相转换 meaning in English

phase conversion
phase transition

The main achievements of the thesis are as follows : ( 1 ) kinds of techniques to detect magnetizing inrush of traction transformers are thoroughly investigated in this paper , and their limitation are indicated and corresponding improvement techniques are proposed . ( 2 ) in this paper , flux linkage equilibriun equations are used to build " ash - box " models of some traction transformers based on system identification , such as two - winding single - phase traction transformer , impedance - matching equilibriun traction transformer and scott traction transformer
论文的主要内容有：（ 1 ）详尽分析了现有的针对牵引变压器励磁涌流算法的保护算法，提出了每种算法的局限性及其改进方法；（ 2 ）提出适用于铁道电气化系统中各种牵引变压器对应的三?二相转换规则，利用该规则可将对应量的转换置于保护软件中，从而可大大减轻在牵引变压器两端外部复杂的接线。