Design and Implementation of FPGA-based Digital Controllers for SiC Multiport Converter in Electric Vehicle Drivetrains

This article presents the practical design and performance comparison of Field Programmable Gate Array-based digital controllers for SiC-based Multiport Converters (MPCs) in electric vehicle drivetrains. Each input port of the MPC consists of a non-isolated three-phase Interleaved Bidirectional Converter. Two different controllers are designed and compared in this work: a type-II controller designed based on the 'k-factor' approach and a conventional Proportional-Integral (PI) controller. In particular, the controller design in boost mode is challenging due to the non-minimum phase issue and the presence of Right-Half-Plane Zero (RHPZ). Based on the digital redesign approach, the controllers transfer functions are first derived in s-domain and then transformed to z-domain for direct implementation in the FPGA board of dSPACE MicroLabBox with the graphical programming tool Xilinx System Generator plugged-in the Simulink environment. Finally, experimental results show the proper dynamic performances of both controllers.