POWER CONVERSION DEVICE AND CONTROL METHOD THEREOF

• Main Authors: KAGEYAMA TAKAHISA, KOYAMA YUJI, HASEGAWA RYUTA, FUJITA TAKASHI
• Format: Patent
• Language: English; Japanese
• Published: 24.10.2019
• 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

To suppress an increase in capacitor capacity while suppressing a change in a neutral point potential in a wider operation region.SOLUTION: A power conversion device according to an embodiment includes a neutral point clamp type power converter, and control means for controlling the neutral point potential fluctuation of the power converter by calculating a zero phase voltage of the power converter by using a predetermined calculation formula, and superimposing the zero phase voltage on the voltage command value of each phase, and when there is a voltage command value whose sign changes due to the superposition of the zero phase voltage, the control means reverses the sign of the voltage command value and recalculates the zero phase voltage, and superimposes the zero phase voltage after recalculation on the voltage command value of each phase.SELECTED DRAWING: Figure 3 【課題】 より広い動作領域で中性点電位の変動を抑制し、コンデンサ容量の増加を防ぐことを可能にする。【解決手段】 実施形態の電力変換装置は、中性点クランプ型の電力変換器と、前記電力変換器の零相電圧を所定の計算式を用いて計算し、当該零相電圧を各相の電圧指令値に重畳することで前記電力変換器の中性点電位の変動を抑制する制御を行う制御手段とを具備し、前記制御手段は、前記零相電圧の重畳によって符号が変化する電圧指令値がある場合、当該電圧指令値の符号を反転させて前記零相電圧の再計算を行い、再計算後の零相電圧を各相の電圧指令値に重畳する。【選択図】図３