不同灭磁配置与灭磁时间特性分析

Analysis method of de-excitation characteristics

随着大型同步发电机灭磁技术的发展,形成了多种不同的灭磁方式和灭磁配置,实践中如何测试及评价灭磁的性能效果是亟待解决的一大课题。以几种典型灭磁方式为例,结合工程测试数据,运用数据分析处理方法,将孤立有限的数据整合推算出完整的灭磁特性。对于灭磁时间特性,引入"等效转子时间常数比较法",实现了对于不同机组、不同配置参数的灭磁特性综合比较,并重新提出建立以空载理想灭磁条件为参照的灭磁性能技术评价体系,为进一步规范和健全统一的灭磁性能标准打下基础。以葛洲坝和三峡的大型、超大型水电机组为对象,探索一种客观评价灭磁性能的方法,并对取得的结果进行总结。

Some kinds of different de-excitation methods and de-excitation dispositions are formed along with the development of modem excitation systems of large-scale generators. But it is a big problem to test and evaluate the performance of de-excitation. Taken the typical de-excitation methods as the examples, combined with the data tested in projects and using the method of data analysis and processing, the whole de-excitation characteristics were obtained. The comparative method of equivalent rotor time constant was introduced for de-excitation time characteristics, which realized the comprehensive comparison of de-excitation characteristics for different generator units and different disposition parameters. It was re-presented to establish an evaluation system for de-excitation performance. The paper discussed the objective evaluating method of de-excitation characteristics by taking large-scale hydro-electric equipments in Gezhouba and Three Gorges as the target, and the results for which were summarized.