Medium-Voltage Seven-Level Multiplexed Converter for AC Applications

Abstract

After several decades of technological evolution, power electronics applications have become extremely important for electric/hybrid propulsion systems, smart grids, renewable energy systems, energy saving, and bulk energy storage, besides the typical applications in industrial automation and high-efficiency energy systems. In all these applications, a power conversion system with high efficiency and power density is required without sacrificing the system's power quality. The paper describes the specific characteristics and the scalar modulation strategy of a new multi-level multiplexed inverter topology for medium-voltage AC applications. The proposed power converter configuration is intended for high-power applications aiming to reduce the active device's voltage rating and losses exhibiting a resulting low switching frequency of the power switches. The proposed modulation strategy aims to reduce the computational burden and simplify the implementation process, which are at the basis of any possible industrial adoption. Simulation results and full Hardware-In-the-Loop verification support the analysis. The Hardware-In-the-Loop assessment has enabled the development of a suitable modulation strategy, and the testing of the power converter is a safe environment.

Keywords

• Multilevel
• multiplexed
• AC application
• three-phase inverter