JPH07288980A - Voltage controller for power converter - Google Patents
Voltage controller for power converterInfo
- Publication number
- JPH07288980A JPH07288980A JP6099215A JP9921594A JPH07288980A JP H07288980 A JPH07288980 A JP H07288980A JP 6099215 A JP6099215 A JP 6099215A JP 9921594 A JP9921594 A JP 9921594A JP H07288980 A JPH07288980 A JP H07288980A
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- Prior art keywords
- current
- fluctuation
- power
- load
- voltage
- Prior art date
- Legal status (The legal status 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 status listed.)
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- Control Of Ac Motors In General (AREA)
- Inverter Devices (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、例えば誘導電動機の駆
動を行うインバータ回路の入力電源のサイリスタコンバ
ータ例の負荷補償を行う電力変換装置の電圧制御装置に
関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a voltage control device of a power converter for load compensation of an example of a thyristor converter of an input power source of an inverter circuit for driving an induction motor.
【０００２】[0002]
【従来の技術】インバータによる電動機駆動装置の入力
電流としてサイリスタコンバータの一例を図３に示す。
図３は従来例の要部構成とその制御方式を示すもので、
１は交流電源、２は電力変換器、３はリアクトル、４は
コンデンサ、５はインバータ回路、６は誘導電動機（以
下単に電動機という）である。また、７は電圧検出器、
８は電流検出器、９は電圧設定器、10ａ，10ｂは加減算
器、11は電圧制御器、12は電流制御器、13はゲート制御
器である。2. Description of the Related Art FIG. 3 shows an example of a thyristor converter as an input current of a motor drive device using an inverter.
FIG. 3 shows the configuration of the main part of the conventional example and its control system.
1 is an AC power supply, 2 is a power converter, 3 is a reactor, 4 is a capacitor, 5 is an inverter circuit, and 6 is an induction motor (hereinafter simply referred to as an electric motor). 7 is a voltage detector,
Reference numeral 8 is a current detector, 9 is a voltage setting device, 10a and 10b are addition / subtraction devices, 11 is a voltage controller, 12 is a current controller, and 13 is a gate controller.
【０００３】すなわち、図３に示す電力変換装置におい
ては、電力変換器２は交流電源１を直流電源に変換し、
インバータ回路５の供給電源となる。また、電力変換器
２は負荷側の電力すなわちインバータ回路５の電力の吸
収が必要となると、この負荷側からの電力を変換してそ
の回生電力の制御の機能を有する。リアクトル３および
コンデンサ４は電力変換器２出力の脈流分を平滑した直
流電源を提供する役割を果たす。インバータ回路５は、
直流を可変電圧・可変周波数の三相交流電源に変換する
ものであって、電動機６を駆動する。That is, in the power converter shown in FIG. 3, the power converter 2 converts the AC power supply 1 into a DC power supply,
It serves as a power supply for the inverter circuit 5. Further, when it is necessary to absorb the load side power, that is, the power of the inverter circuit 5, the power converter 2 has a function of converting the power from the load side and controlling the regenerated power thereof. The reactor 3 and the capacitor 4 play a role of providing a DC power source in which the pulsating current component of the output of the power converter 2 is smoothed. The inverter circuit 5 is
It converts direct current into a three-phase alternating current power source of variable voltage and variable frequency, and drives the electric motor 6.
【０００４】電圧検出器７は、インバータ回路５への供
給電圧を制御するための出力電圧ＶＤＣを得る。ＩＤＣ
は出力電流である。また、電流検出器８は電力変換器２
の入力電流ＩＡＣを得る。さて、加減算器10ａにて電圧
設定器９による電圧設定値に対して出力電圧ＶＤＣとの
差異が得られ、加減算器10ａより電圧制御器11の制御指
令が与えられ電圧制御器11から電流制御指令を出力す
る。ここで、電力変換器２の入力電流ＩＡＣと出力電流
ＩＤＣの関係は、次式にて表される。The voltage detector 7 obtains an output voltage VDC for controlling the voltage supplied to the inverter circuit 5. IDC
Is the output current. Further, the current detector 8 is the power converter 2
The input current IAC of Now, the adder / subtractor 10a obtains the difference from the output voltage VDC with respect to the voltage set value by the voltage setter 9, the adder / subtractor 10a gives a control command for the voltage controller 11, and the voltage controller 11 gives a current control command. Is output. Here, the relationship between the input current IAC and the output current IDC of the power converter 2 is represented by the following equation.
