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This paper proposes a generalized Gallium Nitride (GaN) based modular multiport multilevel flying capacitor architecture. In other words, the attractive flying capacitor multilevel (FCML) design and the full-bridge unfolding circuit are employed to develop a multiport multilevel converter architecture that fits various applications. Each module can be designed to contain any combination of AC and DC ports connected through DC-to-DC and DC-to-AC power conversion paths. These conversion paths are FCML topologies that can be designed with any number of levels; the DC-to-AC paths incorporate the full-bridge unfolding circuit. Two example prototypes with open-loop control, three-port and four-port, have verified this generalized architecture. A single module 3 kW three-port four-level prototype with two DC ports and an AC port has achieved a compact size of 11.6 in 3 (4.8 in ×4.3 in × 0.56 in) and a high power density of 258.6 W/in 3 . The three ports are connected through DC-to-AC and DC-to-DC paths that have achieved peak efficiencies of 98.2% and 99.43%, respectively. The total harmonic distortion (THD) of the AC port's voltage and current are 1.26% and 1.23%, respectively. It operates at a high switching frequency of 120 kHz because of the GaN switches and has an actual frequency (inductor's ripple frequency) of 360 kHz thanks to the frequency multiplication effect of the FCML. The four-port prototype contains three DC ports and an AC port and achieved similar high figures of merit. These experimental results of the two prototypes of high efficiency, power density, and compact size are presented in this article and highlight this architecture's promising potential. The choice of the number of modules, ports, and levels depends on the application and its specification; therefore, this proposed generalized structure may serve as a reference design approach for various applications of interest. 

The size, weight, power density, cost, and efficiency are crucial factors that should be considered when designing or employing power electronics converters for a specific application. Therefore, comparing different converters to investigate which converter provides better figures of merit at the same application and operating condition is essential. This paper uses theoretical, simulation and experimental comparisons between the two-level and multilevel converters. The DC-DC two-level buck and the flying capacitor multilevel (FCML) buck converters are chosen to carry out the theoretical, simulation and experimental prototypes when both employ Gallium Nitride (GaN) power semiconductor switches. It was found that the FCML converter inherently provides superior performance and figures of merit over both the two-level and multilevel converters. Simulation and experimental results that validate each other are provided in this paper. 

Electric Vehicles (EV s) that are wholly charged from renewable energy resources to avoid indirect emissions are the most effective solution for climate change and energy insecurity. This paper proposes a four-port isolated PV -based EV charging architecture that contains an LLC input stage to harvest solar energy with high efficiency because of its dual PV input ports with independent MPPT capabilities that share a common resonant tank. This architecture also includes a GaN -based flying capacitor multilevel (FCML) output stage with two GaN-based FCML converter paths, DC and AC paths. These two paths transfer power with high efficiency to two output ports, a DC port for direct DC charging and an AC port for level-2 AC charging. The system has been verified by building a 2 kW prototype module, and experimental results are presented. 

A three-port multilevel inverter with two DC ports and an AC port using Flying Capacitor Multilevel (FCML) design based on Gallium Nitride (GaN) switches is proposed in this paper. Recently, FCML inverter has shown a superior ability for power conversion with high power density, improved Total Harmonic Distortion (THD), and efficiency. The presented three-port multilevel inverter fits various applications such as battery and photovoltaic (PV) grid integration and standalone AC load. The proposed inverter is experimentally verified by building a 3-kW prototype using GaN switches which include two 4-level FCML converter paths, each share the same bus capacitor (C bus ), which links them together. One FCML path is 1 kW that incorporates an unfolder for the DC-to-AC conversion and has achieved a peak efficiency of 98.2% with AC voltage and current THDs of 1.26% and 1.23%, respectively. While the second FCML converter path is 2 kW used for the DC-to-DC conversion and has achieved a 99.43% peak efficiency. 

Purpose This paper addresses the significance of training students in entrepreneurship to enable sustained national and international competitiveness in the knowledge-based global marketplace. Entrepreneurial education is varied, ranging from basic to in-depth courses, including customer-focused programs, such as the National Science Foundation (NSF) sponsored Innovation Corps (I-Corps) program. This program is nationally-renowned with strong academic roots. A full site was launched at the University of Central Florida (UCF) in January 2015 and was the first I-Corps program in the state of Florida. Design/methodology/approach This paper addresses the importance of entrepreneurship education, reviews the available national training programs in entrepreneurship, presents the design methodology of the NSF I-Corps program, and analyzes the results of the teams who have participated in the NSF I-Corps program. Findings The results are categorized into innovative areas and show the percentage of teams who participated in the I-Corps program in each area. It also identifies the percentage of teams who engaged in actual startup activities following I-Corps participation. Practical implications Educators, students, and trainers can use the findings to benchmark the outcomes of training programs in entrepreneurship. Students and innovators interested in participating in I-Corps can use this paper to obtain insights and a broader understanding of what was done in terms of results and implications. Originality/value This paper contributes a unique analysis of the I-Corps program approach and its outcomes since its launch in 2015 and can be used as a reference for any training program in entrepreneurship.