 3 shows the carrier frequency fc on the horizontal axis and the current control output V * on the vertical axis. Is taking.
  • the DC current command is set to the DC current command I * so that the output current becomes DC, so if the carrier f2 is selected at a low frequency, only the voltage drop RI * of the resistance R of the AC motor 1 is reduced. It is possible to extract the frequency current control output V * that appears as an effect of on-delay.
  • the carrier frequency is gradually increased to f1
  • the current control output V * is the sum of the voltage drop RI * and the on-delay voltage drop. Therefore, if this difference is taken, the voltage drop RI * cancels out and becomes the voltage of the on-delay voltage drop.
  • the on-delay compensation value Td can be obtained by converting this to time at the frequency f1 as in Equations (2) to (4).
  • the switching element of power converter 2 is an IGBT, set f1 to 10 kHz or more and f2 to 5 kHz or less. In the case of bipolar drainage, set f1 to 2 kHz or more and f2 to 1 k. It is desirable to set it to Hz or less.
  • the on-delay compensation value Td is obtained by using a DC current, there is a possibility that the on-delay compensation value Td may be slightly deviated from the on-delay compensation value Td obtained by using an alternating current. It goes without saying that the obtained on-delay compensation value T d may be multiplied by a weighting factor.
  • FIG. 1 is provided with an AC voltage generator 312, and the on-delay compensation value calculator 35b is provided with a Fourier transformer (high-speed FFT) or a Waltz converter for obtaining harmonics.
  • the major difference is that the embodiment obtains the on-delay compensation value Td with direct current instead of the direct current.
  • a current such as Y13 in Fig. 5 flows as the output current.
  • FIG. 7 shows a flow chart of the second embodiment (STEP110 to STEP112).
  • C Excitation is first performed between u and v in the same manner as in the previous embodiment (STEP11 Oa).
  • a Fourier transformer (high-speed FFT) A3 uv is taken out by means of an Orsh converter or the like (STEPl l Ob), and the on-delay compensation value T d uv that minimizes the A3 uv is determined by the least square method or the like (STEPl l Oc) .
  • the on-delay compensation values Tduv, Tdvw, and Tdwu are obtained.
  • single-phase AC excitation is performed so as not to rotate the motor.
  • the on-delay compensation value may be adjusted using a flowchart as shown in FIG. Can be obtained (STEP120-STEP122).
  • the AC motor 1 is driven by V / f operation (STEP120), and the current waveform at this time is a waveform containing the fifth and seventh harmonics as shown in Fig. 10. That is.
  • at step 120a at least one of A5 or A7 is extracted by a Fourier transformer (high-speed FFT) or a ⁇ orsh converter, and driven by the least-squares method. Others are the same, and the description is omitted.
  • the on-delay compensation T d can be obtained for each phase, the method of averaging and multiplying the weighting factor can be similarly performed as shown in the first embodiment. Needless to say.
  • the current and the like differ depending on the frequency and voltage value for exciting the AC motor 1, when determining the on-delay compensation T d more precisely, as shown in the first embodiment, the individual parameters ( It is clear that the voltage and frequency can be determined and obtained.
  • the third embodiment is a method in which the motor may be rotated as in the second method of the second embodiment described above.Since the AC motor 1 is actually rotated, more accurate on-delay compensation is performed. T d can be determined.
  • the difference from the second embodiment in the configuration is that the Fourier transformer (fast FFT) or Walsh transform is included in the on-delay compensation value calculator 35c as shown in Fig. 9. A converter and the like become unnecessary, and i-o- becomes unnecessary.
  • a dq converter 314 is required in the control arithmetic unit 31.
  • the d-q converter 3 1 4 is an AC voltage generator 3 1 3 generated by the signal VZ f (output signal from the on-delay compensation value calculator 35 c to the AC voltage generator 3 13).
  • the currents id and iq on the d--q axes can be obtained by performing coordinate conversion on the three-phase line currents using the d-q converter 314.
  • the conversion equation is, for example, as shown in equation (6).
  • V Zf driving is performed in three phases, and if on-delay compensation is not performed, the waveform will be as shown by the line current i u in FIG.
  • the third harmonic has a three-phase waveform with a phase shift of 120 ° and a sixth harmonic, as shown in Fig. 5. Since they cannot be generated, the corresponding harmonics appear in the 5th and 7th order as a distorted waveform (Y157) as shown in the figure.
  • a DC current pulsating in the sixth order as shown in id in FIG. 10 is obtained. Therefore, an on-delay compensation value that minimizes the sixth-order component may be obtained.
  • the on-delay compensation value can be obtained by using a Fourier transformer (fast FFT) or a Walsh transformer in the on-delay compensation value calculator 35c as in the second embodiment.
  • the following shows that the on-delay compensation value can be obtained without using such a Fourier transformer (fast FFT) or a Walsh transformer.
  • FIG. 11 shows the mouthpiece of the third embodiment described above (STEP130 to STEP132).
  • a imean ⁇ ⁇ l d (j) ⁇ l dm in where i dmax: the maximum value of id and i dmin: the minimum value of id.
  • the on-delay compensation value is automatically calculated.
  • the on-delay compensation value calculated value may be an abnormal value due to a failure of the power converter or the like.
  • a mechanism to prevent abnormal operation should be provided by adding a limiter with the value of equation (1) as a typ. Value. I can judge.
  • the on-delay compensation value calculation start signal Std can be given at an arbitrary timing by providing a switch or the like from outside the control circuit 3. In this case, for example, it can be performed at the time of product shipment or at the time of maintenance after installation, if necessary. Or if you want to do it at power on The Std signal should be automatically generated when the power is turned on. In this case, the Std signal can be generated inside the control circuit 3.
  • all of the embodiments described above can coexist in the on-delay compensation value calculator 35, and if it is possible to select which method to obtain the on-delay compensation value from outside the control circuit 3, the application will be expanded and the AC motor The on-delay compensation value can be obtained irrespective of the load condition.
  • the on-delay compensation value calculator described in the present invention can be used for a PWM converter and other power converters. Industrial applicability
  • the deviation of the on-delay compensation value due to the variation of the individual power converters is automatically adjusted, torque ripple due to the deviation of the on-delay compensation value can be prevented, and a highly accurate control device can be realized.
  • the automatic adjustment increases the allowable range of hardware variation, which has the effect of realizing an inexpensive control device.

