For the increase of capacity of active power filter（APF）and with the use of such feature of MMC converter as high withstand voltage grade and equivalent frequency

a kind of control method of MMC active power filter with twenty-four modules in three phases is designed

which designs the control strategy of capacitive voltage and assures stability of the capacitive voltage of the sub-model. At the same time

the indirect control algorithm of voltage is designed in accordance with the features of MMC so to keep the APF output the compensation current which is detected by i

p

-i

q

method and thus assures the current at the system side is fundamental positive sequence current. The method is simple in the control and is easy to achieve and its effectiveness is verified by the Matlab/Simul

ink simulation test.