Risk Assessment And Control Of Power System With Large-Scale Wind Power Connected

Along with the economic development, the growing problem of resources environmental stimulates the integration of wind power in power system. Currently, the mainly wind turbines integrated are variable speed wind turbines (including Doubly Fed Induction Generator and Permanent Magnet Synchronous Generator wind turbines). Seven wind power base would be build due to 2020, which include Hami, Jiuquan, Zhangbei, Jilin, Jiangsu, Mengdong, Mengxi. The active output power of variable speed wind turbines is decoupled with power system frequency, and the active output of wind turbines can't change to decrease the system frequency deviation under power system fault condition. Unlike conventional generators, the maximum active output power of wind turbines depends on wind speed, and the volatility of net load is strengthened, which aggravates the operating stress and increases the operating cost of AGC units. Particularly in the case of high wind speed, the wind turbines may be cut out from power grid if the wind speed is higher than Cut-off wind speed, which will cause severe active power disturbance on power system. Especially the power grid with large-scale centralized wind power connected as in china, wind power ramp event may bring great operating risk to power system.Aims at the active power balance problems brought by wind power integration, several problems are studied from risk assessment and predictive control. Including risk assessment of power system with wind power ramp event based on prospect theory, reserve demand analysis and preventive controls to deal with wind power ramp event. A risk assessment model of power system with wind power ramp event based on sequence operation theory is proposed with large wind power connected. The characteristic and development process of wind power output charcteristic is analyzed, and two risk indicator are proposed include Expected Load Lossed Probability and Expected Energy Not Supplied. A reserve demand analysis and preventive control model to deal with wind power random fluctuation is proposed to solve the above problems. The schedule strategy is adjusted along with the implementation of dispatch schedule, the dispatching schedule is adjusted according to the newest predication information with it, and the adjustment includes the curtailed amoumt of wind power, the output power and reserve capacity of conventional generators. The conclusion is demonstrated with the simulation on IEEE RTS 24 system.