| 摘要 |
PROBLEM TO BE SOLVED: To stably restart a voltage-type self-excited power conversion apparatus after the apparatus has been stopped temporarily by a method wherein, when a DC voltage becomes a rated voltage or lower, electric power is accommodated to a DC capacitor from a charger via a reverse-current prevention diode and the DC voltage is maintained at a rated DC voltage. SOLUTION: A series circuit which is composed of a reverse-current prevention diode and of a charger 10 provided with a battery 10A and with a current- limiting resistance 10B is connected in parallel with a DC capacitor 5 which is connected across DC terminals of a power converter 2. Then, when the power converter 2 is stopped temporarily due to a reduction in the control amount of effective power or reactive power or due to the abnormality of an AC system 1 so as to drop the voltage of the DC capacitor 5, electric power is accommodated to the DC capacitor 5 from the charger 10, and a voltage is maintained at a DC rated voltage which is required to operate the power converter 2. Thereby, the power converter 2 is set to a state that it can be always restarted, and the linkage operation of the AC system 1 with the power converter 2 can be performed smoothly. |
