Design and Analysis of a 75 kW Five-Phase Two-Switch Buck–Boost Converter for Photovoltaic Systems

This paper presents a five-phase, two-switch buck-boost (5P-TSBB) converter rated at 75 kW, intended for photovoltaic and energy storage applications that require a wide operating voltage range. The proposed system operates with photovoltaic input voltages ranging from 250 V to 1000 V and regulates the DC-link voltage between 600 V and 950 V. The converter supports two distinct operating modes: an independent multi-input mode for multiple independent input sources and an interleaved mode for a single high-power input. The feasible operating area of the converter is determined in the Vin–Vout plane, taking into account voltage, current, and power limitations. Simulation results and experimental investigations on a laboratory prototype, including measurements of efficiency and power losses, support the theoretical considerations.