IEEE Access (Jan 2024)
Model Predictive Control for Single-Stage Three- Phase Split Source Inverter With Enhanced Switched-Inductor Configuration
Abstract
Power conversion systems need to meet various criteria, such as achieving optimal efficiency, minimizing costs and intricacy, and frequently enhancing boosting capabilities. This is commonly achieved through the utilization of a DC-DC boost converter (BC) at the front end preceding the inversion stage, resulting in a dual-stage structure. Conversely, single-stage power conversion systems, which integrate boosting within the inversion stage, provide potential benefits by simplifying system intricacy and reducing overall volume. Among various proposed alternatives, the split source inverter (SSI) has lately emerged as a viable replacement, presenting distinct features over the widely utilized Z-source inverter (ZSI). The boosting advantage of the SSI is comparable to that in the traditional BC, whereas it has been enhanced in numerous studies, particularly within impedance converters. This enhancement is essential for inverters with heightened voltage amplification is required, particularly when managing lower output voltage levels. To enhance this boosting function even more, a switched-inductor SSI (SL-SSI) has been created, substituting the conventional inductor with a switched-inductor within the SSI design. This paper investigates the performance of the SL-SSI using finite control set model predictive control (FCS-MPC) to validate the structure ability in providing high output-power quality. The suggested controller employs a discrete-time model to forecast input and output current behaviors for every switching state in the future via cost function reduction. The system’s performance has been evaluated using MATLAB SIMULINK and validated with Opal-RT OP 4510. The system underwent exhaustive evaluation, analyzing step changes and varied load power conditions from 0.1 to 7 kW. The system results confirm a notable boosting capability, with observed increases up to tenfold supported by mathematical analysis for higher multiples. Furthermore, the controller exhibits rapid reference tracking, achieving settling times of around 10 milliseconds for input current and negligible for output current. Significantly, the system excels in generating high-quality output power, meeting low total harmonic distortion (THD) limits, which reach levels below 0.45% in the output current. Additionally, two comparative studies have been presented, assessing both the inverter structure and the control technique behavior.
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