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The performance and property of brush-less car alternator with gap flux controlled by DC stator coil is discussed in this paper. This type of alternator is more dependable, has reduced weight and dimension of rotor compared with traditional alternators. Reduction of the rotor weight is obtained by elimination of rotor coil and reduction of steel core weight. The stator steel core is laminated and exactly like ordinary stator core, but coils are different. There are three phase stator coils and coil for DC excitation. Salient multi poles rotor is laminated and does not contain any coils This paper presents theoretical discussion of principle of operation of this type of machine. Traditional alternator was modified for physical modeling. Results of this modeling are presented as well.

It is known, that the alternator self-excitation is possible at capacitor loading [1]. From this follows, that the alternator excitation by means of capacitors connected to one or several stator windings, as from simple excitation winding is located on a rotor, is possible. In the report the excitation of the automobile alternator with claw pole rotor by means of capacitors connected to stator windings at rotor open excitation circuit is considered. Thus, for comparison the alternator idle characteristics are received both at excitation by means capacitors, and by means of a simple excitation winding. Besides the other electrical parameters of the alternator with claw pole rotor by experimental way are determined. On the basis of the received data the alternator digital model was developed, it takes into account the magnetic circuit saturation, by using of the received experimental idle characteristics.

The new wireless rotor electrical machine has all the coils placed on the stator. The laminated wireless rotor serves as a magnetic field switcher. A wireless rotor is cold, and it facilitates machine cooling. The model of the wireless rotor machine includes electrical and mechanical components. The wireless rotor machines can find an application in practice because they have advantages over existing devices. In modeling, we use a new approach. We consider a motor as a natural control system with torque feedback. Such an approach simplifies analyses and adjustment of the operation of an electrical machine. First, we analyze an open-loop control system without torque feedback. In this case, by changing the rotor speed under external torque, we can receive the torque-speed motor characteristics. After some adjustments to the open-loop system, we can consider the close loop control system with torque feedback. We use a space vector representation for sinusoidal electric components.

In this paper, we consider a new design of synchronous motor with salient poles rotor and all coils placed on the stator. This design, uses a laminated silicon steel rotor, which is not so expensive as a rotor with super strong permanent magnets. This design of machine eliminates copper rings on the rotor and brushes which is used in regular synchronous motors, and eliminates disadvantages involved with these arrangements. In an earlier publication, authors considered the opportunity realization of synchronous mode operation in the machine with salient pole rotor and DC stator excitation. Now, we consider the new synchronous mode operation with individual DC excitation of each the alternative current (AC) windings for realization the first, second and third phase synchronous machines. In theoretical basics of analyses and design of synchronous motors we pay more attention to the single-phase motor because it is the basis for design polyphase synchronous machines.

The urban trams with a low floor are more convenient for the passengers, and with a high floor - more cheaply and more technologically during manufacturing and operation. The combined advantages those and others in themselves are trams with average height of a floor, but for this purpose it is necessary to lower height of tram carriages, that is reached by application of electric motors with a small stator external diameter. It is offered in this the perspective electric drive on the base of the synchronous motor with independent excitation. The salient rotor poles of the motor do not contain windings. The motors stator is carried out on the base of the stator body of regular AC electric motor. The multiphase winding is located in the stator. A winding section, which conductors settle down above the between rotor poles, carry out a role of the excitation winding, and others, which conductors lay above poles, - a role of the armature winding.