This is book use of proposed overview of the state of the art in reactive power compensation technologies. The principles of operations, characteristics and application examples of VAR compensators implemented with switches and self-commutated converters are presented. Static VAR compensators are used to improve voltage regulation, stability. The reactive power component is estimated from the reactive component of input current (Iq).In the proposed work 2-level and 3-level diode-clamped multilevel inverters are studied and then implemented for the applications of reactive power compensation and are simulated by using MATLAB/Simulink for various parameters like Active & Reactive power at load, Per unit input and output voltages. Tabulation can be made for Converter & Load, Active & Reactive powers.