Power System Phase Sequence
In the power system,most of the generators produce electric power with three phases,most of the power lines have three phases,and most of the large capacity motors convert power energy to mechanical energy with three phases.The relationship of three phases is aptotic and is called phase sequence.There are three phase sequences:positive phase sequence,negative phase sequence,zero phase sequence.Traditionally,the phase sequence is figured by geometry method. I have worked in electric power vocation for more than 50 years.In 1950s,I worked at Hengyang,Hunan province.There were many accidents caused by phase sequence disorder in southern Hunan power system.The phase sequence disorder in southern Hunan power system was corrected after many years of hard work.I found an algebra method to figure phase sequence,it was very useful and gave me much help.So,I write this article 《power system phase sequence》.