Comparing low cost speed control for single phase induction motors concerning line reaction and electromagnetic compatibility

Low cost speed control of capacitor run single phase induction motors across a wide range of speed and load continues to be of interest. In the paper at hand the line reaction as well as the electromagnetic compatibility of three different methods for speed control - Phase Control, Integral (Half) Cycle Control or Integral Switched Cycle Control - is investigated. Measurements are carried out at different rotor speed and load torque, comparing the methods at approximately the same operating points. FFT is computed for the line currents and measurements on electromagnetic compatibility are presented as well. Subsequently, a method for lowering the induction machine current´s amplitude and the magnitude of the fundamental component of the line current by combining Integral Cycle Control with Phase Control is investigated, again concerning line reaction and electromagnetic compatibility.