抽水蓄能机组孤网运行稳定特性分析

由于抽水蓄能机组抽水调相转为抽水工况,后加负荷速度不可控,启停过程中负荷跃变剧烈,孤网期间容易影响电网频率稳定.为着力解决长期以来困扰海南电网"大机小网"下的频率稳定问题以及排查可能存在的安全稳定威胁,文章依据抽水蓄能机组同步机、水轮机及其调速器的数学模型,构建了水轮机调速器环节与同步机转子运动环节的动态反馈线性化模型.通过BPA仿真计算,研究了水轮机调速器动态对抽水蓄能机组的频率稳定性的影响.通过计算海南电网频率稳定性与机组功角稳定性,确定了抽水蓄能机组单机最大容量.该研究为未来海南电网稳定运行、抽水蓄能机组孤网运行提供了可靠的借鉴.

Analysis of stability characteristics of isolated network of the pumped storage unit

Since the loading speed of the pumped storage unit is not controllable after the pumping phase is transferred to the pumping condition, the load jumps violently during the start-up and shutdown process, which may easily affect the stability of the power grid frequency during the isolated period. In order to solve the problem has long plagued frequency stability of Hainan power grid under the "big machine small net" and eliminate the possible threats to safety and stability, according to the mathematical models of the synchronous machine, the water turbine and its governor of the pumped storage unit, this paper establishes the dynamic feedback linearization model of the turbine governor link and the rotor motion link of the synchronous machine. The influence of turbine governor dynamics on the frequency stability of pumped storage units was studied by BPA simulation. By calculating the frequency stability and power Angle stability of Hainan power grid, the maximum capacity of pumped storage unit is determined. This study provides a reliable reference for the future stable operation of Hainan power grid and isolated operation of pumped storage units.