Verification by current control of multi-phase transformer-linked type boost chopper circuit using current sensorless method

A Boost chopper circuit for Electric Vehicle and Hybrid Electric Vehicle are required miniaturization and high power density. Multi-phase transformer-linked type boost chopper circuit is an effective method for miniaturization of the circuit. In this circuit, the miniaturization of a smoothing capacitor and each phase inductor are half as compared with single-phase boost chopper circuit. However, since each phase is asymmetry by parasitic elements, its circuit arise imbalance of current of each phase. Therefore, multi-phase boost converter is necessary for current control such as balance of current of each phase. However, this circuit increases number of phase at the same time as increase number of current sensors too. Increase number of current sensor is become a problem such as increase in cost, grow in size of the circuit, increase of error of the gain of the current sensors of each phase. In this paper, comparison and verification of current control of both are using current sensorless method in multiphase transformer-linked type boost chopper circuit. In the result, average current mode control is confirmed by simulation and experimental result that the response of the control is better than current balancing control.