Patent ID: 7400116

Claim:
A power generating system using a stationary gas turbine engine as a power source, the power generating system including a pre-charging system for a smoothing capacitor, the pre-charging system comprising: an AC power source for driving of the power generating system at a time of starting operation of the power generating system; a switching circuit connected to the AC power source; a smoothing capacitor connected in parallel to the switching circuit; a main contactor disposed between the AC power source and the switching circuit; an LC filter disposed between the main contactor and the switching circuit; a pre-charging contactor connected between the AC power source and the switching circuit in parallel to the main contactor; a voltage detecting means for detecting a voltage of the smoothing capacitor; and a control means for controlling charging of the smoothing capacitor, wherein the pre-charging system is configured to charge the smoothing capacitor to have a predetermined voltage, and in order for the smoothing capacitor to be charged to have said predetermined voltage before starting operation of the power generating system, the control means turns on the pre-charging contactor to charge the smoothing capacitor through the switching circuit by the AC power source; and, when the voltage of the smoothing capacitor detected by the voltage detecting means exceeds a predetermined intermediate value, brings the switching circuit into a boosting operation with a command from the control means to further charge the smoothing capacitor.