Research On Relay Protection Of Distribution Network With Wind Power

The wind power technology has been rapid development with the emergence ofthe problem of environmental pollution and energy crisis, and with the constantexpansion of wind power, the impact of wind power on the grid become more andmore apparent. Due to the wind energy is random and intermittent, it makes protectiondifficult with wind power access system.Based on the mathematical model of wind turbine, the simulation model of theasynchronous and double-fed wind turbine is built on the platform of PSCAD/EMTDC,and the mode is verified by the actual running characteristics of wind turbines.Short-circuit current characteristics of the ordinary induction wind turbine and thedouble-fed wind generator is analyzed, then the failure characteristics of the distributionnetwork containing wind farm is simulated, and the main factors on fault current andprotection with wind power system is analyzed。The relational expression of faultcurrent in the distribution network containing wind farm is established, and the featuresof the fault current are analyzed. Asimulation model of distribution network containingwind farm is built, and the impacts of the capacity of wind farm, its network-connectedposition and fault point on fault current in distribution network and protective relayingare researched by the built model. the paper analyzed the protection schemes of thedistribution network containing wind farm and proposed improvement program. Thedistribution network containing wind farm is sub-regional based on the wind farmnetwork-connected position. The upstream area of the wind farm configured directionlongitudinal protection, and directional element is installed at the current protection.The downstream area of the wind farm configured adaptive current protection, Throughsimulates and analysis based on MATLAB，the results show that the adaptive currentprotection scheme is good to overcome the problem of downstream protection loss ofselectivity.