POWER CONVERSION APPARATUS

• Main Author: IWABORI MICHIO
• Format: Patent
• Language: English; Japanese
• Published: 19.01.2017
• Subjects: APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC,OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWERSUPPLY SYSTEMS; CONTROL OR REGULATION THEREOF; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUTPOWER; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; ELECTRICITY; GENERATION

PROBLEM TO BE SOLVED: To provide a power conversion apparatus which supplies a line-to-line voltage with no distortion to a three-phase AC load by reducing a 3m-th harmonic wave component without using a complicated control block.SOLUTION: In the power conversion apparatus, bypass switches are connected between output terminals of single-phase output cells which are connected in series for each phase. When all the cells are sound, all the switches are turned off and an AC output voltage of each phase is controlled to be a first AC voltage for which the 3m-th harmonic wave component ((m) is a natural number) is superposed on a fundamental wave component. If a single-phase output cell belonging to a first phase circuit is broken down, a switch between the output terminals of that cell is turned on and when outputting a line-to-line voltage equal to or higher than a predetermined value, output voltages of second and third phase circuits are controlled to be a voltage for which the first AC voltage and a second AC voltage are added, a phase of at least one of the first and second AC voltages being different from that of the fundamental wave component, magnitudes of both the voltages being equal and a phase difference therebetween being an electric angle 60°.SELECTED DRAWING: Figure 1 【課題】複雑な制御ブロックを用いずに、第３ｍ次調波成分を低減して歪みのない線間電圧を三相交流負荷に供給する電力変換装置を提供する。【解決手段】相ごとに直列接続された単相出力セルの出力端子間にバイパス用のスイッチが接続され、全てのセルの健全時に全てのスイッチをオフし、各相の交流出力電圧が基本波成分に第３ｍ次調波成分（ｍ：自然数）を重畳した第１の交流電圧になるように制御される電力変換装置において、第１の相回路に属する単相出力セルが故障した時に、そのセルの出力端子間のスイッチをオンすると共に、所定値以上の線間電圧を出力させる場合に、第２，第３の相回路の出力電圧が、第１の交流電圧と、その基本波成分に対して少なくとも一方の位相が異なり、かつ両者の大きさが等しく、互いの位相差が電気角６０°となる第２の交流電圧と、を加算した電圧となるように制御する。【選択図】図１