Practical Research On Fault Location In Distribution Networks

Ferromagnetic resonance and very low frequencies oscillations caused by saturated Electromagnetic Voltage Transformers often occur in the system neutral point isolated. Theycan endanger the voltage stability and safety of electric equipments.This paper analyzes the principle and the condition of resonance and obtains the rule which the resonance occurs ;The approximated analysis and simulation law have been carried on separately in single-phase and three-phase ferromagnetic resonance electric circuit.In this paper,two kinds of harmony measures( non-ohmic resistor or against resonant PT on PT neutral point)have been theoretically analysed and one the brand new harmony measure is proposed.This paper uses separately the partition linearization and the vector graphic methodand the compensation principle to carry on the value simulation and the compution analysis and prove all kinds of measurements to be feasibile.Last,though simulation caculaion by ATP ,the paper discussed and comprehensively compared with all kinds of eliminations which restrain those overvoltage and proposed the effective measurements of solving its insufficiency.