【０００５】 ＩＡＣ＝ 0.816ＩＤＣ ・・・・・・・・・・・・・・・・・（１）IAC = 0.816IDC (1)
【０００６】そして、電流検出器８出力の入力電流ＩＡ
Ｃを制御すべく、電圧制御器11出力の電流制御指令との
差異が加減算器10ｂにて得られ、この加減算器10ｂ出力
が電流制御器12の制御指令として与えられ、よってゲー
ト制御器13を介して電力変換器２の半導体スイッチであ
るサイリスタのゲート制御により、電流制御が行なわれ
る。また、電力変換器２の出力電流を直接的に検出して
これを制御する方法もあるが、式（１）にて示されるよ
うに等価であり、いずれを用いてもよい。The input current IA of the output of the current detector 8
In order to control C, the difference between the output of the voltage controller 11 and the current control command is obtained by the adder / subtractor 10b, and the output of this adder / subtractor 10b is given as the control command of the current controller 12, and therefore the gate controller 13 is activated. Through the gate control of a thyristor which is a semiconductor switch of the power converter 2, current control is performed. Also, there is a method of directly detecting the output current of the power converter 2 and controlling the output current, but it is equivalent as shown in the equation (1), and any of them may be used.
【０００７】[0007]
【発明が解決しようとする課題】しかしながら、この種
のものは、電動機６に対して急激な駆動・吸収の負荷変
動が発生した場合、電力変換器２と、リアクトル３およ
びコンデンサ４の平滑回路による制御応答の遅れによ
り、インバータ回路５の直流電圧は大きく変動するもの
となる。図４は電力変換器の出力電流と出力電圧の変動
の挙動推移を示し、ＩＤＣは出力電流、ＶＤＣは出力電
圧である。すなわち、電動機６の負荷が駆動・吸収に変
動すると、電力変換器２の出力電流ＩＤＣは大きく変動
し、これによって出力電圧ＶＤＣも大きく変動する。し
たがって、このような大きな電圧変動は、電動機のトル
クの変動，インバータ回路の駆動素子の破損，電力回生
時の転流失敗による過電流発生等の弊害をきたすことが
ある。However, in the case of this type, when a sudden driving / absorption load variation occurs in the electric motor 6, the smoothing circuit of the power converter 2, the reactor 3 and the capacitor 4 is used. Due to the delay of the control response, the DC voltage of the inverter circuit 5 changes greatly. FIG. 4 shows the behavior transition of the output current and the output voltage of the power converter, where IDC is the output current and VDC is the output voltage. That is, when the load of the electric motor 6 fluctuates to drive and absorb, the output current IDC of the power converter 2 fluctuates greatly, and the output voltage VDC also fluctuates greatly. Therefore, such a large voltage fluctuation may cause adverse effects such as fluctuation of the torque of the electric motor, damage to the drive element of the inverter circuit, and generation of overcurrent due to commutation failure during power regeneration.
【０００８】[0008]
【課題を解決するための手段】本発明は上述したような
点に鑑みなされたものであり、電動機の負荷変動はその
大きさに比例してインバータ回路の入力電流の大小に現
れ、すなわち電動機の負荷急変をそのままインバータ回
路の入力電流の急変としてとらえたものであって、この
電流を検出のうえ外乱観測器を介して電力変換器の電流
制御指令を補正することにより、インバータ回路の入力
電圧の変動を低減するよう構成したものである。さらに
は同様の発想より、平滑用コンデンサの電流も電動機の
負荷急変に伴って変動することに着眼し、このコンデン
サ電流を検出し同様に補償するよう構成してなるもので
ある。SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and the load fluctuation of the motor appears in the magnitude of the input current of the inverter circuit in proportion to the magnitude thereof, that is, in the motor. A sudden change in load is directly taken as a sudden change in the input current of the inverter circuit.By detecting this current and correcting the current control command of the power converter via the disturbance observer, the input voltage of the inverter circuit It is configured to reduce fluctuation. Further, based on the same idea, the current of the smoothing capacitor also changes in accordance with a sudden change in the load of the electric motor, and the capacitor current is detected and similarly compensated.
