The Research of High-Voltage Auxiliary Power System Neutral Point Grounding Modes Between the Nuclear Power Plant and Conventional Fossil Fuel Power Plant

Abstract

Having induced the grounding modes of the high-voltage auxiliary power system neutral point in the large-scale nuclear power plant and the conventional fossil fuel power plant, having analyzed determining principles, commonly used grounding modes, requirements of related codes, determining methods of the neutral point grounding modes, having done the research of nuclear power plant and conventional fossil fuel power plant auxiliary power system’s different characteristics leading to different demands of the grounding modes, and having done the research of the main nuclear power plants and the partial fossil fuel power plants high-voltage auxiliary power system neutral point grounding modes’ selection and calculation with the practical engineerings, also having put forward optimal design schemes, at last, a conclusion works out: high-voltage auxiliary power system neutral point grounding modes directly affect the running of the auxiliary power system and even affect the security of the nuclear safety and the operation of the power plant. First, choose the suitable grounding mode according to the calculation result of capacitive current. Then, choose more conducive grounding mode to the operation of power plant according to the operation of technology equipments, the power requirement from the configuration, the connection of auxiliary power, and the cut from the accident of auxiliary power. I hope this article can play a role for reference on the selection of the auxiliary power system grounding modes. Currently, in power plants, the application of the extinction coil in high-voltage auxiliary power system neutral point is less experienced. As some power plants which are under-construction will be putting into operation one after another, a whole set of perfect security arrangements and operating experiences will also be accumulated inevitably.