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The electric drive with the synchronous electrical machine of independent excitation differs by high specific parameters, adaptability to manufacture, simplicity of a design, and reliability. These properties of the electric drive allow using it in heavy conditions of operation. In particular, it can be recommended to use in electrical vehicles. The electric motor for this electric drive can be executed with two separate stator windings. Therefore, there are additional benefits connected to an opportunity of change of geometry of an iron stator stamp of the given type motor. In this report, the principle of operation of the electric drive with control system is considered. The different variants of a stator design of the electrical machine are discussed. The stator design allows improve of the mass and weight parameters of the electric machine. For the offered stator designs, the comparison of specific parameters (relationship of the nominal torque to load current) is carried out.

Power field effect transistors are used and will be used in almost all automotive systems. Control of field effect power transistors requires isolated 5V control signals and isolated 12V DC sources. The first problem is resolved by using optical pairs: light emitting diodes with phototransistors. The second problem can be resolved by using impulse voltage sources. The primary coil of a transformer is connected to the battery by a transistor switch. In the first period of operation of this voltage source, the energy is stored in the magnetic field of transformer’s inductance. In the second period, the energy is delivered to the output voltage source. Energy is delivered from the secondary transformer’s coil to the output capacitor through a diode.

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.

This paper describes the generator's principle of operation, experimental characteristics, and compares it with other types of generators. As a rule, motor vehicle generators operate under severe conditions, therefore mandating brushless operation as a design requirement. Brushless generators, designed on the basis of synchronous machines with stator independent excitation, have high specific power parameters. In generating mode, the synchronous machine with stator excitation possesses certain features and advantages which are considered in the report. It is shown, that it is necessary to divide circuits of output windings and windings for excitation, which in turn allows simplification of the power circuits and the excitation converters. The output winding circuits can be executed for operation with a three-phase bridge rectifier. For feeding of the excitation circuits, use of half wave structures is proposed.

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 results of theoretical and experimental investigations of the special synchronous machine and the electrical drive on its base are submitted. This paper covers the principle of operation the brushless synchronous machine, its experimental characteristics, comparison with other types of motors, technique of account of the electromagnetic torque, functional circuits of the electric drive with the independent excited synchronous reactive motor (FRRM - Field Regulated Reluctance Machine). It is the most favorable application of the considered electric drive in the vehicles with heavy conditions of operation, where such are urgent it advantages, as: brushless, high rigidity of the shaft, large overloads on the torque. It can be used in the regular cars for starter generators, in pure-electrical and hybrid-electrical vehicles for power drive, in independent power generating installations with high-speed of the gas turbine engine and so on.

In this paper we consider the questions of increasing the between-charge mileage (range) of electric vehicles and other vehicles with independent electrochemical power supplies. These are classified as hybrid vehicles, and can have various combinations of energy sources installed, such as: storage battery and electrical generator, driven by the engine, storage battery and solar panel, capacitor and electrical generator with engine, and others. The priorities for the development of the combined power supplies used now are considered and analyzed. On the basis of the power analysis of the combined power supply of the hybrid electro-mobile with a solar battery - of which the basic source of energy is the storage battery - the technique of defining the length of between-charge mileage of the vehicle is developed, depending on a combination of a set of parameters: both the components of the combined power supply, and the parameters of the electrical vehicle.

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.

This generator is a new simplified design version of an alternator with DC stator excitation that was published by the authors in the SAE 2003 and SAE 2004 World Congresses. [7, 8] In automotive applications, this type of electrical machine may be useful for regular cars, hybrid and fuel cell electrical vehicles with an electrical power source system of 12 VDC, 24, and higher. Brushless car alternators with DC stator excitation have less rotor inertia because the excitation windings are located in the stator. Smaller rotor inertia eliminates drive belt slippage. This generator is more reliable in view of the absence of contact rings and graphite brushes in a rotor circuit, which exist in a standard claw-pole alternator [9]. The laminated salient pole rotor of the alternator is very simple in construction and has low cost of production. The two-phase alternator is simpler than the three-phase, as it has only two output windings instead of three.

The electrical power consumption in automobiles continues to increase thereby demanding higher power capability of the alternator. The standard alternator today is a claw-pole synchronous machine. The claw-pole alternators have brushes which are maintenance issue; it is not possible to increase power output by increasing the stack length; and the rotor inertia is large due to the steel core and rotor excitation coil. Despite these disadvantages, the claw-pole alternator is still used because of its low cost and ease of manufacturing. An alternator with DC stator excitation, has a laminated salient pole rotor with no excitation coil. Therefore the weight and inertia is less than in the claw-pole alternator. The excitation coil is located in the stator and therefore there are no brushes needed. In this type of alternator, the stator has three-phase output coils evenly shifted in space 120 degrees.

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.

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.

The relay control is known to permit the design of the control systems invariant with respect to outer disturbances. The features of the offered method include the relay control for each state variable and the changing value of the output signal of the relay element. To improve the electronic controller of the diesel rotation frequency a number of variants for developing the scheme structure of controlling the fuel feed in the diesel with high pressure pump are considered on the basis of digital model. In introducing feedbacks of all state variables the structures realized by means of analog (proportional) and ralay controllers were compared.

The design of the electronic fuel feed control system on the D-160 tractor diesel as well as its features and the prinicples of operation are presented in the paper. The preliminary bench and field tests on the T-170 tractor, the system passed, revealed its advantages.