Analysis and design of LCC resonant inverter for the tranportation systems applications

The analysis and design of an LCC-type power resonant inverter for transportation application in a train system is presented in this paper. The inverter powers the linear induction motor (LIM) used in urban transit applications. It has low components stresses compared with the conventional series and series-parallel resonant topologies. The voltage regulation is achieved by using a self-oscillating controller that results in high power efficiency for wide range of current motor operation. Moreover, by using an optimized transformer leakage inductance value, Zero-Current Zero-Voltage (ZCZVS) operation is achieved for the primary-side IGBTs, which allows for high switching frequency operation with lower power losses, resulting in increased power density. The ZCZVS operation is achieved without using an auxiliary circuit by utilizing the switches capacitances and the transformer leakage inductance. The paper presents the theoretical analysis, which is used in the design of the power inverter. Experimental results based on 750 Vdc/700 Vac 400 kW design are presented to verify and evaluate the LCC-type resonant inverter.