Electric machine with combined excitation in transport

One of the factors of the electric rolling stock competitiveness of any type of transport is the amount of energy consumed by its electric drive for transporting passengers. During movement, most of the energy is consumed as a heat energy loss in electric traction machines. It is especially important to reduce energy losses in the drive of vehicles with an autonomous power plant. In order to reduce losses in the mechanical part of drives and to increase reliability of their work, it is advisable to use an individual electric drive for each wheel of the rolling stock running gear, especially rail vehicles. In the electrical part of the drive, most of the energy loss is due to the traction motor. Electric motors with the rigid electromechanical characteristic are known to be most suitable for electric traction. These include electric machines with a combined excitation system, which can significantly increase their efficiency and reduce energy consumption by regulating the magnetic field of the machines. The article discusses one of the options of this kind of machines.