| 摘要 |
PURPOSE:To reduce reactive power and harmonic currents by combining a separately exciting converter which is controlled within the delaying power-factor range, a self-exciting converter which is controlled within the gaining power-factor range, and a self-exciting converter whose power factor is 1 or nearly equal to 1. CONSTITUTION:An AC-power-supply system 1 is connected to a power converter comprising a separately exciting converter 31 which is controlled within the delaying power-factor range, a self-exciting converter 32 which is controlled within the gaining power-factor range, and a self-exciting converter 33 which is controlled so that the power factor becomes 1 or nealy equal to 1, and supplies power to loads 41, 42, and 43. Since one self-exciting converter is controlled to yield the gaining reactive power which is used to compensate the delaying reactive power caused by the separately exciting converter, and the other self-exciting conveter is controlled to yield a power factor of 1, the reactive power becomes zero or nearly equal to zero, and the power-supply current is overlapped on the asymmetrical control current with the power factor being 1, thereby the harmonic current can be greatly reduced. |
