Considerations Regarding the Middle Power Asynchronous Motors for Railway Electrical Traction

In modern electric traction, direct current traction motors have been replaced with asynchronous motors with a short-circuited rotor. The justification is that asynchronous motors are more reliable, cheaper, and have smaller weights and dimensions, so they are more sustainable. In order to start and adjust the speed required in traction, these motors are powered from the contact line using a transformer and a static voltage and frequency converter. As a result, you can use green electricity produced with wind power plants or solar energy converted with photovoltaic panels, increasing sustainability because the consumption of traditional fuels is reduced. This paper presents various simulations emphasizing the negative effects of the distorting regime, with concrete results. The quality of the simulations carried out is increased by using a mathematical model, which uses the variable parameters of the motor dependent on the modulation of the current and the magnetic saturation. In modern 1500 kW electric locomotives, the traction motors are powered by static converters, which means an increase in losses when operating at nominal load on the motors by 38.7 kW and 217.8 kVAR compared to the sinusoidal three-phase power supply. Thus, the research carried out provides qualitatively and quantitatively correct simulations of the non-sinusoidal regime related to the asynchronous traction motor in order to increase the sustainability of this traction system.