地区电网解列后安全稳定控制研究-电气工程专业论文.docxVIP

摘要 摘 要 -I- -I- 摘 要 近年来我国一些地方冰雪、风暴、泥石流等自然灾害时有发生，地区电网与主 网解列的风险凸显，保证地区电网解列后的频率稳定和安全日益受到关注。本文根 据孤网高频事故总结了孤网高频特征，对地区电网解列后安全稳定控制措施的研究 动态进行了综述，随后从三个方面对地区电网解列时的频率稳定控制技术进行了较 为深入的研究。 (1)针对小水电汇集型送端地区电网解列故障，提出了高频控制措施的配置原 则，对云南某水电外送型地区电网配置了连锁切机和高频切机方案，具有层次清晰、 易于实施的特点。设置地区电网的高频切机方案时一方面考虑了与云南 500kV 主网 高频切机方案相协调，另一方面可应对地区外送通道解列故障和地区内部不同片区 单独解列故障不同场景下的高频问题。通过典型运行方式下解列故障的仿真，对配 置方案的有效性进行了验证。 (2)针对大水电、小电网型送端地区电网，进行了解列故障时的水电机组孤网暂 态频率特性和控制策略研究。分析了水电机组的过速保护和过电压保护的配置情 况，以大型水电机组外送功率典型系统为例，研究了解列故障时大型水电机组的调 控特性，提出了一种应对解列故障的水电机组调频控制改进方案，通过测量解列前 地区电网外送功率值，对原有调速控制系统进行改进，包括更新控制目标值和加入 呈衰减特性的前馈信号，实现对频率飞升的控制和超调现象的抑制，仿真结果验证 了改进方案的有效性，为提高地区电网抵御解列故障的能力提供参考。 (3) 建立了完整的包括协调控制系统(CCS)和锅炉的火电厂调速系统模型，以此 为基础，研究了火电机组调速控制特性。以大型火电机组外送仿真系统为例，研究 了送端电网解列故障下火电机组调速系统的重要参数对电网频率动态过程的影响。 以河南某受端地区电网为研究对象，研究了地区电网解列后的低频特性，提出了增 强机组调频能力的建议。 关键词：孤网；解列；水轮发电机组；频率控制；火电机组；协调控制 Ab Abstract -II- -II- Abstract In recent years, natural disasters such as snow, ice storms and mudslides have occurred in some places of China, highlighting the risk of splitting the regional power grid and the main grid, so there is growing concern about ensuring stable and secure frequency of the regional power grid after its splitting. According to high-frequency incidents caused by isolated grids recently, the paper sums up the high frequency characteristics, reviews the domestic and foreign research tendency on security and stability control measures after the splitting of regional power grids and then studies about the frequency stability control after splitting failure of regional power grids from three aspects. Now the paper summarizes its work as follows: For splitting failures of power grids occurred in areas which are provided with power by collection of small hydropower, this paper presents the configuration principles for high-frequency control measures of grids. Chain generator tripping and high-frequency generator tripping schemes are provided for the power grid of delivery region in a hydropower station of Yunnan. It is characterized by clear