basic circuit scheme of modern inverters (power inverters)
Modern inverters (power inverters) use the basic circuit scheme like that shown in Figure 1.
As you can see from the figure below, direct current (DC) from the battery is converted into alternating current (AC) very simply, by using a pair of power MOSFETs (Q1 and Q2) acting as very efficient electronic switches. The positive 13.8V DC from the battery is connected to the centre-tap of the transformer primary, while each MOSFET is connected between one end of the primary and earth (battery negative). So by switching on MOSFET Q1, the battery current can be made to flow through the 'top' half of the primary and to earth via MOSFET Q1. Conversely by switching on MOSFET Q2 instead, the current is made to flow the opposite way through the 'lower' half of the primary and to earth.
Therefore, by switching the two MOSFETs (Q1 and Q2) on alternately, the current is made to flow first in one half of the primary and then in the other, producing an alternating magnetic flux in the transformer's core.
As a result a corresponding AC voltage is induced in the transforme's secondary winding, and as the secondary has about 24 times the number of turns in the primary, the induced AC voltage is much higher: around 650V peak to peak.
