The instantaneous power theory on the rotating p-q-r reference frames

This paper proposed the rotating p-q-r reference frames where one instantaneous active power p, and two instantaneous reactive powers q _q, q_r were defined in 3-phase 4-wire systems. The three power components are linearly independent, so that compensating for the two instantaneous reactive powers leads to control the two components of the current space vector independently. With the theory, this paper shows that the neutral current of a 3-phase 4-wire system can be eliminated by only compensating for the instantaneous reactive power using no energy storage element. Simulation results verify the theory very well