基于火电机组分级深度调峰的电力系统经济调度及效益分析

Analysis of Deep Peak Regulation and Its Benefit of Thermal Units in Power System With Large Scale Wind Power Integrated

以风电规模化并网为背景,分析了我国现有火电机组的深度调峰能力,借鉴Manson-Coffin公式,给出了变负荷调峰下的机组损耗成本计算方法,建立了火电机组全过程调峰成本的分段函数;在全额接纳风电的基础上,以调度周期内火电机组总发电成本最小为目标,建立了基于分级深度调峰的电力系统经济调度模型。以某实际电网为研究对象,给出了不同调度策略下仿真结果,进而分析了基于等效替代的火电机组深度调峰效益。结果表明,对于算例系统,适当提高部分机组的调峰深度至额定容量的55%,可以提高整个系统的调峰效益;但是随着调峰深度的进一步增加,整个系统的火电机组深度调峰效益逐渐减小,在调峰深度大于额定容量的65%以后,深度调峰效益低于基本调峰。在规模化风电并网背景下,研究结果对制定相关火电机组参与深度调峰辅助服务的效益分析提供理论参考。

Deep peak-shaving capacity of thermal power units in power system with large scale wind power integrated needs further analysis. In this paper, a calculation method of unit loss cost was put forward and a piecewise function of peak-shaving cost for thermal power units was proposed. To minimize generation cost of thermal units, a calculating model of peak-shaving benefit based on step-by-step deep peak-shaving principle was established. In simulation of an actual power grid, generation cost of thermal units under different scheduling strategies was shown. Simulation results show that increasing peak-shaving depth of peak-shaving units appropriately, to 55% of rated capacity, can increase peak-shaving benefit, but further increase of peak-shaving depth will reduce benefit of whole system gradually. After increasing peak-shaving depth to 65% of rated capacity, the benefit is lower than that in basic peak-shaving stage. The results can provide theoretical reference for benefit analysis of deep peak-shaving auxiliary service of thermal power units.