规范大中型发电机主保护设计的方法

Normalizing the design method of main protection for large and medium sized generators

针对现有发电机主保护设计方法的不科学性 ,提出新的设计思路、步骤和方法 ,彻底改变了以往完全凭概念、经验和传统习惯的做法 ,逐步做到主设备继电保护设计工作的定量化 ,即以正确的发电机内部短路分析计算为基础 ,校核各种主保护方案的灵敏系数 ,由此择优确定发电机定子绕组中性点侧的分支引出方式 ,结合电机的实际情况和各种保护方案的优缺点 ,按照“优势互补、综合利用”的原则 。

Against the lack of scientific design method of main protection for generator at present, a new design view is presented in this paper. The design view entirely corrects the traditional configuration of main protection depended on the concept of protection, the experience of designer and the habitual configuration of other power stations. According to the view, the design of main protection scheme can be quantified. Firstly, the above method is based on the proper calculation of short circuit currents in stator windings. Secondly, the leading-out mode of branches at the neutral point of generator is determined by checking the sensitive coefficients of all kinds of protection scheme. Finally, considering the practical situation of generator and comparing the advantages and disadvantages of all kinds of protection, the final main protection configuration scheme is determined according to the design principle named advantage complementation and comprehensive utilization.