Comparative Analysis of DTC-controlled TSTPI and FSTPI Inverters for Low-power Photovoltaic Applications

The increasing global shift towards renewable energy (RE) has amplified the need for efficient and cost-effective DC/AC converters in photovoltaic (PV) systems. This paper focuses on evaluating the performance of reduced structure inverters, specifically the Three Switch Three Phase Inverter (TSTPI) and the Four Switch Three Phase Inverter (FSTPI), both operating under Direct Torque Control (DTC), for low-power PV applications. A novel DTC strategy has been developed and applied to the TSTPI to improve control precision and overall performance. Through extensive simulations in Matlab/Simulink, complemented by experimental validation on a dSPACE1104 platform, we assess and compare the operational efficiency, harmonic distortions, and electromagnetic torque oscillations of both inverter structures.The findings reveal that, while both the TSTPI and FSTPI demonstrate satisfactory results, notable differences arise in terms of efficiency and harmonic distortion levels. These results highlight the suitability of reduced structure inverters for low-power PV applications, offering an attractive balance between cost and performance.This study provides valuable insights that can guide future developments in the design and real-time implementation of inverter systems tailored for RE applications.