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The article solves the problem of reducing electric power losses of the traction induction machine rotor to prevent its overheating in nominal and high-load modes. Electric losses of the rotor power are optimized by the stabilization of the main magnetic flow of the electric machine at a nominal level with the amplitude-frequency control in a wide range of speeds and increased loads. The quasi-independent excitation of the induction machine allows us to increase the rigidity of mechanical characteristics, decrease the rotor slip at nominal loads and overloads and significantly decrease electrical losses in the rotor as compared to other control methods. The article considers the technology of converting the power of individual phases into a single energy flow using a three-phase electric machine equivalent circuit and obtaining an energy model in the form of equations of instantaneous active and reactive power balance.

Overrunning clutches are devices for transmitting rotary motion in one direction only. These mechanisms are widely used in automotive industry, for example, in torque converters, impulse stepless transmissions, inertial continuously variable transmissions, starter engine starting system, and in other similar devices, where torque transmission is performed only in one direction. There are many different designs of the overrunning clutches, for example, ball, roller, cam, ratchet, spring ones, etc. But despite such a variety of designs and great efforts to establish reliable overrunning clutches, these mechanisms are still the weakest parts of many drive systems. Therefore, creation of reliable overrunning clutches is an urgent problem of mechanical engineering. Unfortunately, existing designs of the overrunning clutches have insufficient reliability and durability, which in many cases limits reliability of drive as a whole.

This paper is devoted to development of methodology of system analysis of power distribution systems and development of methods of synthesis of objective laws in the power distribution among drive wheels of a multipurpose wheel vehicle. The methodology of system analysis provides for formulation of the problem; structural analysis of power distribution systems; the synthesis of objective laws in the power distribution; development of methods for their implementation. The methodology is based on the theory of the synthesis of technical systems. In this paper it has been solved the inverse problem of dynamics, namely: in accordance with specified requirements to effectiveness of the multipurpose wheeled vehicle, expressed in the form of formulated performance criteria, it is necessary to determine parameters of characteristics of control actions.

The main indicators for mobility of a multipurpose wheeled vehicle are the maximum and average technical velocity (it is defined as the distance traveled divided by the time elapsed), and they are mainly determined by power-to-weight ratio and the parameters of the suspension. As our analysis shows, with the increase of the power-to-weight ratio of the vehicle and its weight, the growth rate of the velocity is reduced, and after reaching a certain value, the velocity remains almost constant. This is due to the fact that for operating conditions of the multi-purpose wheeled vehicle, movement on roads with different degrees of uneven distribution of the rolling resistance and adhesion, in both transverse and longitudinal directions, is typical.

The main indicators for mobility of a multipurpose wheeled vehicle are the maximum and average technical velocity (it is defined as the distance traveled divided by the time elapsed), and they are mainly determined by power-to-weight ratio and the parameters of the suspension. As our analysis shows, with the increase of the power-toweight ratio of the vehicle and its weight, the growth rate of the velocity is reduced, and after reaching a certain value, the velocity remains almost constant. This is due to the fact that for operating conditions of the multi-purpose wheeled vehicle, movement on roads with different degrees of uneven distribution of the rolling resistance and adhesion, in both transverse and longitudinal directions, is typical.

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.

The inertial continuously variable transmissions are transmissions of mechanical type. They have a number of advantages in comparison with other types of transmissions. For example, they have a big value of the coefficient of efficiency, since the principle of their action does not imply the need to convert energy from one type to another one. These transmissions have a compact design, a wide range of torque transformation. They can operate in direct mode, smoothing the torsional vibrations in the system. At the moment when the output shaft is stopped, the input transmission shaft continues to rotate, that prevents the engine from overloading. There are other advantages. But despite these advantages, the inertial transmissions are not widely used in the automotive industry. The main reason for this is the inadequate durability of the freewheel mechanisms involved in the designs of the inertial transmissions.

The article solves the problem of increasing the energy efficiency of the traction electric drive in the low load conditions. The set objective is achieved by analogy with internal combustion engines by decreasing the consumed energy using the amplitude control of the three-phase voltage of the induction machine. The basis of the amplitude control is laid by the constancy criterion of the overload capacity with respect to the electromagnetic torque, which provides a reliable reserve from a "breakdown" of the induction machine mode in a wide range of speeds and loads. The control system of the traction electric drive contains a reference model of electromechanical energy conversion represented by the generalized equations of the instantaneous balance of the active and reactive power and the mechanical load. The induction machine is controlled by two adaptive variables: the electromagnetic torque and the voltage amplitude.

Dynamics of acceleration, mobility, fuel efficiency of wheeled vehicles are largely determined by the drive circuit to the driving wheels and bridges, as well as devices used in drive link nodes to distribute power among the driving wheels. This is especially important for multi-axle wheeled vehicles. In this paper, the object of the study is a multiaxial wheeled vehicle with an electric transmission consisting of an internal combustion engine with a power of 720 kW, one common generator and twelve traction motors mounted directly on the driving wheels. In connection with the change in load on the driving wheels due to the variability of soil properties, driving conditions (acceleration, braking, uniform motion), terrain topography, it is necessary to provide external regulation of electric machines working in the transmission of the vehicle.