【０００９】[0009]
【作用】かかる解決手段の作用は、つぎに述べる実施例
において併せ詳述する。以下に、本発明を図面に基づい
てさらに詳細説明する。The operation of such a solution means will be described in detail in the following embodiments. Hereinafter, the present invention will be described in more detail with reference to the drawings.
【００１０】[0010]
【実施例】図１は本発明が適用された一実施例を図３に
類して表したもので、14は電流検出器、15は負荷補償
器、10ｃは加減算器である。なお、ここで電力変換器２
はサイリスタスイッチによる三相ブリッジの可逆回生方
式の例であるが、その半導体スイッチにトランジスタや
ＩＧＢＴ等を用いてなるものであってもよい。電流検出
器14は、インバータ回路２の直流電源電流を検出し、出
力電流ＩＤＣを検出して負荷補償器15に信号出力する。
この負荷補償器15出力が加減算器10ｃの一方の入力とし
て与えられ、他の入力として電圧制御器11出力が加減算
器10ｃに与えられている。さらに、その加減算器10ｃ出
力が加減算器10ｂに与えられる構成をなす。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an embodiment to which the present invention is applied, similar to FIG. 3, in which 14 is a current detector, 15 is a load compensator, and 10c is an adder / subtractor. In addition, here, the power converter 2
Is an example of a reversible regenerative system of a three-phase bridge using a thyristor switch, but a semiconductor switch using a transistor, an IGBT or the like may be used. The current detector 14 detects the DC power supply current of the inverter circuit 2, detects the output current IDC, and outputs a signal to the load compensator 15.
The output of the load compensator 15 is provided as one input of the adder / subtractor 10c, and the output of the voltage controller 11 is provided as the other input to the adder / subtractor 10c. Further, the output of the adder / subtractor 10c is provided to the adder / subtractor 10b.
【００１１】これより、加減算器10ａにて（ＶＳ−ＶＤ
Ｃ）を算出して電圧制御器11の入力信号とし、電流指令
値ＩＳ１を得る。加減算器10ｃにて電流指令値ＩＳ１に
対して負荷補償器15出力による補正が加えられ、電流指
令値ＩＳ２が得られる。加減算器10ｂにて（ＩＳ２−Ｉ
ＡＣ）を算出し、電流制御器12の制御指令信号が得られ
るものである。From this, in the adder / subtractor 10a (VS-VD
C) is calculated and used as the input signal of the voltage controller 11, and the current command value IS1 is obtained. The current command value IS1 is corrected by the adder / subtractor 10c by the output of the load compensator 15 to obtain the current command value IS2. In the adder / subtractor 10b (IS2-I
AC) is calculated and a control command signal for the current controller 12 is obtained.
【００１２】そして、電動機負荷が変動すると、インバ
ータ回路の直流電源の電流が変動して電圧が変動する。
その電圧の変動を低減するため電圧制御器11が作動し出
力電圧ＶＤＣが一定になるよう制御されるが、電動機負
荷の急変に対して制御応答が追従できない点を、つぎの
ように解消し得る。ここで負荷補償器15は、次式（２）
または式（３）で表される関数にて構成される。When the motor load fluctuates, the current of the DC power source of the inverter circuit fluctuates and the voltage fluctuates.
In order to reduce the fluctuation of the voltage, the voltage controller 11 is operated to control the output voltage VDC to be constant, but the point that the control response cannot follow the sudden change of the motor load can be solved as follows. . Here, the load compensator 15 has the following equation (2).
Alternatively, it is configured by the function represented by the equation (3).
