Harmonic analysis of average current control and sine PWM control for H-bridge converter with additional switch legs

This paper presents H-bridge converter which is bridgeless boost converter with sinusoidal pulse width modulation to improve the quality of utility mains ac supply. Due to nonlinear loads and common mode voltage harmonics are produced on the supply side which can be reduced using sinusoidal pulse width modulation technique for H-bridge converter. To reduce the common mode noise currents the grounds of input and output terminals are connected through common mode capacitor. A comparative study between average current control and sinusoidal pulse width modulation (SPWM) techniques for H-bridge converter is proposed in this paper. A comparison has been made in terms of total harmonic distortion (THD) level in the supply current. A closed loop control system has been designed for each control strategy and the converter is simulated using the MATLAB/SIMULINK The performance of the converter under each control strategy is evaluated. Finally, it is concluded that the sinusoidal pulse width modulation technique is more efficient than average current control to lower THD of current. It reduces THD nearly by 28%. This improves power quality and also reduces electromagnetic interference.