Physical laboratory model of typical load torque characteristics for teaching electric drives

The realization of different load torque characteristics in the laboratory for the purpose of teaching electric drives is presented. The torque characteristics with linear and quadratic dependence on speed are achieved by mechanically coupling the induction motor with a DC generator connected to a resistor. By controlling the excitation current of the DC generator depending on the measured speed the desired torque characteristics can be achieved. This laboratory setup replaces the actual loads like centrifugal pumps, fans or brakes based on viscous friction.