间歇式电源并网系统的中长期特性仿真研究

Simulation of Medium-and Long-Term Characteristics of Power Grid Integrated With Intermittent Energy Sources

间歇式电源的大规模发展及并网运行,在带来巨大经济效益的同时,也给电网中长期过程的频率稳定和有功平衡带来了巨大的影响。在间歇式电源机电暂态模型的基础上,对风电、光伏中长期自动发电控制(automatic generation control,AGC)子站进行建模,该模型可以接受调控中心AGC总站的调度命令,对间歇式电源进行功率调节。然后,利用甘肃电网的某典型日负荷、风速及光照曲线,深入分析了间歇式电源的波动特性及风光互补特性,验证了上述模型具有模拟中长期频率波动的能力。在此基础上,以平抑间歇式电源带来的联络线功率波动为目标,对机组出力计划、二次调频系统等控制策略的效果进行了分析。最后通过仿真计算论证了机组出力计划和AGC系统具有平抑间歇式电源功率波动性的作用。

The large-scale development of intermittent energy sources and their grid-connection bring huge economic benefit, in the meanwhile it greatly impacts on frequency stability and active power balance in the medium- and long-term process of power grid. Based on electromechanical transient model of intermittent energy sources, the modeling of medium- and long-term automatic generation control （AGC） substation for wind farm and photovoltaic （PV） power station is carded out. The established model can receive the scheduling command from AGC master station in dispatching ar control center to adjust the power output of intermittent energy sources. Based on the data of Gansu power grid and typical daily load curve, wind speed curve and illumination curve, the fluctuation characteristic of intermittent energy sources and the wind-solar complementary characteristic are analyzed in depth, thus the correctness of the above-mentioned model that it possesses the capability to simulate the medium- and long-term frequency fluctuation is validated. On this basis, the stabilization of the power fluctuation in the tie line brought by intermittent energy sources is taken as the objective, the effects of control strategies such as the unit commitment and AGC are analyzed. Finally, it is validated by simulation results that the unit commitment and AGC possess the capability of stabilizing the power fluctuation due to intermittent energy sources.