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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.

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.

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 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.

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.

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.

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.

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.

The development of the economy and the associated growth in trade both within the country and international transport, the associated construction and development of transport routes using elements of intelligent transport systems constantly require increasing the efficiency of trunk transportation. In addition, the development of new economic regions with an undeveloped road network is impossible without high-capacity motor vehicles and cross-country ability. To achieve these goals, the creation of active road trains, including multi-link ones, based on non-traditional technical solutions, is required. The idea of using multi-link trains in the system of intercity and international transportation is not new. However, at the present stage of development of automotive technology requires rethinking and use of new achievements of science and technology.