For improving the dynamic stability operation performance of voltage space vector STATCOM（VSV-STATCOM）

a kind of new double loop non-linear control strategy is proposed with consideration of uncertaintyofphysicalparametersexistedinthenon-linearmodel

external interference feature and with the use of the combination method of sliding mode control and the H

∞

control is proposed. The voltage deviation is taken as status variables and the slide mode variable structure control is adopted for the outer loop so to achieve stability of the sub-system. However

the active and reactive power variables are taken as status variables for the

inner loop and the linear H

∞

control is adopted to achieve interference suppression and finally achieve non-linear robust stability of voltage space vector STACOM. It is shown by the simulation and experiment result that in case of sudden change of reactive power compensation and big deviation of physical parameters and in comparison to the traditional forward decoupling vector control method

the overshoot of the reactive compensation capacitor terminal voltage is reduced significantly

the harmonic content of the reactive power input current is reduced

the efficiency of the VSV-STATCOM is improved

which has remarkableresultinsuppressingstabilityperformancereductionduetotheoffsetofphysicalparameters.