Output Current Identification Based on the Kalman Filtering Algorithm for Magnetic-Coupling Excitation System

Magnetic-coupling excitation system is one of the research highlights in the field of brushless Electrically Excited Synchronous Motor (EESM), which contains the primary energy emission device and a secondary receiving device that rotates synchronously with the motor rotor. Primary-side control estimation is widely applied in Wireless Power Transmission (WPT) system to detect the output current of the secondary device to reduce the weight of rotor and achieve the merit of communication-free. A magnetizing current estimation method based on the Kalman filter algorithm is proposed for a novel system combined with EESM and WPT. The proposed method adopts the Kalman filter algorithm to the magnetizing current estimation model, which eliminates the higher-order harmonics in the sampling of inverter current and transmitting coil current. In addition, the output current control is achieved by applying the PI controller. The simulation result of proposed system in Matlab/Simulink proves the enhancement of proposed method on the accuracy, the transient response speed and the tracking performance of magnetizing current estimation.