JPH1054852A5

JPH1054852A5 -

Info

Publication number: JPH1054852A5
Application number: JP1996227509A
Authority: JP
Filing date: 1996-08-09
Publication date: 2005-03-17
Anticipated expiration: 2016-08-09

Description

【発明の名称】インバータ装置 [Name of invention] Inverter device

【０００８】
【課題を解決するための手段】
上記課題を解決するため、直列接続した半導体スイッチング素子をオンオフ制御し、直流電圧を３相交流電圧に変換出力するインバータ装置において、３相全ての前記各下段側半導体スイッチング素子と前記直流電圧の負極側との間に接続された３個の各電流検出用抵抗と、前記３個の各電流検出用抵抗に基づいて得られる各相電流検出値のうち、電流検出値として用いる２相をインバータ装置の動作制御中に順次切替選択していく電流検出相切替手段を備えたことを特徴としている。
また、前記インバータ装置において、前記電流検出相切替手段が選択した２相の各電流検出値を、各々につき当該相の下段側半導体スイッチング素子へのオン指令期間中に検出する電流検出タイミング手段を備えたことを特徴としている。
さらには、前記電流検出タイミング手段は、選択した２相の電流検出を近接して行ない、その時間差は半導体スイッチング素子のスイッチング周期よりも短いものであることを特徴としている。
さらにまた、前記電流検出タイミング手段は、先に中間電圧相の電流検出を行うことを特徴としている。
また、前記各インバータ装置において、前記電流検出相切替手段は、出力電圧指令の電圧位相に基づいて電流検出値として用いる２相を選択することを特徴としている。
あるいは、前記電流検出相切替手段は、出力電圧指令値に基づいて電流検出値として用いる２相を選択することを特徴としている。
あるいは、前記電流検出相切替手段は、前記下段側半導体スイッチング素子のオフ指令時間に基づいて電流検出値として用いる２相を選択することを特徴としている。 [0008]
[Means for solving the problem]
In order to solve the above problems, an inverter device that controls the on/off of semiconductor switching elements connected in series and converts a DC voltage into a three-phase AC voltage and outputs the voltage is characterized by comprising three current detection resistors connected between each of the lower-stage semiconductor switching elements of all three phases and the negative pole of the DC voltage, and current detection phase switching means that sequentially selects two phases to be used as current detection values from the phase current detection values obtained based on the three current detection resistors during operation control of the inverter device.
The inverter device is also characterized by comprising a current detection timing means for detecting each current detection value of the two phases selected by the current detection phase switching means during an ON command period for the lower-stage semiconductor switching element of the corresponding phase.
Furthermore, the current detection timing means detects the currents of the selected two phases closely, and the time difference therebetween is shorter than the switching period of the semiconductor switching elements.
Furthermore, the current detection timing means is characterized in that it first detects the current of the intermediate voltage phase.
In each of the inverter devices, the current detection phase switching means selects two phases to be used as the current detection value based on the voltage phase of the output voltage command.
Alternatively, the current detection phase switching means may select two phases to be used as the current detection value based on the output voltage command value.
Alternatively, the current detection phase switching means selects two phases to be used as the current detection value based on an OFF command time of the lower-stage semiconductor switching element.

Claims

An inverter device that controls the on/off of semiconductor switching elements connected in series to convert DC voltage into three-phase AC voltage and output the voltage,
three current detection resistors connected between the lower-stage semiconductor switching elements of all three phases and the negative pole of the DC voltage;
An inverter device characterized by comprising a current detection phase switching means for sequentially selecting two phases to be used as current detection values from among the phase current detection values obtained based on the three current detection resistors during operation control of the inverter device.

2. The inverter device according to claim 1, further comprising current detection timing means for detecting each current detection value of the two phases selected by the current detection phase switching means during a period when an ON command is issued to a lower-stage semiconductor switching element of the corresponding phase.

3. The inverter device according to claim 2, wherein said current detection timing means detects the currents of the selected two phases closely with a time difference shorter than the switching period of the semiconductor switching elements.

4. The inverter device according to claim 3, wherein the current detection timing means detects the current of the intermediate voltage phase first.

5. The inverter device according to claim 1, wherein the current detection phase switching means selects two phases to be used as the current detection value based on the voltage phase of the output voltage command.

5. The inverter device according to claim 1, wherein the current detection phase switching means selects two phases to be used as the current detection value based on an output voltage command value.

5. The inverter device according to claim 1, wherein the current detection phase switching means selects two phases to be used as the current detection value based on an OFF command time of the lower-stage semiconductor switching element.