| 摘要 |
<P>PROBLEM TO BE SOLVED: To determine an accurate phase of a supply voltage. <P>SOLUTION: A power conversion device includes: a converter circuit (2) for full-wave-rectifying a supply voltage (V<SB POS="POST">in</SB>) of a single phase AC power supply (6); a DC link section (3) having a capacitor (3a) and outputting a pulsating DC voltage (V<SB POS="POST">dc</SB>); an inverter circuit (4) for switching and converting the DC voltage (V<SB POS="POST">dc</SB>) output from the DC link section (3) into AC; and a phase estimation section (70) for estimating an estimated power supply phase (θ<SB POS="POST">in</SB>) from the period of the waveform of the DC voltage (V<SB POS="POST">dc</SB>), calculating a phase shift between the estimated power supply phase (θ<SB POS="POST">in</SB>) and the phase of the DC voltage (V<SB POS="POST">dc</SB>), and outputting as a phase of the supply voltage (V<SB POS="POST">in</SB>) a value of the estimated power supply phase (θ<SB POS="POST">in</SB>) corrected in accordance with the phase shift. <P>COPYRIGHT: (C)2012,JPO&INPIT |
