Study on voltage control in distribution network with renewable energy integration

Abstract

Currently the issue of renewable energy related encourage policies, high penetration of renewable energy connect to the distribution network would lead to increased voltage levels, short circuit current increases, power supply reliability and power quality deterioration and other problems are particularly prominent. In the traditional distribution network, the uncertain factors that affect the voltage optimization result are the fluctuation of the load. The renewable energy integration represented by wind power and PV power not only changes the characteristics of the traditional distribution network power flow, but also because of its power electronic converter connection, making the distribution network voltage characteristics, whether steady or transient have brought significant changes, and then the distribution network voltage control has brought great challenges. To maintain the distribution network voltage level, how to set a reasonable control strategy for different renewable energy network connection situation makes the voltage in the distribution network be reasonably controlled and optimized to become an urgent problem to be solved. In order to achieve flexible control system supply voltage, improve the level of reactive power operation, and meet the demand of power users under the conditions of the initiative to network and renewable energy power generation operation optimization and control. In this paper, the voltage control problem of distribution network under the condition of large-scale renewable energy integration is studied. Firstly, the voltage characteristics of the distribution network under the uncertainty of renewable energy output are analyzed, and the voltage sensitivity analysis model of renewable energy connect network is established. On this basis, put forward renewable energy voltage control strategy, and finally a regional distribution network system as a case to verify the proposed method and strategy of correctness and effectiveness.