【００１３】 （１＋ＴＤ・ｓ）／（１＋ＴＩ・ｓ） ・・・・・・・・・・・・（２） （ＴＤ・ｓ）／（１＋ＴＩ・ｓ） ・・・・・・・・・・・・（３）(1 + TD · s) / (1 + TI · s) ······ (2) (TD · s) / (1 + TI · s) ···・ ・ (3)
【００１４】すなわち、式（２），（３）における関数
の分母（１＋ＴＩ・ｓ）は制御補償上の高周波数領域の
外乱入力および高周波脈動を除去する目的で設計される
ものであり、関数の分子（１＋ＴＤ・ｓ）または分子
（ＴＤ・ｓ）は電流制御の一次位相進み制御の目的とし
て設計されるものである。ここで、ＴＤとＴＩの関係は
（ＴＤ＞ＴＩ）となるよう設計される。かようにして、
インバータ回路２の入力電流の変動を負荷補償器15にお
ける関数関係にてとられ、その補償出力を電流制御器12
の制御指令に補償を加えることにより、電圧制御におけ
る負荷変動に対する制御対応を改善し、電圧変動を低減
できる。これを、出力電流ＩＤＣと出力電圧ＶＤＣの挙
動として図４に類して表すと、図２のように示されるも
のとなる。That is, the denominator (1 + TI · s) of the function in the equations (2) and (3) is designed for the purpose of removing the disturbance input and the high frequency pulsation in the high frequency region on the control compensation, and The numerator (1 + TD · s) or the molecule (TD · s) is designed for the purpose of the primary phase advance control of current control. Here, the relationship between TD and TI is designed to be (TD> TI). In this way,
The fluctuation of the input current of the inverter circuit 2 is taken by the functional relation in the load compensator 15, and the compensation output is taken as the current controller 12
By adding the compensation to the control command, the control response to the load fluctuation in the voltage control can be improved and the voltage fluctuation can be reduced. If this is expressed as a behavior of the output current IDC and the output voltage VDC in a manner similar to FIG. 4, it becomes as shown in FIG.
【００１５】さらには、本実施例はつぎの如く作用し得
る。一般に、サイリスタコンバータはこの装置自体に出
力電流の制御機能を有している。しかしながら、リアク
トル３およびコンデンサ４によって負荷電流の変動が平
滑され、急激な負荷電流の変動に追従して制御し難た
い。ここで、前述の関数にて前向きに進み補償を外乱オ
ブザーバとして、電力変換器２の電源制御指令に印加す
ることで、インバータ回路の入力電流すなわち電動機の
負荷変動に対して、電力変換器によるコンデンサの電圧
の変動を少なくすべく制御することが可能となる。な
お、電流検出器14に代え、コンデンサ４の電流を得るよ
うにすることでも、また同様に作用し得ることは明らか
である。Furthermore, this embodiment can operate as follows. Generally, the thyristor converter has a control function of the output current in the device itself. However, the reactor 3 and the capacitor 4 smooth the fluctuations in the load current, and it is difficult to control the rapid fluctuations in the load current. Here, by applying forward compensation in the function described above as a disturbance observer to the power supply control command of the power converter 2, the capacitor by the power converter responds to the input current of the inverter circuit, that is, the load change of the motor. It is possible to control so as to reduce the fluctuation of the voltage. Obviously, instead of the current detector 14, the current of the capacitor 4 can be obtained, and the same effect can be obtained.
【００１６】[0016]
【発明の効果】以上説明したように本発明によれば、イ
ンバータ回路の入力電源の電圧変動を格別に低減し得る
簡便な装置を提供できるとともに、インバータ回路によ
る安定運転を実現しかつ過電圧によるインバータ回路破
損を防止できる。As described above, according to the present invention, it is possible to provide a simple device capable of significantly reducing the voltage fluctuation of the input power source of the inverter circuit, and to realize stable operation by the inverter circuit and the inverter due to overvoltage. Circuit damage can be prevented.
【図１】図１は本発明の一実施例の要部構成を示す制御
ブロック図である。FIG. 1 is a control block diagram showing a main part configuration of an embodiment of the present invention.
【図２】図２は図１による電力変換器の出力電流と出力
電圧の変動の挙動推移を示す図である。FIG. 2 is a diagram showing a behavior transition of a change in output current and output voltage of the power converter according to FIG.
【図３】図３は従来例を示す制御ブロック図である。FIG. 3 is a control block diagram showing a conventional example.
【図４】図４は図３による電力変換器の出力電流と出力
電圧の変動の挙動推移を示す図である。FIG. 4 is a diagram showing a behavior transition of fluctuations in output current and output voltage of the power converter according to FIG. 3.
