POWER CONVERSION DEVICE, POWER SUPPLY SYSTEM, AND METHOD FOR CONTROLLING POWER CONVERSION DEVICE

• Main Authors: OKUMURA TOSHIAKI, AYAI NAOKI
• Format: Patent
• Language: English; Japanese
• Published: 21.05.2020
• 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; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTINGELECTRIC POWER; CONTROL OR REGULATION THEREOF; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUTPOWER; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; ELECTRICITY; GENERATION; SYSTEMS FOR STORING ELECTRIC ENERGY

To suppress mutual interference between isolated operation detection and voltage fluctuation suppression while avoiding stoppage of a power conversion device.SOLUTION: A power conversion device system-interconnected with a commercial power system is provided between an AC electric path connected to the commercial power system and a DC power supply, and comprises: a power conversion section for power-converting from DC to AC or vice versa; and a control section including a first calculation section for controlling switching operation of the power conversion section, and obtaining a first reactive power to be injected for isolated operation detection on the basis of AC voltage of the AC electric path, and a second calculation section for obtaining active power and a second reactive power for suppressing voltage fluctuation of the AC electric path. When the first calculation section attempts to inject the first reactive power which interferes with the second reactive power, the control section injects the first reactive power in a state in which a present value of the second reactive power is kept constant.SELECTED DRAWING: Figure 2 【課題】電力変換装置の停止を回避しつつ、単独運転検出と電圧変動抑制との相互干渉を抑制する。【解決手段】商用電力系統と系統連系する電力変換装置であって、商用電力系統に繋がる交流電路と直流電源との間に設けられ、直流から交流又はその逆の電力変換を行う電力変換部と、電力変換部のスイッチング動作を制御し、交流電路の交流電圧に基づいて、単独運転検出用に注入すべき第１の無効電力を求める第１演算部、及び、交流電路の電圧変動抑制用の有効電力及び第２の無効電力を求める第２演算部を含む制御部と、を備え、第１演算部が第２の無効電力と干渉する第１の無効電力を注入しようとするとき、制御部は、第２の無効電力の現在値を一定に保持した状態で第１の無効電力を注入する、電力変換装置である。【選択図】図２