Research and software development on auxiliary checking method of harmonic tolerance for substation main equipment

The working state of the main equipment directly determines whether the substation can work normally or not, even when the main equipment works in normal state, there are always accompanied by complex harmonics, therefore. In this paper, the harmonic tolerance capacity checking method for power transformer, on-load tap switch, and filter are proposed, the harmonics tolerance capacity checking can provide accurate evaluation to judge whether the main equipment is working in proper state, which can further ensure the safe operation of substation. Firstly, the basic theory for harmonic tolerance capacity checking is studied. Secondly, the auxiliary tools for harmonics tolerance capacity checking are developed. Finally, the test examples are conducted to verify the effectiveness of the developed auxiliary tools. The checking results shows that the proposed checking method has high accuracy and the developed checking software has well practicability.