Novel control techniques of Petersen-coil

Most Chinese medium voltage (MV) power systems have been operated with neutral resonance grounded. The resonance grounding method is hard to completely satisfy the requirement of suppressing normal neutral-to-ground voltage and self-extinguishing arc grounding faults in distribution network with high asymmetry, where Peterson-coil automatic tuning is also difficult to be implemented. In order to improve them, some novel control techniques of Petersen-coil are proposed in the paper. They include a new grounding method based on Petersen-coil in parallel with a reactor, a novel method for measuring insulation parameters to ground, and a novel control strategy of Petersen-coil. Dynamic power system experimentations are carried out. Experimentation results show that the proposed neutral grounding method can restrain normal voltage of neutral point and ensure arc grounding fault self-extinguished, the proposed measurement method of insulation parameters is simple, convenient, precise and tested in real time without power supply interrupting.