In this paper, we consider the hybrid power train for transportation of long pipes with big diameter. It is includes diesel engine for main towing vehicle and auxiliary electric drive for the active trailer The trains with active trailers are necessary at the building of oil and natural gas pipelines in no road conditions and marshlands. Due to the electric drive, the trailer's off-road capability on marshland conditions is sharply increased and its control is facilitated. The specified attractive qualities are appeared, if wheels of the trailer are executed as drivable, and the kinematic circuit of a drive is fulfilled as one-stage. At this, it is taken in attention that power of the electric drive will take 20 - 25 % from rated power of the basic traction drive, with the expanded range of torque control (till 1:10 and more). Such overloads are provided by the electric drive with synchronous reluctance machine of independent excitation developed by authors.

The main indicators for mobility of a multipurpose wheeled vehicle are the maximum and average technical velocity, and they are mainly determined by power-to-weight ratio and the parameters of the suspension. As our analysis shows, with the increase of the power-to-weight ratio of the vehicle and its weight, the growth rate of the velocity is reduced, and after reaching a certain value, the velocity remains almost constant. This is due to the fact that for operating conditions of the multi-purpose wheeled vehicle, movement on roads with different degrees of uneven distribution of the rolling resistance and adhesion, in both transverse and longitudinal directions, is typical. In this investigation we evaluate the effectiveness of the main methods of power distribution among drive wheels of the multi-purpose wheeled vehicles.

This paper is devoted to development of methodology of system analysis of power distribution systems and methods of synthesis of objective laws in the power distribution among drive wheels of a multipurpose wheel vehicle. The methodology of system analysis provides for formulation of the problem; structural analysis of power distribution systems; the synthesis of objective laws in the power distribution; development of methods for their implementation. The methodology is based on the theory of the synthesis of technical systems. In this paper parameters of characteristics of control actions have been determined in accordance with specified requirements to effectiveness of the multipurpose wheeled vehicle expressed in the form of formulated performance criteria.

Overrunning clutches are devices for transmitting rotary motion in one direction only. These mechanisms are widely used in automotive industry, for example, in torque converters, impulse stepless transmissions, inertial continuously variable transmissions, starter engine starting system, and in other similar devices, where torque transmission is performed only in one direction. There are many different designs of the overrunning clutches, for example, ball, roller, cam, ratchet, spring ones, etc. But despite such a variety of designs and great efforts to establish reliable overrunning clutches, these mechanisms are still the weakest parts of many drive systems. Therefore, creation of reliable overrunning clutches is an urgent problem of mechanical engineering. Unfortunately, existing designs of the overrunning clutches have insufficient reliability and durability, which in many cases limits reliability of drive as a whole.

The main indicators for mobility of a multipurpose wheeled vehicle (MWV) are the maximum and average technical velocity, and they are mainly determined by power-to-weight ratio and parameters of the suspension. As our analysis shows, with the increase of the power-to-weight ratio of the vehicle and its weight, the growth rate of the velocity is reduced, and after reaching a certain value, the velocity remains almost constant. This is due to the fact that for operating conditions of the multipurpose wheeled vehicle, movement on roads with different degrees of uneven distribution of the rolling resistance and tire traction, in both transverse and longitudinal directions, is typical. In this investigation we evaluate the effectiveness of the main methods of power distribution between the drive wheels of the multipurpose wheeled vehicles: disabling of drive axles, blocking of cross-axle and inter-axle differentials, a slowdown of slipping wheels.

Free-wheel mechanisms transmit rotary motion in only one direction. They are widely used, for example, in hydraulic transformers, pulsed continuous transmissions, inertial automatic torque transformers, electrical starters for motors, and metal- and wood-working drives. Unfortunately, existing free-wheel mechanisms are insufficiently reliable and durable and in many cases limit the reliability of the drive as a whole. Thus, the insufficient life of free-wheel mechanisms delays the use of inertial automatic continuous transmissions, which have many benefits over existing transmissions. In most known free-wheel mechanism, the whole torque is transmitted through locking elements such as balls, rollers, eccentric wheels, pawls, slide blocks, and wedges, whose operation at large loads may limit the life of the mechanism.

The problem of the theory of power transmission to wheels of a vehicle, as part of the theory of cars, has always been in the center of attention of specialists. With the improvement of designs of a vehicle there was a need of thorough scientific review of theoretical and experimental aspects of creating and applying of mechanical, hydrostatic, electrical, and combined transmissions. This has always remained one of the most important questions of the rational allocation of power among drive wheels. In the present paper, it has been done study of different methods of power distribution among the drive wheels of an all-wheel-drive truck, namely: method of partial solution; method of introducing a rigid kinematic connection; method of periodical action; and method of limit of excessive action. Assessment how these methods influence on the performance characteristics of a multi-purpose vehicle has been done.

Trucks are one of the most common modes of transport and they are operated in various road conditions. As a rule, all-wheel drive trucks are equipped with special systems and mechanisms to improve their off-road capability and overall efficiency. The usage of blocked mechanisms for power distribution is one of the most popular and effective ways to improve the off-road vehicle performance. However, the lock of differential may adversely affect the stability and control of vehicle because of the unobvious redistribution of reactions acting on wheels, which consequently leads to poor performance and safety properties. Problems of rational distribution of power in transmissions of all-wheel drive vehicles, as well as research in the field of improving directional stability and active safety systems are among the priorities in modern automotive industry.