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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 use of alternating current machines of a simple construction with the squirrel cage rotor or the soft iron salient pole rotor as a car generator allows to increase a reliability of a generator and the maximum rotor rotation frequency as well in comparison with synchronous machines. The main feature of a car generator operation is a wide range of a rotation frequency change (five or six times). The use of alternating current machines aforementioned with the capacitor excitation is impossible, because it requires a capacitance value change in a wide range. In the paper presented the rotor excitation by passing current impulses through the stator winding over necessary periods of time is considered. The possibility of such an excitation is confirmed by the experiment. The single-phase generator with external rotor excitation is analysed on the basis of a digital model.

The main feature of the described sensor is its contact-less construction. The lack of contacts on the moving rod increases reliability of the sensor. The sensor comprises the core with the short - circuited two - layer secondary winding. In addition, the sensor is provided with the two multilayer windings, the first being the long primary winding, the second one is the short output winding. The output signal is induced on the output winding. In order to produce the output signal, the alternating voltage with frequency of 20…50 kHz is applied to the primary coil. Depending upon the core position of the short-circuited winding, the current of various values will be induced, which causes various voltages to be induced on the output winding. The position of the core may vary in range 0...40 mm. The range can be modified in a particular construction. The output characteristics of the sensor are roughly linear.

The application of the induction electrical generator instead of the synchronous ones in the self-contained power diesel-generating plants is known to have a number of advantages. The induction generator is a simple and reliable non-contact electrical machine. The symmetric rotor possesses perfect damping features being of great importance with the asymmetric load. When operating with the frequency converter (amplifier) the generator is not loaded with the highest harmonics which makes it possible to lower the dimensions power by a factor of 1.5-2. The capacitor system is considered to be the simplest one among the available systems for voltage excitation and control. The paper considers the mathematical model of the two-phase induction machine. The model regards the residual magnetization of the magnetic circuit as well as its saturation in the nominal conditions.