This paper presents a new theory to improve and assess the quality of electrical power. The theory is based on the tensor product between voltage vectors and n-phase currents. This new definition allows the estimate of reference currents for the control of active power filters “APFs” in multiphase systems and also determines a quality deviation global indicator. In addition, the improvements (implementing an ideal APF) and the assessment (measuring the global deviation) of electric power quality are validated by means of a practical case.
