Here’s a design circuit for SCR inverter circuit that is build using BSTC1026. If device is too heavy or if there is a short at the output, this requires some kind of protection, on the input line, in the form of a fuse or similar. This is the figure of the circuit;
The transformer used is a 10Watt mains type with 6Vdc+6Vdc windings on the SCR side and a 110V+110V windings, in series, at the output. Efficiency is 50% and the ideal load is equivalent to a 22k resistor, 5Watt. Output waveform is vaguely sinusoidal at a frequency of 400Hz.