| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent an AC power supply side from having a leading power factor due to an LC filter on the AC power supply side. <P>SOLUTION: In power factor control where the input power factor is sustained at "1" by a controller 4 performing PWM control of each two-way switch by inserting an AC-AC direct conversion circuit 3 constituted of an input LC filter 2 and a two-way switch into each phase of an AC power supply 1, a power factor compensation circuit 5 determines the compensation value of filter lead component of power supply voltage Vs by means of a coefficient unit 5A having the filter constants as coefficients and corrects a power supply current command value Isref by the product of the power supply voltage Vs and the compensation value to obtain an input current command Ismcref. It also include to estimate an input current command value, to estimate a power conversion efficiency, and the like, and to take account of the inductance of the AC power supply in the filter constant. <P>COPYRIGHT: (C)2008,JPO&INPIT |
