Design and Implementation of a Sine-Wave Inverter using Microcontroller with Modified Pulse Width Modulation Technique

Due to constantly increasing demand and generation gap, the people of Bangladesh are constantly facing load shedding. Additionally, because of rising fuel prices in the international market, the cost of power generation is increasing. This research proposes a cheap but effective modified sine wave inverter for photovoltaic systems. The harmonics performance of this proposed model is much better than traditional push pull inverter. A feedback system is included for low voltage recovery in output. This system also employs a high voltage protection system, low voltage protection system, overload protection system, low battery protection system, etc for the inverter’s safety purpose. From the simulation result, it is seen that the total harmonics distortion (THD) of this inverter is around 56.11% but by inserting a small LCL filter, this THD value reduces to 0.08%. A single-phase laboratory prototype is then developed to ensure the simulation results are accurate and the proposed topology can be implemented successfully.