Generalized Small-Signal Averaged Switch Model Analysis of a WBG-based Interleaved DC/DC Buck Converter for Electric Vehicle Drivetrains

Abstract

To achieve a high-performance index and accurate controllability of power electronics converters (PEC), generalized small-signal analysis of the closed-loop power electronics converters is a key aspect. This article presents a detailed generalized small-signal averaged switch model (GSSASM) of a Wide Bandgap (WBG)-based Interleaved DC/DC Buck converter (IBC) for electric vehicle (EV) drivetrains to better understand the circuit characteristics, performance, stability and control systems. The derived GSSASM considers the power electronics device (e.g., switch & diode) and passive components (inductor, capacitor and internal resistance of input source), which can result in an accurate mathematical model representing the real-time (RT) system. The proposed model can be utilized for any number of phases in the IBC systems. Furthermore, a field-programmable gate array-based (FPGA) programming board of dSPACE MicroLabBox, is used to validate the proper control compensators towards high dynamic performance in the Real-Time Workshop (RTW)-system. Finally, the performance of the proposed mathematical model is verified with a 30-kW SiC-based IBC prototype in both transient and steady-state conditions, respectively.