Research On Suppression Of Secondary Arc Current In Transmission Lines With Magnetic Valve Controllable Shunt Reactor

Long diatance and large capacity transmission is an inexorable trend for optimize resource allocation, developing ultra high voltage (UHV) AC transmission is an important issues of our nation's power grid field in the future. In order to supprss the overvoltage of power frequency and ensure the stability of reactive power compensation simultaneously, controllable shunt reactor is necessary to be installed on the high voltage transmission lines in our country. The main research task of this paper is applying magnetic valve controllable shunt reactor to supress secondary arc current. On the high voltage transmission line wih shunt compensation, the neutral small reactor can be adjusted to coordinate with shunt reactor to achieve the coordination control tactic between them, and then the final goal-the suppression of secondary arc current-could be reached.At first, this paper deduces and analyse three common ways of the magnitude of secondary arc current calclution. After comparison, the Twice-modal transformation way which is more practical than others is adopted to calculate the magnitude of secondary arc current about single circle line and double-circuit transmission lines through program designing in MATLAB software. Moreover this paper introduces the mathematical model and every parts of performance characteristics about magnetic valve controllable shunt reactor in detail. In terms of suppression effect of secondary arc current about using stable shunt reactors and neutral small reactor and coordination control tactic between shunt reactors and neutral small reactor, both theoretical analysis and simulation research are be made.Besides, this paper establish the equivalent circuit model of magnetic valve controllable shunt reactor in PSCAD. On that basis, the simulation circuit diagram of secondary arc current suppression with magnetic valve controllable shunt reactor is also built in PSCAD. And then, in the condition of low voltage experimental circumstance in aboratory wihic is made to simulate the real high voltage performance, the physical experiment about secondary arc current suppression with magnetic valve controllable shunt reactor is desived and achieved. Finally, the simulation result in PSCAD accords with wave form of oscillograph and power quality analyzer-topas 2000. In this way, the theoretical practicability and availability of this research task in this paper proves to be correct.