变速抽水蓄能机组功率优先控制模式的运行稳定域分析

Analysis of Frequency Stability Regions under Power Fast Mode in Variable Speed Pumped Storage Plants

变速机组相较于传统定速机组在运行和调节中具有快速、高效、灵活和可靠等优点。然而变速抽水蓄能电站刚刚起步,其在有功功率调节过程中的运行稳定性需要进一步研究。本文中基于MATLAB和Simulink作为主要工具研究变速抽水蓄能电站在有功功率调节中的动态稳定性。首先,建立了一个变速抽水蓄能电站的水-机-电耦合的数学模型。然后,建立13阶状态矩阵用于理论研究系统的动态稳定性,并进行时域模拟进一步验证和分析,验证了理论矩阵和数学模型的有效性和合理性。结果表明,变速抽水蓄能机组在并网条件下的有功功率调节的过程中,可能面临失去稳定性的风险,这是定速机组不会出现的新问题。因此,在变速抽水蓄能电站的设计和运行过程中,需要重点关注系统特性参数与控制参数的匹配问题。研究结果可为提高变速抽水蓄能电站调节稳定性提供技术参考。

Variable speed units(VSUs)demonstrate advantages compared to conventional fixed speed units(FSUs),such as rapidity,high efficiency,flexibility,and reliability in operation and regulation.However,variable speed pumped storage plants(VSPSPs)are still in the early stages of development,and their operational stability during active power regulation requires further investigation.In this paper,the goal is to study the dynamic stability of VSPSPs in active power regulation,based on MATLAB and Simulink as the main tools.First,a numerical model integrating hydraulic-mechanical-electrical subsystems of VSPSPs with doubly fed induction machines is adopted by using MATLAB/Simulink,and a thirteenth-order state matrix is established for theoretical eigenanalysis as the core approach.Then,the time-domain simulations are conducted for further validation and illustration,and the validity and rationality of the theoretical matrix and model are verified.The results show that,even under the grid-connected condition,the VSUs could also lose stability during the active power regulation,which is a new issue that will not arise in FSUs.Therefore,it is necessary to focus on the matching problem between system characteristic parameters and control parameters in the design and operation process of VSPSPs.These results could provide suggestions and technical support for increasing the stability of the operation and regulation of VSPSPs.