Abstract— The proliferation of highly sensitive power system equipments demand high quality power supplied by utility. Hence power quality has been very interesting research area for past many years. Current harmonics are one of the most significant power quality issue, which is usually resolved by using shunt passive filters or shunt active filters. In this paper ICOSφ algorithm [3] based shunt active filter is implemented in analog circuit and tested for a nonlinear load. The test results show that it can compensate for current harmonics. The algorithm was implemented digitally by dsPIC 30F 4011 microcontroller with help of MPLAB C30 Compiler.