抄録
There are many PWM control apparatuses, which are higher harmonics current sources, in distribution systems. And higher harmonics causes over current by parallel resonance. To avoid the over current, it is necessary to suppress the resonance.
In this paper, a new suppression method, which uses the effect of source connected point in resonance circuit, is proposed. Firstly it shows that the optimal point, which gives a minimum current amplification degree, is orthogonal to static condenser voltage. And then, using eigenvector of state equation, the participation factor is defined. When the participation factor is zero, the orthogonal condition is introduced. Therefore the optimal point is given by using with the participation factor. Finally, adopting numerical examination, it is known that multiple optimal points usually exist. Therefore, we can choose the advantageous point as a source connected node.
