奇数多分支大型水轮发电机主保护设计的特点

为保证大型发电机组的安全运行,在工程实践经验积累的基础上,有必要对发电机主保护配置方案的定量化设计过程进行归纳总结,以使其更好地服务于工程实践。该文以百色(135MW)、乐滩(150MW)、凤滩(200MW)、瓦屋山(130MW)、彭水(350MW)、拉西瓦(700MW)电站的6台水轮发电机的主保护设计为例,说明奇数多分支水轮发电机主保护的设计过程可归纳为一个每相3分支的水轮发电机主保护配置方案的设计,应立足于如何使用不完全裂相横差保护,即根据发电机实际可能发生的故障特点,舍弃每相某一分支的同时实现对剩余偶数分支的合理分组(相邻或相隔方式);相关设计规则的总结为奇数多分支大型水轮发电机主保护配置方案的定量化设计明确了方向,同时也显著地减少了设计计算的工作量。应用该方法可进一步简化发电机主保护配置方案的定量化设计过程。

Design Characteristic of Main Protection Configuration Scheme for Large-sized Hydro-Generators With Odd Branches

Based on the engineering experiences, it is necessary to summarize quantitative design process of main protection configuration scheme and supply high-grade assurance for the safe operation of large-sized hydro-generators, which is beneficial to spread the quantitative design method in the engineering field. With the main protection designs of six hydro-generators in Baise, Letan, Fengtan, Wawushan, Pengshui and Laxiwa power stations as example, the design process of hydro-generators with odd branches can be reduced to the main protection design of hydro-generators with three branches per phase and the usage of incomplete split-phase transverse differential protection is becoming significant. According to the possible fault features of different hydro-generators, one branch per phase is abandoned and other even branches per phase are reasonably grouped at the same time, such as adjacent or alternating modes. The summary of corresponding design rules directs the quantitative design for main protection configuration scheme, which greatly reduces the computation workload and ensures the accomplishment of design work. The quantitative design process of main protection configuration scheme for hydro-generators can be further simplified using the presented method.