Pulse-Resistive Neutral Grounding of Three-Phase Power Network and its Physical Model

A method of pulse high-resistance neutral grounding has been developed for power distribution networks. The grounding of the neutral grounding resistor occurs with intermittent ground faults when the neutral-to-ground voltage derivative (duN/dt) is high enough. The vast majority parameters of power networks are such that the voltage derivative at permanent earth fault (duN~/dt) is much less than at restriking one (i.e. duN/dt
_max
>>duN~/dt). It allows effectively controlling resistive grounding mode of the network neutral and eliminating direct resistive grounding disadvantages caused by the increased fault current of the industrial frequency. The pulse resistive grounding efficiency is theoretically proved. A low-voltage physical model of power network with different methods of neutral grounding including pulse-resistive one is designed and manufactured.