抽水蓄能电站调压室设置判据及关键参数的影响机制研究

The surge chamber is one of the most effective engineering solutions to improve the unit's regulation performance and operating conditions and ensure the safe operation of the project. However, the research on surge chambers is mostly oriented to conventional hydropower station (HPS) currently. But for pumped storage power station (PPS) with more complex hydraulic transients, the research on setting criterion of surge chambers and influencing mechanism of key parameters still need to be improved.. Therefore, according to multiple PPSs and the combination of theoretical deduction, numerical simulation and prototype load rejection test, this project will be devoted to study the theoretical model and method for constructing the complete characteristic curves of pump-turbine, and to accurately predict the hydraulic transient in the PPS when the pump-turbine characteristics are unavailable; Based on the comprehensive consideration of water elasticity and pump-turbine characteristics, the setting criteria of headrace and tailrace surge chambers for PPSs will be proposed; Moreover, this project will identify the key influencing factors for setting a surge chamber, reveal the influencing mechanism of water hammer type, pump-turbine characteristics and grid parameters on setting a surge chamber through numerical simulation and prototype test. These research achievements can provide a scientific basis for guiding the design and safe operation of PPSs.

调压室是改善机组调节性能和运行条件，保障电站运行安全最有效的工程措施之一。然而，当前有关调压室方面的研究多集中于常规水电站，而对于水力瞬变过程更复杂恶劣的抽水蓄能电站的调压室设置判据及关键参数的影响机制等研究仍有待完善。. 本项目依托抽水蓄能电站实际工程，采用理论分析、数值模拟和原型试验相结合的手段，研究水泵-水轮机全特性曲线的理论构建模型和方法，实现在真机全特性曲线缺乏时较准确地预测模拟抽水蓄能电站中的水力瞬变过程；在综合考虑水流弹性和水泵-水轮机过流特性的基础上，理论推导适用于抽水蓄能电站的引、尾水调压室设置判据；识别抽水蓄能电站调压室设置的关键影响因素，通过数值模拟和原型试验，揭示包括水击类型、水泵-水轮机特性、电网参数等对调压室设置的影响机制。本项目研究成果可为指导抽水蓄能电站的设计及安全运行提供科学依据。

抽水蓄能电站是电力系统绿色低碳清洁灵活的调节电源，我国在当前及未来一段时期内将持续大力建设。然而，在抽水蓄能电站初步设计阶段，由于缺乏真机全特性曲线导致无法开展水力瞬变过程数值模拟，以及现有的常规水电站引、尾水调压室设计理论已经不适用于现阶段大容量抽水蓄能电站的设计和运行要求，给抽水蓄能电站的设计带来了诸多困难。为解决这些问题，本项目依托国内多座大型抽水蓄能电站工程，采用理论推导、数值模拟和原型甩负荷试验分析相结合的研究手段，深入开展可逆式水泵-水轮机全特性曲线的理论构建和抽水蓄能电站引、尾水调压室设置判据等研究。主要取得以下研究成果：（1）建立了描述可逆式水泵-水轮机全特性曲线的数学模型，提出了任意比转速水泵-水轮机全特性曲线的理论构建方法，实现了在真机全特性曲线缺乏时较准确地预测模拟抽水蓄能电站中的水力瞬变过程，提高了工程初步设计阶段水力瞬变过程的模拟精度；（2）综合考虑水泵-水轮机过流特性和输水系统水头损失，理论推导了抽水蓄能电站引、尾水调压室设置新判据，并基于国内外30座抽水蓄能电站的调研分析，绘制了抽水蓄能电站尾水调压室设置判别经验曲线，提出的新判据和判别经验曲线可以作为抽水蓄能电站引、尾水调压室设置与否的初步判别标准；（3）在利用原型甩负荷试验实测数据验证了水力瞬变过程数值模拟精度的基础上，通过数值模拟，识别了水力瞬变过程的关键影响因素，揭示了各影响因素对调节保证参数的影响机制。研究成果对于指导我国抽水蓄能电站工程设计、确保工程的运行安全具有重要参考价值。