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 inserts a damping resistance in resonance circuit, is proposed. Firstly using the participation factor of state equation and condenser capacitance, the condenser current is defined. And, the damping resistance position becomes the maximum current condenser. Then, to determine the damping resistance value, a natural frequency characteristic to current amplification degree is introduced using with eigen value. Finally, adopting numerical examination, it is known that the damping resistance is effective in any case. Moreover, the hybrid method of the damping resistance and the optimal harmonic source point method is more effective in multi resonance circuits problem.
