| 摘要 |
PROBLEM TO BE SOLVED: To provide a synchronization detecting apparatus such that single phase AC voltage is not differentiated directly, impact of high-frequency components is suppressed, and cases of dividing by zero is eliminated and results in less likely of becoming unstable. SOLUTION: The synchronization detecting apparatus 130 includes a standard angular frequency ω<SB>co</SB>; a sampler 133 detecting test voltage waveform of a test single phase AC voltage source 12; a delay circuit 134 generating a delay voltage waveform, delaying the time larger than (m-1)π/ω<SB>co</SB>and smaller than mπ/ω<SB>co</SB>(m is a natural number) for the test voltage waveform detected by the sampler 133; and an calculating section 135 calculating frequency difference cosine signal and frequency difference sine signal, by taking the difference between the test angular frequency ω<SB>s</SB>and the test standard angular frequency ω as the angular frequency, based on the test voltage waveform detected by the sampler 133; the delay voltage waveform generated by the delay circuit 134; and a test standard angular frequency ω of a given test standard single-phase AC voltage source 11. COPYRIGHT: (C)2011,JPO&INPIT |
