you have to know something. 1. when the DC is 24V, the maximum output voltage(RMS value) is 20V so if you want a 220V voltage, you need to add a transformer. 2. IGTB inverter is not like the Thysistor, whose gate is fired with a certain angle. the IGBT gate pulse is a PWM wave. and there are some modulation method to generate the PWM, like SPMW, SVPWM.