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The problem of increasing the accuracy of determining the torque and the load angle of the permanent magnet synchronous motor of an electric traction drive to the predicted level (2.5...3)% of the full-scale error is solved by an indirect method. We considered the algorithms for calculating the generalized current and voltage of the electric motor, the total power, the instantaneous values of the power factor, and the sine of the phase angle between the first harmonics of voltages and currents. We determined the requirements for the accuracy of determining these values at the level of 1% of the full-scale error. We considered the algorithms for determining the total instantaneous power losses by the indirect method at the predicted level (15...20)% of the full-scale error with the efficiency of the motor (90...95)%.

With the development of the market of electric vehicles, the issue of efficient battery charging becomes even more urgent. Thanks to the continuous increase in the level of development of electronics, new opportunities appear to create power electrical equipment with previously unattainable characteristics. For these purposes, a universal algorithm for fast charging of LiFePO4 batteries been developed. It assumes the fastest charging of the battery without damage due to overheating or overcharging. The algorithm includes several main parts: the algorithm of initial temperature testing, the algorithm of initial trickle charging, the main current charging algorithm, the algorithm of permanent temperature testing, the main voltage charging algorithm, algorithm of permanent temperature testing, the algorithm for final trickle charging. The efficiency of the fast battery-charging algorithm studied by mathematical modeling. Computer modeling carried out using open source software.

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.

DC motors are the most controllable electrical machines but more complicated for fabrication, in comparison with induction motors having simplified design but more complicated for control. Regular DC motor contain excitation (field) coil on the stator and armature coil on the rotor. Armature coil connected with external voltage source by a mechanical commutator with brushes. This arrangement complicates fabrication of DC machine, increases its cost, lowered reliability, and demands regular maintenance. Electromagnets inside of the stator increase dimensions of DC motor. In DC motor with salient pole rotor, there are no coils on the rotor, and mechanical commutator with brushes is eliminated, and eliminated all disadvantages connected with this arrangement. In this paper, we consider the new version of DC machine with DC stator excitation in compare with presented earlier. The difference is in using individual coil excitation for each armature coil, placed on the stator.

Linear electric motors designed on the basis of permanent magnets have disadvantage. It is caused by nonlinear distribution of a magnetic flux density around the cylindrical permanent magnet. Therefore, the motors should be designed with the high level reserve power. It lids to increase of mass - dimensional parameters of a motor. In addition, it complicates a control system of an electric drive on base of the linear motor. These disadvantages are eliminated by using, offered by authors, of three-zoned permanent magnetic structures. Using the three zone magnetic structures on basis Nd-Fe-B permanent magnets allows reducing weight - dimensional parameters of the linear motor. In this paper is considered design technique of creation the tree zone magnet structure. As an example, it was designed linear electrical motor (actuator) for diesel speed electronic controller. Prototype electronic speed controller was build and tested.

The purpose of this paper is to investigate opportunity to create a new type AC induction motor with the salient pole rotor (without winding) and both winding AC excitation and short circuited placed on the stator. There are some advantages in this design: The suggested design has a cold rotor. The stator short circuited and excitation windings are easier for cooling. The rotor has reduced weight in compare with regular induction motor rotor. The short circuit winding can be used for the current control like in the regular induction wound-rotor machines. In this case, the problem maintenance of the slip rings is eliminated. In this paper, we discuss theoretical opportunity for realization the induction mode operation in two and three phase machines. As a base for this, it serves the analyses operation of one phase machine. This analysis is fulfilled in comparison with regular induction motors with short circuited and wound-rotor windings.

The design of the injector tips is the primary factor of influence the fuel delivery system on parameters of a diesel engine. The location of the entrance edges spraying holes of injector tips is one of the most significant design data. In modern diesel engines, the injector tips are used with entrance edges of spraying holes are located in a volume of a cavity under a needle of an injector tip or on locking cone of the needle saddle. In this paper, the two different locations of the entrance edges of spraying holes are considered. Two real injector tips where selected for analyses and tests with different location of the entrance edges of spraying holes. The selected injector tips where modeled by using finite elements method and also these injector tips where installed on diesel and diesel characteristics where received. For selected injector tips, the three dimensional model of the injector tip parts was created.

