Characteristics in transformer operation mode of linear motor-transformer apparatus

The characteristics of linear transformer are studied analytically, which is composed in one of modes of linear motor-transformer apparatus proposed for future wireless LRV (light rail vehicle). The secondary (onboard) power factor can adjusted at any value by onboard converter. The equivalent circuit is used to study the transferred power control. The parameters are determined by three-dimensional FEM (finite element method) 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 to 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 for the control of secondary power factor of 0.4 under the condition without input capacitor.