Basic H-bridge cascaded structure is adopted in cascaded-SVG.The issue of voltage balancing control existed in respective DC capacitor

due to direct series connection of unit

is the key of safe and reliable operation of the complete installations.The droop characteristics of DC power supply for H-bridge inverters is constructed by the author

on this basis

the balancing control method of DC voltage of multi level SVG is achieved

preliminary theoretical derivation for this method

simulation and application verification of ±4.33 Mvar cascaded-SVG is conducted and the effectiveness and feasibility of the method is proved

which provides basic assurance and perfect platform for the study and development of cascaded-SVG

at the same time

provides very important reference for other cascade power conversion devices.