A machine parameter measurement of switched reluctance machines with egg-shape diagram

In this paper, a method for the machine parameter measurement of switched reluctance machines is proposed. Inductance variations with respect to the rotor rotational position are approximated with only a sinusoidal function and a constant. The machine parameters are the amplitude of fundamental component L₁ and the constant L₀. The ratio L₁/L₀ can be a performance index, which is close to 1 if the machine has better saliency. It is possible to measure these parameters in experiments. A series of input powers P_i and apparent powers S are measured by a digital power meter while applying square waveform voltages and changing the voltage phase angle. These measured points are plotted on a P_i-S diagram. An egg-shape theoretical curve is drawn with the least square method to find the machine parameters. Several test machines are experimented upon. It is found that machine parameters can be measured by the proposed method. It is also found that the performance index has a good correspondence with measured efficiencies