The utility model discloses a compound circuit of the functions such as rectification, active power filter and dynamic braking that have integrateed, including rectifier unit, active power filter and reactive compensation unit, clamp circuit, first state selects static switch and second state to select the static switch, rectifier unit selects the static switch to be connected in the interchange side with active power filter and reactive compensation unit through first state, connect in the direct current side through clamp circuit, the second state selects the static switch to connect between the three -phase AC brake resistance and active power filter and reactive compensation unit externally, clamp circuit connects between active power filter and reactive compensation unit and dc bus, provide the return circuit for the energy regeneration. The utility model discloses can carry out better compensation to the humorous reactive current of involving that diesel generator imported in the power, produced energy is released in the time of applying the brake boring winch (or locomotive) again, and partial energy can also feed back to other loads through the APF circuit to be used, has improved the utilization ratio of device.