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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.

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.

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.

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 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.

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.

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.

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.