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Low-pass filters have been used widely in the supervisory energy management controllers (EMC) for electric vehicle applications. However, there has not been a comprehensive methodology for the selection of their key design characteristics, such as the passband, stopband, and attenuation capabilities. In this article, a novel, step-by-step procedure, for the design of the digital low-pass filters (DLPF) is presented for the EMC. Mathematical models for a generalized battery/supercapacitor (SC) structure are derived for the impedance functions of the system. These impedance functions are used to investigate the behavior of the sources and the converter in the frequency domain. Moreover, using the extracted information from the frequency response curves, the guidelines for design of the DLPF are presented. In addition to the DLPF, a fuzzy logic controller is developed to monitor the state-of-charge (SoC) of the SC bank to ensure its operation in a safe region. The controller is designed and tested for the Urban Dynamometer Driving Schedule, using MATLAB/Simulink. Finally, the theory and simulations are validated using a Typhoon hardware-in-loop real-time emulator.

This paper introduces a generalized platform for the design selection of multilevel inverters (MLIs) topologies for any industry, especially in low- and medium-power applications. This platform is novel as it combines the component count and stress in any MLI in a normalized unique score. Each MLI topology is designed to match specific criteria to meet a specific application, which introduces diversified sets of merits and demerits in each case. Therefore, choosing a suitable MLI topology for the specific application is rather a difficult, time-consuming, and complex process. Moreover, the comparison can only be conducted between MLI topologies that fall under the same category. This paper introduces a comprehensive study to propose a new benchmark (BM) which can be used to compare MLI topologies regardless of their constructions or oriented applications. Each MLI topology gets a BM score based on comparative factors that evaluate its components quantitatively and qualitatively. Thus, comparing different types of MLI topologies is a simple process of comparing their calculated BM scores leading to better well-informed choice. First, the proposed BM-derived forms are discussed. Then, the proposed methodology is illustrated by applying to various types of MLI topologies including conventional and recently introduced ones.

This paper introduces a unique quantified study about using low-losses fast-switching wide bandgap (WBG) devices, i.e., gallium nitride (GaN) and silicon carbide (SiC), over traditional Silicon (Si) devices in the switching of dc/dc converters, focusing on electric vehicles’ (EVs) machine drive and battery charger. A detailed model of the power train of a Nissan Leaf was developed in PSIM software, with WBG semiconductors’ capability. The model was simulated one time using GaN semiconductors and another time using SiC devices. Simulation results are quantified and a comparison between different semiconductors in terms of total losses and efficiency is presented. The developed PSIM model can also be extended to other EVs like Chevy Volt. A proof of concept prototype for a Nissan Leaf dc/dc converter was built in the laboratory and results were collected. Componentwise experimental results are presented and their correlation with simulation findings is demonstrated. In addition, experimental results of the overall power train test bench are found to be matched with the simulation results on a system level as well.