Study Of The Resonance Overvoltage In 35kV Small Current Grounding System

With the development of power equipment, people required for the higher quality of power supply, improve the stability of power grid operation, improve the quality of power supply is one of the big power research direction. Of distribution network in our country mainly adopts hierarchy, in 35 kV power supply system, a greater influence on the overvoltage in power system, for a long time, when the system resonance occurs, the system capacitance oscillator circuit, high amplitude ferroresonance overvoltage. Because of the complexity of the power supply system structure and operation flexibility,The phenomenon of Overvoltage is become a threat to the safe operation of the power supply system of industrial and mining enterprises of important reasons。In this paper, First elaborates the research situation at home and abroad and the commonly used harmonic elimination measures,and illustrates the research significance of ferroresonance overvoltage,and analyzed the principle of ferromagnetic resonance、resonance condition 、restrain conditions and hazards. Take an example of mine of 35 kv power supply system of ferroresonance overvoltage. First analyzed the structure and operation mode of the power supply circuit,and has carried on the appear overvoltage Situation preliminary analysis,finally according to the 35 KV power supply line in the MATLAB establishment the model and simulation,is not power frequency or high frequency ferromagnetic resonance.,harmonic elimination scheme of ferroresonance 35 kV system is proposed, and put them into practice field running proves that the theoretical analysis, simulation and harmonic elimination scheme is correct and reasonable. Under the lightning produce resonance overvoltage phenomena are simulated.