１ 交流電源 ２ 電力変換器 ３ リアクトル ４ コンデンサ ５ インバータ回路 ６ 誘導電動機（電動機） ７ 電圧検出器 ８ 電流検出器 ９ 電圧設定器 11 電圧制御器 12 電流制御器 13 ゲート制御器 14 電流検出器 15 負荷補償器 1 AC power supply 2 Power converter 3 Reactor 4 Capacitor 5 Inverter circuit 6 Induction motor (motor) 7 Voltage detector 8 Current detector 9 Voltage setting device 11 Voltage controller 12 Current controller 13 Gate controller 14 Current detector 15 Load Compensator
Claims (2)
て電動機駆動装置に電力を供給し、あるいは電動機負荷
より動力を吸収し交流電源に電力を返還する半導体電力
変換装置の直流電圧制御にてマイナーループに電流制御
系を有する電力変換装置の電圧制御装置において、直流
出力電流に相当する信号を検出するとともに、電動機負
荷急変の際の電流変化に至る伝達関数の逆関数に相当す
る外乱を観測する手段を備え、該手段を介して前記電流
制御系の入力信号回路に負フィードバックすることを特
徴とする電力変換装置の電圧制御装置。1. A direct current voltage control for a semiconductor power conversion device for converting an alternating current power source into a direct current and supplying power to a motor driving device through a smoothing circuit, or absorbing power from a motor load and returning the power to the alternating current power source. In a voltage control device of a power conversion device having a current control system in a minor loop, a signal corresponding to a DC output current is detected, and a disturbance equivalent to an inverse function of a transfer function leading to a current change at the time of a sudden load change of a motor is detected. A voltage control device for a power conversion device, comprising: a means for observing, and performing negative feedback to an input signal circuit of the current control system via the means.
のコンデンサ電流に相当する信号を用いるようにした請
求項１記載の電力変換装置の電圧制御装置。2. The voltage control device for a power converter according to claim 1, wherein a signal corresponding to a capacitor current of the smoothing circuit is used instead of the DC output current.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP09921594A JP3392939B2 (en) | 1994-04-12 | 1994-04-12 | Voltage converter for power converter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP09921594A JP3392939B2 (en) | 1994-04-12 | 1994-04-12 | Voltage converter for power converter |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH07288980A true JPH07288980A (en) | 1995-10-31 |
| JP3392939B2 JP3392939B2 (en) | 2003-03-31 |
Family
ID=14241439
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP09921594A Expired - Fee Related JP3392939B2 (en) | 1994-04-12 | 1994-04-12 | Voltage converter for power converter |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3392939B2 (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005051898A (en) * | 2003-07-31 | 2005-02-24 | Toyota Motor Corp | Voltage conversion device and computer-readable recording medium with program stored thereon for making computer control voltage conversion |
| WO2014125594A1 (en) * | 2013-02-14 | 2014-08-21 | 東芝三菱電機産業システム株式会社 | Power-conversion device and method for controlling same |
| WO2014125595A1 (en) * | 2013-02-14 | 2014-08-21 | 東芝三菱電機産業システム株式会社 | Thyristor startup device and method for controlling same |
| CN115664265A (en) * | 2022-09-28 | 2023-01-31 | 西安爱科赛博电气股份有限公司 | Control method for inhibiting motor cluster load current fluctuation |
-
1994
- 1994-04-12 JP JP09921594A patent/JP3392939B2/en not_active Expired - Fee Related
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005051898A (en) * | 2003-07-31 | 2005-02-24 | Toyota Motor Corp | Voltage conversion device and computer-readable recording medium with program stored thereon for making computer control voltage conversion |
| US7355869B2 (en) | 2003-07-31 | 2008-04-08 | Toyota Jidosha Kabushiki Kaisha | Voltage conversion device and computer-readable recording medium having program recorded thereon for computer to control voltage conversion |
| WO2014125594A1 (en) * | 2013-02-14 | 2014-08-21 | 東芝三菱電機産業システム株式会社 | Power-conversion device and method for controlling same |
| WO2014125595A1 (en) * | 2013-02-14 | 2014-08-21 | 東芝三菱電機産業システム株式会社 | Thyristor startup device and method for controlling same |
| JP6010212B2 (en) * | 2013-02-14 | 2016-10-19 | 東芝三菱電機産業システム株式会社 | Power converter and control method thereof |
| JPWO2014125595A1 (en) * | 2013-02-14 | 2017-02-02 | 東芝三菱電機産業システム株式会社 | Thyristor starter and control method thereof |
| US9912259B2 (en) | 2013-02-14 | 2018-03-06 | Toshiba Mitsubishi-Electric Industrial Systems Corporation | Thyristor starting device and control method therefor |
| CN115664265A (en) * | 2022-09-28 | 2023-01-31 | 西安爱科赛博电气股份有限公司 | Control method for inhibiting motor cluster load current fluctuation |
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|---|---|
| JP3392939B2 (en) | 2003-03-31 |
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