A Practical Implementation of a SiC Based 5kW, 3-level MPPT Boost with 90W/inch(exp3) Power Density and 99.2% Peak Efficiency

Abstract:
The concept of multi-level converters has been recognized for many years. However, recent innovations in semiconductor power devices, enhanced computational capabilities of microcontrollers, and advancements in magnetic materials have significantly enabled the pursuit of higher efficiency and the implementation of complex control strategies. This paper highlights a three-level MPPT boost converter utilizing a flying capacitor topology, aimed at enhancing renewable energy storage applications. The paper primarily focuses on the hardware design using SiC MOSFETs and the implementation of a digital control loop using a single 32-bit ARM microcontroller. The three-level converter realized is rated at 5kW and operates with an input voltage ranging from 400 to 750V DC, connected to an 800V DC output bus to supply power to a battery bank or an inverter. The developed system exhibits a power density exceeding 90W/inch³ and achieves a peak power conversion efficiency of 99.2%.