Normally, high power voltage source inverters are very common in industry and need to provide sinusoidal output to the load for proficient operation. Sinusoidal wave output can be obtained in inverters by adopting various modulation techniques, which increases the switching frequency of the inverter elements like IGBTs and Power MOSFETs, which are having limited power handling capabilities. In case of moderate to high power output from the inverter, SCRs or GTOs need to be used as inverter switching elements. These devices are having limited switching frequencies making the inverter operation impossible using the high frequency modulation techniques. This results in an output with rich harmonic content. The latest multilevel inverters can be used to overcome these problems. But the circuit is very complex and also requires isolated power supplies to feed the inverter. In the proposed project, a low frequency square wave inverter using SCRs is operated along with a series connected pulse width modulated inverter, in each phase designed. The 3-phase SCR inverter basically works as a voltage source inverter producing square wave output. The series compensator used in each phase produce only the desired harmonic voltages to make the net output voltage sinusoidal, with small PWM switching harmonics only. The series compensators are designed using the IGBTs, forming a bridge inverter configuration.