Scalar Control of Single-Phase Induction Motor Using PV Fed Modified Seven Level H-Bridge Inverter with Improved Sinusoidal PWM Technique

Abstract

Scalar Control of Single-Phase Induction Motor Using PV-Fed Modified Seven-Level H-Bridge Inverter with Improved Sinusoidal PWM Technique" proposes an advanced modulation technique for controlling a modified H-Bridge solar photovoltaic (PV) fed seven-level inverter, designed to drive a single-phase 230V, 1/2 HP capacitor start-run induction motor (IM). This paper introduces an innovative H-bridge seven-level inverter topology achieved by optimizing the number of switches necessary to generate seven distinct voltage levels. The induction motor's speed is regulated using a scalar control approach. Pulse width modulation (PWM) signals, crucial for controlling the switches in the seven-level inverter, are generated using a combination of three identical sine wave signals acting as reference signals. These signals have an offset equal to the amplitude of the triangular carrier signal. The proposed modulation technique is validated through simulation in the MATLAB/Simulink® environment. Results demonstrate that the seven-level inverter efficiently suppresses harmonics by over 50% compared to three and five-level inverters without the need for an external LC filter. Additionally, the proposed technique significantly reduces the voltage stress across switches by 35%, even with a reduced number of switches utilized.