The design of the inertial continuously variable transmission consists of the inertial pulsed mechanism with unbalanced inertial elements and two overrunning clutches. The inertial pulsed mechanism is well developed and possesses high reliability. The overrunning clutches are the least reliable parts of the transmission and limit wide application of the transmission. In this paper, a new design of the inertial transmission with only one overrunning clutch is proposed. This transmission provides a high level of the load capability. The object of the investigation is a structural dynamic analysis of the continuously variable automatic inertial mechanical transmission. The physical and mathematical models of this transmission are developed. For these models of this transmission the differential equations of structural dynamics in the form of second kind Lagrange's equations were developed. These nonlinear differential equations were solved on the basis of Runge-Kutta numerical method.

In transport applications, the synchronous motors are used for the power drives, because of their high operating efficiency, and controllable power factor. Brushless electrical machine with DC stator excitation have on the stator the armature and excitation windings. Rotor is a salient pole construction with laminated core and without coils. On base of this machine can be realized the DC machine. In the synchronous mode operation, there is no need the sensor of rotor position. It is need only alternative current (AC) voltage source. The advantages of the synchronous machine with DC stator excitation are: the simple brushless design, and controllable field excitation. In this paper, we consider the physical principle operation of a new machine with DC stator excitation in the synchronous mode operation. For analysis in a synchronous mode operation, the simplified model of electrical machine in steady state condition is used.

In the paper, the new method of switching gears is considered in a car transmission box by changing distance between gear axles. The method has the following advantages: high speed switching gears, no needs of the gears synchronization, and easy automation of the process switching. In this case, difference angle speeds of switched gears produces an impact load in teeth of switched gears. Impact loads can be reduced by presence of oil in switched gears. Three stages of the process switching gears are considered when switching by change distance between gears axles. The analysis of the teeth loading is fulfilled for the most important phases of gear switching. As a result, it is concluded about perspective of a reduction of the dynamic loading of gear teeth due to the presence of the lubricating layer in the most loaded contact zone of gears.

Heavy-duty trucks and self-propelled platforms are widely spread for the purpose of transportation of heavy and bulky loads. Power units of these vehicles consist of synchronous electric generators (alternators) driven by diesel engines. The generator supplies electricity to each motor-wheel of the vehicle and to all its systems. Alternators are also used in cars' and trucks' electric systems to supply their electric and electronic devices (e.g., headlights, safety systems, etc.). Substantial reserves of production and quality improvement of such alternators are hidden in their tests technique improvement. In this paper, the software is designed for mobile and stationary test stands of the alternators. The software was created using "LabVIEW" development system. It is designed to be used with "National Instruments®" hardware.

At present time, soot deposit role in the process of transient heat transfer in the diesel engine combustion chamber is studied deficiency. In the paper, a new calculation experimental method of investigation and a new mathematical model are suggested. The new method and model allow evaluating the heat insulation effect of soot deposit. The experimental research of local heat transfer was carried out using a new type of sensors for transient heat flux. Calculated local values of soot deposit show close fit (deviation was about 3 - 9%) to the experimental data. It was specified that soot deposit temperature in normal direction from the heat-loaded surface to the limit depth (detail surface) decreases about 7K per micrometer and heat flux density about 0.5%. Phase delay fluctuations of temperature and heat flux density throughout the soot deposit depth was about Δᵩ = 0.50 of crankshaft angle rotation on each micrometer.

The brushless DC motors with permanent magnets are used primarily in law power applications. There are no limits on weight and motor dimensions in considered motors with DC stator excitation. Brushless series connected machine with DC stator excitation do not have rotor coils. Field coil and armature coils are mounted in the stator. Armature windings are connected to DC voltage source trough power transistors commutator. Power transistors are controlled by reflective optical sensors in function of rotor position. In the report, the new principle design of the motor with DC stator excitation is considered. The new principle of design supposes individual excitation for each of the armature phase. Such approach gives an opportunity to design electrical machine with any number of armature phases spaced in phase from each other. In series connected DC machines, the field winding is connected in series with the armature winding.