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Control Of Ac Motors In General (AREA)

Abstract

La présente invention concerne un régulateur automatique à valeur de compensation temporisée et une unité de commande haute précision, peu coûteuse. Un calculateur (35) de valeur de compensation temporisée est monté dans un circuit de commande (3). On mesure le courant d'un moteur (1) à courant alternatif et la tension d'un convertisseur électrique (2) et on fait varier la fréquence de façon à calculer une valeur de compensation temporisée. Un convertisseur de Fourier est intégré au calculateur (35) de valeur de compensation temporisée. On fait varier la valeur de compensation temporisée de façon à réduire les harmoniques et les ondulations du courant jusqu'à obtenir une valeur de compensation temporisée appropriée. Du fait que la déviation de la valeur de compensation temporisée, provoquée par la variation du convertisseur de puissance lui-même, peut être commandée automatiquement, on empêche une ondulation de couple provoquée par la variation de la valeur de compensation temporisée, ce qui permet de réaliser une unité de commande haute précision. En outre, du fait qu'on accepte l'augmentation de la variation du matériel, on peut réaliser une unité de commande peu coûteuse.
PCT/JP1997/000909 1997-03-19 1997-03-19 Convertisseur electrique, unite de commande de moteur a courant alternatif et leur procede de commande WO1998042067A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
PCT/JP1997/000909 WO1998042067A1 (fr) 1997-03-19 1997-03-19 Convertisseur electrique, unite de commande de moteur a courant alternatif et leur procede de commande
JP54032298A JP3329831B2 (ja) 1997-03-19 1997-03-19 電力変換装置、交流モータ制御装置、及びそれらの制御方法

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/JP1997/000909 WO1998042067A1 (fr) 1997-03-19 1997-03-19 Convertisseur electrique, unite de commande de moteur a courant alternatif et leur procede de commande

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WO1998042067A1 true WO1998042067A1 (fr) 1998-09-24

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7362069B2 (en) 2003-08-18 2008-04-22 Kabushiki Kaisha Yaskawa Denki Voltage source inverter control method
JP2010228701A (ja) * 2009-03-30 2010-10-14 Jtekt Corp デッドタイム設定方法、モータ制御装置および電動パワーステアリング装置
US10910984B2 (en) 2015-05-20 2021-02-02 Mitsubishi Electric Corporation Power conversion device and vehicle drive system to which same is applied

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101076216B1 (ko) 2011-09-07 2011-10-26 (주)스페이스원 Ｉｇｂｔ 회로를 이용한 정밀 가공 제어 장치 및 그 제어 방법

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH03143287A (ja) * 1989-10-27 1991-06-18 Hitachi Ltd 電圧形インバータの制御方法
JPH08126335A (ja) * 1994-10-20 1996-05-17 Hitachi Ltd 電力変換器の制御方法および装置

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH03143287A (ja) * 1989-10-27 1991-06-18 Hitachi Ltd 電圧形インバータの制御方法
JPH08126335A (ja) * 1994-10-20 1996-05-17 Hitachi Ltd 電力変換器の制御方法および装置

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7362069B2 (en) 2003-08-18 2008-04-22 Kabushiki Kaisha Yaskawa Denki Voltage source inverter control method
JP2010228701A (ja) * 2009-03-30 2010-10-14 Jtekt Corp デッドタイム設定方法、モータ制御装置および電動パワーステアリング装置
US10910984B2 (en) 2015-05-20 2021-02-02 Mitsubishi Electric Corporation Power conversion device and vehicle drive system to which same is applied

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