Working of D.C to A.C Inverters: Electromagnetic induction is the main underlying principle in the working of the dc to ac inverters. The Transistors Q1,Q2 and the Transformer T1 determine the power output of the inverter. The bigger the Transformer and more powerful the Transistors the more power output is obtained. The inverter requires steady supply of current which is provided by the Lead-Acid Batteries(as it operates at high wattages).
The inverters use electro mechanical switch, to immediately switch to the mode of discharging circuit of the inverter as soon as there is a power cut. This technique uses electro magnetic force to either make or break the circuit, i.e to switch it on or off.
Within the Transformer, there are two coils namely primary and secondary coils. Number of turns in each of these coils is significant. let the number of turns in and e.m.f of the primary and secondary coils be N1,E1 & N2,E2;
Then they satisfy the relation : E2= -(N2/N1)E1 On the basis of the above relation,the voltage output is determined.
NOTE: Tantalum capacitors are used instead of other capacitors because they do not have regular electrolytes which possibly over heat and explode.
References: http://www.aaroncake.net/circuits/inverter.asp GOOGLE images.