1. Authors: Do-Hyeon Kim, Han-Vit Kim, Joon-Seok Kim, and June-Seok Lee

2. Title: Voltage Feedforward Control and Time delay Compensation of WFSM for eliminating Current Transient

3. Published in: 2024  IEEE Energy Conversion Congress and Exposition (ECCE)

: This paper proposes a voltage feedforward control to consider the cross-coupling of the wound field synchronous motor (WFSM) that generates a field flux using a field current. Since the d-axis stator winding and the field winding of WFSM are mutually coupled, the d-axis flux linkage affects the field flux. Furthermore, since the field winding has more turns than the stator winding, a change in the d-axis current induces an electromotive force (EMF) in the field winding. The EMF produces a current transient of the field current and distorts the d-axis flux. This phenomenon indicates the presence of additional crosscoupling components in the WFSM. The additional cross-coupling components can generate torque ripple and degrade the performance of the current controller. This paper analyzes the cross-coupling between the d-axis and field winding of the WFSM and presents a feedforward voltage to compensate for the crosscoupling component. In addition, using the digital controller leads to the problem of the feedforward voltage not being compensated when the current changes. To solve this problem, the predicted daxis current based on the modeling of the WFSM is proposed to calculate the feedforward voltage. The validity of the proposed method is verified by simulation results.