The Basic Research Of Double-Rotor Electromechanical Energy Transducer

The double-rotor electromechanical energy transducer is a kind of multiple input and output electric machine with two electrical ports and two mechanical ports, it has received more and more attentions at home and abroad in recent years for its good ability in power transmitting in a multiple energy system, such as hybrid vehicles .Double-rotor electric machine could be implemented in divided or concentric structures, the divided has simply mathematic models and coupled mechanically only, while the concentric structure has both mechanical and electromagnetic couplings, its two magnetic circuits for outer and inner air gaps share inter rotor's iron core to form parallel or series flux paths, but in most cases should be general status between them. According to the magnetic couplings of the double-rotor electric machine, its equivalent magnetic circuits is presented in this paper, its equations for voltage, flux linkage, electromagnetic torque and motions are presented also.There is no fixed method for concentric double-rotor electric machine's design at present, because the magnetic couplings make it hard to calculate magnetic circuits accurately. For simplicity the author separated the concentric structure into two independent machines based on the divided structure's parameters, first step designed the primary machine composed of rotor and inter rotor, where the thickness of inter rotor should be reasonable, second designed the assistant machine composed of stator and inter rotor, whose main dimension came from the primary machine, finally calculated its electric and magnetic loads. According to this method the concentric concept machine based on induction motors has been designed and made.Some simulations has been made, When the machine worked in steady operation, stator and rotor magnetic forces interact themselves, so generated electromagnetic torque, its magnitude depends on the electric angles between the two forces, it is also affected by slots on inter rotor. The interaction between stator and rotor could not be neglected.Concentric double-rotor electric machine usually with plate shape has many...