The characteristics of linear transformer are studied analytically. The transformer is composed in one of modes of linear motor-transformer apparatus proposed for future wireless light rail vehicle (LRV). The secondary (onboard) power factor can be adjusted at any value by an onboard converter. The equivalent circuit is used to study the transferred power control. The parameters are determined by three-dimensional finite element method (FEM) analysis for one pole-pair model. Under the rated primary (input) and secondary voltage and current, which are specified for linear motor operation, the characteristics of the secondary power factor are cleared. It is also shown that the input capacitor can improve the primary power factor and decrease the input power capacity, but does not change the efficiency. This linear transformer has the efficiency of 91% and the input power factor of 0.87 when the apparatus without input capacitor is controlled at the secondary power factor of 0.4.
Linear Motor, LIM, Linear Transformer, Non-Contact Power Collection, Wireless LRV, FEM, Finite Element Method, Power Factor, Equivalent Circuit
Fujii, N. , Kanamitsu, S. and Mizuma, T. (2011) Transformer Characteristics of Linear Motor-Transformer Apparatus. Journal of Transportation Technologies, 1, 94-101. doi: 10.4236/jtts.2011.14012.
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