异步电网直流配套电源开机优化研究

Analysis On The Optimum Operation Tactics of Plant Units Matching The HVDC of Asynchronous Grid

云南电网异步联网后网架强度有所下降,若云南直流送端电厂开机台数过少,直流解锁过程中有可能导致整流站交流母线电压越限,本文针对这一问题进行了仿真并得出了解决方案。文章首先分析了直流解锁过程中交流母线过电压的产生机理,并指出该过程中的暂态过电压是导致交流母线电压越限的主要因素。接着介绍了暂态过电压的计算方法以及其影响因素。根据暂态过电压与短路比的关系,采用南方电网2017年冬季小方式作为计算依据,并通过BPA进行仿真,得到了直流送端电厂的最小开机台数方案。然后与其他方式下的仿真结果做了对比,验证了仿真方法与结果的正确性。最后基于该结论,对2017年小方式实际开机方案进行了相关分析。

The voltage stabilization is protuberant during the deblock process of HVDC in the asynchronous interconnection of Yunnan power grid. This paper analysised the AC overvoltage reasons and found that transient overvoltage plays an important role. Then a method is introduced to calculate and analyze the transient overvoltage.According to the relationship of the transient overvoltage and short-circuit ratio, this method is verified by BPA.In the end, the optimum operation tactics of plant units is provided using the winter data of CSG in 2017.