Modular multilevel converters (MMC) are one of the newly developed multilevel converters; the bridge of a MMC consists of several sub modules in series with independent DC sources. With increase of the number of sub modules, the space vector pulse-width modulation (SVPWM) of multilevel converters is getting more complex. This paper proposes a novel SVPWM generalized algorithm for arbitrary-number-level converters based on 600 coordinate frame; based on the PWM of two-level space vector, the transition matrix for action period between multilevel voltage vectors and two-level voltage vectors is derived based on 600 coordinate frame. And taking reducing switching loss and distortion of output voltage waveform as object, the method to choose redundant voltage vectors and the optimal synthetic sequence of voltage vectors are determined. And the reactive power compensation in power system which is based on MMC is introduced; the dynamic mathematic model is analysis. With the introduction of current feed forward control strategy and SVPWM based on 600 coordinate frame, the dynamic decoupling strategy and capacitor voltage of sub model with balance control is proposed. At last, simulation results show that the proposed algorithm is correct and extensible.