Patent ID: 7332894

Claim:
A power generation apparatus comprising: an AC energization synchronous generator; switching means for connecting to a network disposed on a stator side of said AC energization synchronous generator; energizing means connected to a secondary winding of said AC energization synchronous generator for applying a variable frequency AC; control means for controlling said switching means and said energizing means; means for detecting a network side voltage of said switching means; and means for detecting a voltage of said switching means on a stator side, wherein the power generation apparatus further comprises means for calculating a slip frequency of said AC energization synchronous generator from a frequency of a stator side voltage generated by energizing a secondary side of said AC energization synchronous generator at a predetermined frequency, a frequency of a network voltage obtained from a network voltage detection value and a secondary side excitation frequency and making the secondary side excitation frequency be coincident with the calculated slip frequency, while said switching means is open.