| 摘要 |
PURPOSE:To restrain affection for a PWM carrier and obtain the effect of a filter at the natural resonance point of a line by a method wherein a LRC series tuning filter is connected between a voltage type PWM inverter and a load so as to be in parallel to the load while a reactance is connected in series to the load and the series tuning filter. CONSTITUTION:A LRC series tuning filter 3 is provided in parallel to a load 2 whereby tuning resonance higher harmonics to the load 2 absorbed by the filter. Further, a reactance As is provided in series to the load 2 and the series tuning filter 3 whereby peak voltage restraining effect is improved by a tuning current. A serge peak voltage, induced by the rectangular pulse of a voltage type PWM inverter 1 due to the resonance of a line, may be restrained effectively in such a manner whereby the serge voltage may be restrained so as to be lower than a corona voltage and the affection of the voltage of the load instruments 2 to the life of insulation of the same may be reduced. |
