Comparative evaluation of the methods of powering the PMSM in a thyratron motor mode

The article provides a comparative assessment of various ways of powering a synchronous motor with permanent magnets (PMSM) in the mode of a thyratron motor (TM). Numerically, on analytical and computer models, mechanical ω = f(M), the dependence of speed on electromagnetic torque, and energy ηэ = f(M), the dependence of electromagnetic efficiency are calculated from the moment, the characteristics of the motor with sinusoidal power supply and discrete switching with different values of the relative inductance of the winding. Moment pulsations are investigated. The three most common methods of discrete degree commutation are considered - 120, 180 and 150. It is shown that discrete 120 degree commutation provides the highest value of ηэ in comparison with other methods, and the mechanical characteristics are approximately the same in appearance with different power supply methods. The study of moment pulsations has shown that discrete switching without additional measures cannot compete in this indicator with the case of sinusoidal power supply, which theoretically has zero moment pulsations. However, the use of 150 degree commutation makes it possible to significantly reduce them, bringing them closer to 2…3 %. Curves are given that allow an approximate estimate of the expected moment pulsations for all discrete switching methods. Practical recommendations on the choice of the method of powering the PMSM are given.