Multiple Coils IPT System Implementing CV Output Characteristics with Improved Misalignment Tolerance

With the rapid development of inductive power transfer (IPT) systems, misalignment between IPT pads has become a common issue especially in practical applications of IPT systems. Therefore, it is important to improve the misalignment tolerance of the IPT pads. In this paper, a multiple coils IPT system is proposed to implementing the constant voltage (CV) output characteristics with high misalignment tolerance. By applying two DD pads connected in series in the transmitter side and a bipolar pad including two coils respectively compensated in the receiver sides. The influence of the mutual inductance variations when misalignment happens can be reduced. Therefore, a relatively high misalignment tolerance in Y direction can be achieved and the misalignment tolerance in X direction is remarkable improved. The basic analysis of the proposed IPT system is given. And the design process is elaborated. To verify the performance of the proposed IPT system, a 1kW experimental prototype is designed and built. The experimental results show that the fluctuations of the output voltage are less than 5% and 30% with 250mm misalignment in Y direction and 225mm misalignment in X direction, respectively.