This book contents an elaborate analysis on the SPWM (Sine Pulse Width Modulation) Boost Inverter especially for the grid connected PV power system. Reactive power control strategy of Boost Inverter at the inverter side has also been studied. By changing the modulation index of the Boost Inverter the output parameters have been varied. A range of modulation index has also been prescribed within which the percentage of THD (Total Harmonic Distortion)is in a tolerable range according to the IEEE standard 519. Moreover, a rigorous analysis on a set of different parameters along with the simulation results has been made and compared to investigate the proper characteristics of this device.