All-SiC ANPC Submodule for an Advanced 1.5 kV EV Charging System under Various Modulation Methods

Abstract

This work is focused on the design and experimental validation of the all-SiC active neutral-point clamped (ANPC) submodule for an advanced electric vehicle (EV) charging station. The topology of the station is based on a three-wire bipolar DC bus (±750 V) connecting an ac grid converter, isolated DC-DC converters, and a non-isolated DC-DC converter with a battery energy storage. Thus, in all types of power converters, the same three-level submodule may be applied. In this paper, a submodule rated at 1/3 of the nominal power of the grid converter (20 kVA) is discussed. In particular, four different modulation strategies for the 1.5 kV ANPC submodule, exclusively employing fast silicon carbide (SiC) MOSFETs, are considered, and their impact on the submodule performance is analyzed. Moreover, the simulation study is included. Finally, the laboratory prototype is described and experimentally verified at a switching frequency of 64 kHz. It is shown that the system can operate with all of the modulations, while techniques PWM2 and PWM3 emerge as the most efficient, and alternating between them, depending on the load, should be considered to maximize the efficiency. Furthermore, the results showcase that the impact of the different PWM techniques on switching oscillations, including overvoltages, can be nearly fully omitted for a parasitic inductance optimized circuit, and the choice of modulation should be based on power loss and/or other factors.

Analysis of SiC and SiC-Cascode MOSFET in the design of power electronics converters for more electric aircrafts

“…Several previous studies reported in [4], [5], [9]- [15] prove the effective gain in performance when WBG semiconductor devices are applied in power electronics converters, encouraging their increasing application in the industrial and academic environment. Additionally, recent studies concerning the deployment of SiC [16]- [21] and GaN [22], [23] technologies in several applications, the latter being used in high-power devices, as reported in [24].…”