Patent ID: 7663899

Claim:
An active compensation device connected between a power system supplying a dual-direction periodic current wave and a non-linear load operating in a first load regime and in a second load regime, wherein said second load regime said non-linear load requires a larger current for operation of said non-linear load than in said first load regime, the active compensation device, comprising: an electricity-storing unit; a bridge switching unit including a plurality of switches, wherein said bridge switching unit is electrically connected with the electricity-storing unit; and a controlling unit generating control signals supplied to respective control switches of the bridge switching unit, wherein the dual-direction periodic current wave supplied from the power system includes a first load current portion occupying a first portion of said dual-direction periodic current wave, and a second load current portion occupying a remaining portion of said dual-direction current wave, wherein, in said first load regime of said non-linear load, said controlling unit controls said bridge switching unit to pass said first load current portion to said non-linear load, and to store said second load current portion in said electricity-storing unit, and wherein, in said second load regime of said non-linear load requires a larger current than in said first load regime, said active compensation device produces a compensation current corresponding to said second load current portion stored in said electricity-storing unit, and supplies said compensation current, in addition to said first load current portion of said dual-direction current wave, to said non-linear load.