Risk Assessment And Control For Power Systems With Wind Farm Integration Based On Security Regions

With the rapid economic growth and people's pursuit of low-carbon green living,the use of new energy/clean energy for power generation,has become the focus of researchers all over the world.It is estimated that the total installed capacity of wind power in China will reach at least 150 million kilowatts by 2020.However,wind power output brings great challenges to the safe operation of power system due to its randomness,intermittent and other characteristics.Based on the security regions methodology,this paper studies the risk assessment and control method for power systems with wind farm integration,in order to provide a comprehensive understanding of system risk level and risk controlling measures.The main work of this paper mainly contains the following three points:(1)As to the overloading of transmission lines caused the N-1 fault,the coordinated control method of generation output/load based on thermal stability security region is proposed in the system without wind power integration.The method uses the security region to determine the minimum adjustment direction of the overloaded power flow to restore the normal operation,and obtain the final adjustment control strategy according to the principle of priority adjustment of power generation and ensuring that the load is operating steadily;(2)As to the problem of transient stability caused by wind power generation,the coordinated control method of synchronous generators,wind generators and system active loads based on dynamic security region is proposed in the system with wind power integration.Based on the work(1),this method further considers the principle of new energy priority generation and introduces the risk index to quantify the dispel-ability of power system with wind farms integration;(3)For high-risk periods of system with wind power integration,a way to calculate the up and down spinning reserve capacity is proposed based on dynamic security region with the constraints of EENS_t and EWWR_t.Test results on the IEEE standard example systems prove the effectiveness of this approach.The paper can provide a useful reference for power system operator decision-making.