| Abstract: | The original instantaneous reactive power theory or p–q theory has been systematically used in the control of active power filters (APFs). When the APF is connected in parallel to a non-linear and unbalanced load, the p–q theory application has allowed a compensation strategy named constant power to be obtained. This means that, after the APF connection, the instantaneous power supplied by the source is constant and it has the same value as the average power consumed by the load. Nevertheless, the use of other compensation strategies is possible: unity power factor or sinusoidal and balanced supply currents, among others. This paper shows that any compensation strategy may be developed into the p–q theory frame. Besides, the paper presents a p–q theory reformulation without using mapping matrices, which makes easier the obtention of the compensation currents. Finally, an exhaustive analysis of practical cases has been carried out at simulation and experimental level through a laboratory prototype which has allowed the proposed approach to be verified. |
