Precise Disturbance Rejection for Dynamic Wireless Charging System of Electric Vehicle Using Internal Model-Based Regulator With Disturbance Observer

Dynamic wireless charging (DWC) of electric vehicles (EVs) is a promising technology that can promote the widespread acceptance of EVs. However, the power fluctuation issue caused by the EV motion is quite challenging, which can lead to the deterioration of control performance and even system instability. This article proposes a compound control strategy to compensate for the disturbances arising from the mutual inductance fluctuation caused by the EV motion in DWC system. The influences of disturbances are first investigated and the structural properties of these disturbances are also given. Disturbance caused by the longitudinal misalignment of the EV motion can be described by an exosystem and be compensated by an internal model-based regulator. And the other unmodeled disturbance caused by the lateral misalignment of the EV motion can be compensated by adding a disturbance observer. This observer works in parallel with the internal model-based regulator through a feedforward compensation channel. Finally, the effectiveness of the proposed control strategy is evaluated experimentally. A DWC prototype is constructed and the experimental results demonstrate that the output voltage fluctuation rate is within 1% no matter whether the lateral misalignment is taken into account and the output power fluctuation rate during EV motion is only 0.2%, which verifies the stronger disturbance rejection capability and better steady-state accuracy of the proposed control method compared to other traditional methods.