Electrical machine with two stators and two rotors - has excitation windings between stators and has mains voltage slightly greater than generator voltage for any load

摘要

The drive is for an electrical machine, which is equipped with two stators with polyphase widnings axially displaced relative to each other. The rotor consists of two cages opposite the respective stators. The excitation windings are located in the annular space between the two stators. The stators are fed from the mains and the excitation from a d.c. source. The voltage of the polyphase mains is from 1 to 3% higher than the highest voltage of the machine when functioning as a generator or irrespective of the value of the excitation current.