湖南电力 ›› 2026, Vol. 46 ›› Issue (5): 16-23.doi: 10.3969/j.issn.1008-0198.2026.05.003

• 源网协调与能源转换利用 • 上一篇    下一篇

考虑调速器与励磁调节特性的小水电孤岛电网电压与频率特性分析

谭力铭1, 欧阳帆1, 李振文2, 刘永刚2, 肖繁3, 欧阳宗帅1   

  1. 1.国网湖南省电力有限公司电力科学研究院,湖南 长沙 410208;
    2.国网湖南省电力有限公司,湖南 长沙 410004;
    3.武汉理工大学,湖北 武汉 430070
  • 收稿日期:2026-06-23 修回日期:2026-07-19 发布日期:2026-11-06
  • 通信作者: 谭力铭(1998),硕士研究生,助理工程师,研究方向为电力系统继电保护。
  • 基金资助:
    国网湖南省电力有限公司科技项目(重大专项)(5216A525000C)

Analysis of Voltage and Frequency Characteristics of Small Hydropower Islanded Grid Considering Governor and Excitation Regulation Characteristics

TAN Liming1, OUYANG Fan1, LI Zhenwen2, LIU Yonggang2, XIAO Fan3, OUYANG Zongshuai1   

  1. 1. State Grid Hunan Electrical Power Company Limited Research Institute, Changsha 410208, China;
    2. State Grid Hunan Electrical Power Company Limited, Changsha 410004, China;
    3. Wuhan University of Technology, Wuhan 430070, China
  • Received:2026-06-23 Revised:2026-07-19 Published:2026-11-06

摘要: 现有研究将小水电孤岛电网电压与频率视为解耦的独立变量分析,往往忽略恒阻抗负荷和同步电抗频率依赖性所导致的电压-频率耦合效应。针对此问题,建立考虑调速器下垂特性和励磁系统饱和约束的电压-频率耦合稳态解析模型,推导孤岛电网电压与频率的联立求解方程组,揭示励磁饱和对稳态运行点的影响机理。搭建含小水电机组的10 kV不接地配电网仿真模型,在50%~150%负荷水平下验证耦合模型的正确性。仿真结果表明:孤岛形成后励磁系统快速响应并可能饱和于顶值,电压-频率耦合效应完全显现,恒阻抗负荷的电压依赖特性无法弥补重载工况下超出机组容量的功率缺额。

关键词: 小水电, 孤岛电网, 电压-频率耦合, 调速器, 励磁调节, 稳态解析模型

Abstract: Existing studies mostly treat voltage and frequency as decoupled independent variables, neglecting the voltage-frequency coupling effect caused by constant-impedance loads and frequency-dependent synchronous reactance. This paper establishes a coupled voltage-frequency steady-state analytical model considering governor droop characteristics and excitation saturation constraints, derives simultaneous voltage-frequency equations for the islanded grid, and reveals the impact mechanism of excitation saturation on steady-state operating points. A simulation model of a 10 kV neutral ungrounded distribution network incorporating small hydroelectric generating units is established, and the correctness of the coupled model has been verified under load levels ranging from 50% to 150%. Simulation results show that the excitation system rapidly saturates at its ceiling after islanding, fully exposing the voltage-frequency coupling effect. The voltage-dependent characteristic of constant-impedance loads cannot compensate for the power deficit exceeding unit capacity under heavy-load operating conditions.

Key words: small hydropower, islanded grid, voltage-frequency coupling, governor, excitation regulation, steady-state analytical model

中图分类号: