摘要 |
<P>PROBLEM TO BE SOLVED: To provide a single-phase voltage AC/DC converter which enables self-regulative parallel operation in which a plurality of parallelly connected devices operating in parallel at a single-phase alternating current individually controls output deflection in a self-regulative manner, and surely detects standalone operation when a power system fails. <P>SOLUTION: A single-phase alternating current having a given phase difference from the phase of a single-phase AC output voltage from an AC terminal is generated, and PWM control over an inverter is carried out using the generated single-phase alternating current and the single-phase AC output voltage from the AC terminal. The single-phase alternating current having a given phase difference from the phase of the single-phase AC output voltage from the AC terminal is positively fed back. When a standalone operation occurs, the standalone operation is detected using the resulting automatic fluctuation of an output frequency, to prevent the operation. <P>COPYRIGHT: (C)2010,JPO&INPIT |