Power minimization technique for induction motor load test

This paper presents the technique of how to minimize power from the supply when a three-phase induction motor is under the load test. The load test enables the determination of the value of load power, current and power factor of the induction motor. In practice, a DC generator or eddy current brake is applied for the mechanical test. The objective of this paper is to propose a load test method using two pulleys for changing speed of an induction motor. The second induction machine is controlled to operate as an induction generator in order to transfer the energy to the supply, therefore the power required during the test is obviously reduced. The study of how to control the induction motor operated as generator will be the useful information for developing the induction generator system (IG) to work with variable speed and load, and to make it work as a stand alone generator