As a rule, the work of electric drives of transport mechanisms arises with variable load and with different control laws of torque and speed. That leads to redistribution of losses components and demands take it in attention. In the report, the character change of the general losses and their components are compared in different type of electric drives under change of the load. In connection with this, it is paid attention to features of redistribution of losses in the perspective for transport mechanisms electric drive with field regulated reluctance machine. This machine is characterized by increased reliability, high specific parameters, simplicity of a design and control, and opportunity work in aggressive conditions. The opportunity realization of control laws in the electric drive with reluctance machine (with independent excitation) the same as in the electric drive of direct current machine makes perspective comparison of losses in these electric drives.

One of the basic problems of improving the transport diesel parameters (the fuel economy and decreasing the exhaust gases pollution) is the perfection processes of fuel dispersion and fuel-air mixture creation. The difficulty of estimating the quality of these processes is caused by the complexity of the process in the diesel combustion chamber when the fuel is injected and evaporated. This paper offers a new method of estimating the quality of creating the fuel-air mixture in a high-speed diesel engine. The method is based on the results of non-motor tests. According this method, in a customary stand, used for test the diesel engines fuel-delivery equipment, an extra sensor is added to record the force of hydro-dynamic pressure of a fuel jet on a sensitive surface of the sensor. This sensor is created on the basis of a piezoelectric element, which has high sensitivity and good frequency characteristics (measuring range of frequencies up to 90 kHz).

In the report, a new version of machine with DC stator excitation is discussed. A brushless one phase electrical machine has a very simple design. Rotor has no windings. In generator mode operation, stator has one winding for DC stator excitation and one output winding. In motor mode operation, there is only one sensor of rotor position and one phase H-bridge inverter. One phase machine is symmetrical. Like in dc machines, it is possible to realize here: shunt, series, and separate excitation. In motor mode, the speed control is possible by vary armature (output winding) voltage, varying current excitation, and varying resistance in armature circuit. Simplicity construction and flexibility control opportunities can find for this machine wide application in vehicles. Motor, with series excitation, leads a torque-speed characteristic that is useful for transport power circuit applications. One phase machine is the basic for design of two and three phase machines.

The field regulated reluctance machine is perspective for automotive transport electric drives. In this machine, the switching of a stator current is done in function of a rotor position. The massive salient rotor of the electric machine does not contain windings. The stator is fulfilled in the body and iron of serial ac induction motor. The stator winding sections, which conductors lay above between rotor poles intervals, serve as a excitation winding, and others sections, which conductors lay above rotor poles, the role of a armature winding. In most cases, the optimal winding current waveform is distinct from the sine waveform. For a case of use separate current sources for each phase, the ideal is rectangular waveform. At the rotation of the motor, the each stator section winding pass from a zone of “excitation” to a zone of “armature”. The stator has finite number of phases.

The internal combustion engine gradually concedes the positions of traction unit. The electric drive including the electric motor, electro-generator, and diesel installation, comes on its change. The vector pulse control system of the wound rotor induction motor drive can be one of the perspective variants of such electric drive. The speed control of wound rotor induction motor with thyristor converter, assembled on base of three phase bridge circuit, is considered in report. The entrance circuits of the converter are connected to AC generator through motor stator windings, and converter output circuit (on the side of the dc voltage) connected to a two rotor windings connected in series. The third rotor winding can be connected in parallel or remain free. The stator magneto-motive force is created by switching thyristors. Magneto-motive force is rotating discretely with a step of 60 degrees.

Controller of the high pressure fuel pump position rod drive is the inner loop of the diesel crankshaft rotation frequency control. To make a high fast of the loop of regulating of the diesel crankshaft rotation frequency the inner loop is to be faster. Under such conditions there is a necessity to take into account the discreteness of the work of the voltage converter of the actuator. In the report the questions of design of the fuel pump rod position control are considered on the basis of the method of state-space in the discrete domain. Design includes receiving of the linear difference equations describing of the open loop with the impulse width modulation. The main feature of the description offered in the report is in the direct using the system of the differential equations to get the linear system of the linear difference equations without the step of making up the analytical solution of the differential equations.