Analysis of grid connected single stage flyback photovoltaic inverter

The zero-voltage switching (ZVS) concept for a grid-connected single stage fly back inverter is achieved by reactive current from the grid. A variable frequency control is used to maximize the amount of reactive current to achieve ZVS. Thus the bidirectional switches on the secondary side of the transformer have ZVS during turn-on that is achieved by the logical operator. By using the soft-switching concept the losses of the bidirectional switches are negligible. The switching of the primary side switch is achieved by grid negative current through secondary side bidirectional switches. The secondary side switches are triggered by the controlled output of the comparator which is taken by comparing the output voltage of the inverter and the grid side voltage.