考虑预测不确定性的风-光-水多能互补系统调度风险和效益分析

风电、光伏与水电（简称风光水）互补发电系统是提高清洁能源整体利用效益的重要创新模式，随着风电、光伏发电渗透率的增加，如何解决大规模风光接入所带来的不确定性是多能互补系统研究的核心和难点。本文重点探讨日前风光出力预测的不确定性对于多能互补系统风险和效益的综合影响。首先，从可靠性、稳定性和经济性三个方面提出风光水多能互补系统调度运行风险和效益评价体系；建立多能互补系统短期优化调度模型，在日前风光出力预测结果基础上，编制系统日前发电计划；根据风光实际出力情况，滚动更新和模拟水电站实际调度过程。最后，对比分析各电站计划和实际调度运行情况，评价日前风光出力预测不确定性对于多能互补系统风险与效益的综合影响。本文以雅砻江流域锦屏一级多能互补系统为实例进行研究。相比风光水独立运行，风光水互补后系统的发电效益提高了37.13%，且系统出力过程更为稳定。互补系统在年尺度上具有良好的可靠性，但在水库低水位时期，系统失负荷天数明显增多，占全年失负荷天数的96%以上，系统可靠性降低；在汛期，互补后水库的下泄流量最大增加了47.06%，出现水量集中下泄的情况，这给电力部门、下游用水部门以及防护对象带来一定的防洪风险。

Risk and Benefit Analysis of Hydro-wind-solar Multi-energy System Considering the One-day Ahead Output Forecast Uncertainty

the hydro-wind-solar complementary system is an important innovation to improve the overall utilization benefits of renewable energy in China. With the higher penetration of renewable generation resources such as wind power and solar power, the uncertainty after integrating wind and solar is the core problem of multi-energy complementary system research. This paper discussed the risks and benefits of multi-energy system considering the uncertainty of one-day ahead wind and solar output forecasts. Specifically, the risk and benefit evaluation indices are proposed from three aspects of reliability, stability and economy. The short-term optimal operation model of multi-energy system is established, and the one-day ahead power generation plan is proposed using output predictions of diverse power plants. Then, the actual operation process of hydropower station is simulated and updated according to the actual output of wind and solar power plants following the one-day ahead power generation plan. Finally, the planed and actual operation process of each power station are compared, to evaluate the comprehensive impacts of output forecast uncertainty on the risks and benefits of the multi-energy system. Here, the multi-energy complementary system of Jinping I in Yalong River Basin which takes in 2.09 million kW solar power and 1.049 million kW wind power is taken as study case. The results show that the power generation benefits of the multi-energy system have increased by 37.13% compared with each power plant running independently, and also indicating more stable total output process. The multi-energy system shows good reliability at the annual scale. During the low water level period of the reservoir, the frequency of load loss condition increases significantly, accounting for more than 96% in the annual cycle, the system reliability is correspondingly undermined. During the flood season, the maximum release of the reservoir increased by 47.06% after multi-energy integration, which brings certain risks to the power generation and flood control of the basin.