| 摘要 |
PURPOSE:To prevent the abrupt change of the output power of an inverter at the switching time between output constant-voltage control and output constant-power control by providing a control means which controls the output fluctuation of the inverter at the switching time between the output constant-voltage control and output constant-power control. CONSTITUTION:When a linkage operation command is inputted to an inverter, an analog switch 19 is turned on and transformers 9 and 10 respectively detect the output voltage of an inverter and the voltage of a power system. Then a phase detector 11 detects the phase difference between both voltages and inputs the detected phase difference to a frequency adjuster 21. The output voltage of the inverter is controlled so that the phase of the output voltage can be synchronized to that of the voltage of the power system and, after a circuit breaker 8 is incorporated upon completing the synchronization, a rate-of-change limiter 14 inputs the output power of the inverter and a power deviation signal to a high-value selector 18 and, at the same time, an analog switch 17 is turned on so that the signal of an initial phase setter 16 can be inputted to the selector 18. Immediately after incorporating the breaker 8, a phase signal, the signal of the setter 16, and an output frequency command 20 are inputted to the adjuster 21 and phase control is performed. As a result, the output power of the inverter can be controlled without allowing the abrupt change of the output power. |
