Synchronous generator with two-channel excitation for power supply of railway passenger cars

In the paper, the authors consider the possibility to raise the specific power of the synchronous generator applied for supplying the railway passenger cars with electric energy. On the railways of Baltic countries and the states of the former USSR, in service are mostly passenger car generators of the inductor type with axial electromagnetic excitation (type 2ΓB.13). These electrical machines are too massive, costly in making as well as in operation and maintenance. It is proposed to basically modify the design of such a passenger car generator by devising, in addition to the electromagnetic excitation channel, an additional channel with excitation from reliable strontium-ferrite magnets which would be reliable in operation under elevated temperatures as well as resistant to vibrations and shocks. This design allows relieving the magnetic circuit of such a machine in its axial sections, reducing the mass of the regulating excitation winding and the total mass of the passenger car generator, at the same time raising its coefficient of performance (COP).