In this thesis, the performance an‎d control of a three phase Vienna rectifier are investigated with the objective of widening its power factor operating range while maintaining input power quality. First, the baseline configuration—including carrier based an‎d space vector modulations, conventional switching, an‎d the current, voltage, an‎d voltage balancing control loops—was designed an‎d implemented under unity power factor conditions. The power factor range was then extended to cover both leading an‎d lagging operation. Under these conditions, a rise in the input current total harmonic distortion (THD)—especially in leading power factor mode—was observed. To mitigate this challenge, modifications were introduced to the modulation scheme, switching strategy, an‎d control architecture. These improvements comprise optimized switching patterns to reduce distortion, the addition of a resonant controller, an‎d a low pass filter in the current control loop. Simulation results demonstrate that the Vienna rectifier equipped with the optimized control an‎d switching structure can deliver stable operation across a power factor span from 0.9 leading to 0.9 lagging, achieving THD levels acceptable under international stan‎dards while simultaneously acting as both a rectifier an‎d a reactive power compensator.

حميدرضا كارشناس

محمد سعيد مهدوي , فاطمه زارع