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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.

A two-phase alternator consists of two one-phase generators. The phase of the two output voltages of the alternator is shifted 90 degrees. The alternator rotor has a salient pole configuration without coils. Two generators are mounted in the stator slots inside the alternator stator. Each of the generators consists of one winding for excitation and one output winding for voltage generation. For generator excitation, DC or AC current may be used. For AC excitation, the direction of current flow is changed as a function of the rotor position. If three one phase generators are used with a 120 degree output voltage phase shift, then a three-phase alternator can be built. The two-phase alternator has simpler construction and less parts than a three-phase alternator and is consequently easier to fabricate and maintain. This paper presents experimental and the field circuit calculation results of two-phase alternators with DC and AC stator excitation.

The report provides an explanation of structure, functions and main components of optimum automatic DC micro engines system projection with excitation by constant magnets, used for a drive of antenna and glass hoist in modern cars. The construction optimization is made by several criteria. The length of the armature, number of slots, cross section area of slots, height of the magnet frame, diameter and number of armature winding turns, which are factored into the optimization process and provide the required mechanical characteristic of the motor. The presented CAD is realized in connection with visual object-guided programming of Borland Delphi.

The operation of electric vehicles in urban conditions, especially in limited spaces, frequently imposes increased requirements on maneuverability. For electric vehicles operating on roads up to 30-40 km/hour, one of the most practical methods of increasing maneuverability is the use of completely independent drawing mono-blocks. These blocks are self-contained units each consisting of a draw wheel, electric motor, power supply, storage battery, and an electronic power converter. The blocks allow the vehicle to rotate 360 degrees around center axis, turn at any radius, and move in any direction, including straight to the left and to the right. The authors have developed and patented an increased maneuverability electro-cycle vehicle which consists of two mechanically connected block modules. In addition to increased maneuverability, such a design also increases reliability-failure of one block module does not prevent vehicle operation.

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 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 actuator is the essential part of the automatic control system of the diesel crankshaft rotation frequency. The actuator on base of the linear electromagnet is considered. The purpose of this paper is to determine the conditions of receiving minimum of the weight and to optimize the parameters of the actuator. The exact calculation of the leakage of the magnetic flux and the parameters of magnetic circuit allows to find the characterisctics of the actuator precisely. In order to investigate the magnetic field in the axi-simmetric and planar complex shaped bodies such a stator and rotor of the electrical machines we have to solve Maxwell equations in these bodies. In this paper we use the Finite element method to calculate the magnetic field because it makes possible to avoid the dificulties connected with the complex shape of the system. The results of this paper allows to choose the material, configuration and parameters of the actuator optimally.