Energy-Efficient Operation of Industrial Induction Motors Exposed to Multiple Power Quality Disturbances

Induction motors (IMs) are the largest consumers of electrical energy across most industrial sectors owing to their widespread application. The power losses in IMs significantly depend on the quality of the supply voltage. The presence of various power quality (PQ) disturbances, such as voltage deviation, voltage unbalance, and voltage harmonics, may increase the power losses by over 60%, even if the PQ fulfils the standards. To ensure the energy-efficient operation of IMs, PQ standards should be modified. One possible solution is the implementation of a coefficient of voltage energy efficiency (cvee), which is proportional to power losses in IMs under PQ disturbances. In this paper, recommendations concerning the implementation of cvee in the relevant standards are formulated. Additionally, results of PQ monitoring are presented and values of cvee in land power systems are discussed.