Three Phase Motor With DC Stator Excitation for Electrical Vehicle Application 2004-01-0357
The three phase electrical motor contains three armature stator coils shifted in space from each other 120 degrees and one stator coil for excitation. Salient multi poles laminated rotor without coil. Rotor has reduced weight because it does not contain coil excitation and has reduced steel core weight. Each of the armature coils is controlled by the one phase H – transistor bridge circuit. DC shoulder of each bridge is connected to a battery.
There is an optical sensor of rotor position which controls transistor bridges.
Rotor speed may be controlled by change of the armature voltage or by change of current excitation. Current value in both cases is controlled by a pulse-width voltage modulation.
In this type of machine, like in DC machines, it is possible to realize shunt, series and combinational methods of the excitation. It is known that series DC motors can develop very high torque at low speeds and therefore can serve very well in a vehicle applications. That is why this type of electrical machine with series excitation can be recommended for an electrical vehicle applications.
A physical model of this type of machine is performed on the base of the modified cur alternator. Principle of operation and physical model test results will be discussed in this report also.