Design and development of a grid tied solar inverter

In this paper a microcontroller based grid tied solar inverter (GTSI) has been designed and developed. Keeping in mind that solar PV power is expensive MOSFET switching has been used for higher DC to AC conversion efficiency. Here, PIC16F88 microcontroller has been used. In order to synchronize the output voltage of the inverter with the Grid voltage, sinusoidal reference voltage for the microcontroller has been taken from the grid line. The microcontroller generates PWM signal which is modulated by the grid voltage. Solar PV power is stored in a 24 V lead-acid battery which can be replaced by using maximum power point tracker. Solar DC power from the battery is feed to a switching circuit which is driven by the PWM signal. The output of the switching circuit is applied to the primary of a 500W step-up transformer. Finally, the output of the step-up transformer is filtered by a capacitor.