The negative environmental impacts of energy production from gas and fossil fuels are causing widespread concern to developed countries. However, electricity production from wind turbines and solar energy systems is evolving rapidly to meet the demand for clean and renewable energy. Integrating renewable energy sources with power conversion systems is an area of intense research. Among possible alternative energy resources, solar photovoltaic (PV) systems are increasingly used for electric power generation because they are eco-friendly, emission-free, and relatively cost-effective. High-gain converters are an essential component utilized mainly in low-voltage renewable energy sources and dc-distribution systems because they provide a high-voltage gain and are more efficient than other step-up converters. Interleaved high-gain dc-dc converters promise efficient energy conversion across a range of applications, including distributed generation and grid integration. This paper presents a performance analysis of an interleaved high-gain dc-dc converter for dc-distributed renewable energy systems with 650 V GaN HEMTs. The converter design with GaN power transistors and SiC Schottky diodes is discussed. The performance of the high-gain converter is examined at different input voltages and output power levels.
DC microgrids are gaining significant attention for smart distributed power systems, particularly in commer- cial and residential sectors, because of their increased energy efficiency, improved power quality, and reduced generation cost. In DC microgrids, distributed renewable energy sources, such as wind turbines, photovoltaic (PV) arrays, and fuel cells, along with energy storage systems–batteries and ultracapacitors–are increasingly implemented as a method of sustainable and clean power generation. Power electronic converters, especially bidirectional buck/boost topologies, play a major role in interfacing these renewable energy sources and energy storage systems with the utility network. However, most existing bidirectional converters face serious conduction and switching losses caused by conventional silicon (Si) devices, which are reaching their theoretical and oper- ational limits. Wide bandgap (WBG) semiconductor devices, such as silicon carbide (SiC) and gallium nitride (GaN), are not only exceed the current Si devices’ limitations but also provide great potential for improving power converters. This paper presents the impact of cascode GaN power devices on a bidirectional DC–DC buck/boost converter in DC microgrids. The results reveal that cascode GaN power devices considerably im- prove the converter performance and efficiency at various switching frequencies, junction temperatures, and output power levels.