This paper presents the design and analysis of single phase Power factor correction (PFC) using DC-DC Single Ended Primary Inductance converter (SEPIC).The proposed system applies cascade approach where outer loop is implemented with Particle Swarm Optimization (PSO) tuned PI controller to synchronize the output voltage with reference voltage and inner current loop is controlled by Bang-Bang/PSO based Fixed PWM control techniques. The performance characteristics of these two approaches are analyzed by simulation results. The PSO based Control strategy yields an advantages of unity power factor (UPF), low percent THD(%THD), well synchronized output voltage for the variations in the line and load. It also provides efficient tracking of reference voltage compared to Bang-Bang control.