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Technical Paper

Modeling of the Automatic Power Distribution System among the Traction Motors of the Driving Wheels of a Multi-Axle Vehicle

2019-04-02
2019-01-0914
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.
Technical Paper

Investigations of Composite Materials for Their Applications in Designs of Vehicles

2019-04-02
2019-01-1120
At present, there is a tendency to replace metals with nonmetals, including composite materials. More and more works are devoted to the creation and investigation of the structure and properties of nonmetallic materials. Composites, being a heterogeneous anisotropic or quasi-isotropic system, combining the positive properties of components and possessing a complex of new properties not inherent in any of them, allow to substantially improve the basic characteristics of materials. The main requirement applied to parts of vehicles made of polymer composite materials is the ability to withstand a high operating temperature and pressure. Modern polymer composite materials consist of reinforcing fillers and a polymer matrix. Reinforcing fillers can be made of: fiberglass, organic fiber, carbon fiber and are able to withstand the required operating temperature and pressure with ease.
Technical Paper

Energy-Efficient Traction Induction Machine Control

2019-04-02
2019-01-0598
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.
Journal Article

Basic Characteristics of Adaptive Suspensions of Vehicles with New Principle of Operation

2017-03-28
2017-01-0404
Currently, a group of scientists consisting of six doctors of technical sciences, professors of South Ural State University (Chelyabinsk, Russia) has completed a cycle of scientific research for creation of adaptive suspensions of vehicles. We have developed design solutions of the suspensions. These solutions allow us to adjust the performance of the suspensions directly during movement of a vehicle, depending on road conditions - either in automatic mode or in manual mode. We have developed, researched, designed, manufactured, and tested experimentally the following main components of the adaptive suspensions of vehicles: 1) blocked adaptive dampers and 2) elastic elements with nonlinear characteristic and with improved performance.
Technical Paper

Evaluation of Stability and Control of Movement of 6x6 Truck for Different Operating Modes

2017-03-28
2017-01-1575
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.
Technical Paper

Adaptive Suspension of Vehicles with Wide Range of Control

2016-09-27
2016-01-8032
In this paper we consider a new design of adaptive suspension systems of vehicles with better technical characteristics and functional abilities in comparison with existing designs. We have developed the following main suspension components of vehicles: a lockable adaptive shock absorber with a wide range of control performance, implementing "lockout" mode by means of blocking adaptive shock absorber, and an elastic element with progressive non-linear characteristic and automatic optimization of localization of work areas. Advantages of our developments in the vehicle suspensions are the following: 1) when the vehicle is in a wide range of speeds in a so-called "comfort zone", we have managed, by applying the non-linear elastic element, to reduce significantly the stiffness of the elastic suspension elements in compare with the regular structures - at least in two times. This means that comfort, smooth motion, high performance the vehicle when driving over bumps are improved in times.
Technical Paper

Investigations of Power Distribution in Transmissions of Heavy Trucks

2016-04-05
2016-01-1100
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.
Technical Paper

Power Distribution in Transmissions of Multi-Wheeled Vehicles

2016-04-05
2016-01-1103
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.
Technical Paper

Efficient Power Distribution in an All-Wheel Ground Vehicles

2016-04-05
2016-01-1105
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.
Technical Paper

Method of Calculating of Relay Type Free-Wheel Mechanism

2015-09-29
2015-01-2782
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.
Technical Paper

Methodology of System Analysis of Power Distribution among Drive Wheels of an All-wheel-drive Truck

2015-09-29
2015-01-2788
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.
Technical Paper

Rational Criteria for Power Distribution in All-wheel-drive Trucks

2015-09-29
2015-01-2786
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.
Technical Paper

Effectiveness of Methods of Power Distribution in Transmissions of All-Wheel-Drive Trucks

2015-09-29
2015-01-2732
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.
Technical Paper

Comparative Analysis of Methods of Power Distribution in Mechanical Transmissions and Evaluation of their Effectiveness

2015-04-14
2015-01-1097
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.
Technical Paper

An Adaptive Suspension of Vehicles with New Principle of Action

2014-09-30
2014-01-2310
We have developed a fundamentally new design of adaptive suspension systems of vehicles. Their technical characteristics and functional abilities are far better than the existing designs of suspensions. We have developed the following main suspension components of vehicles: a lockable adaptive shock absorber with an ultra-wide range of control performance, implementing “lockout” mode by means of blocking adaptive shock absorber, and an elastic element with progressive non-linear characteristic and automatic optimization of localization of work areas. Our patents confirm the novelty and efficiency of our major design decisions. Advantages of our developments in the vehicle suspensions are the following.
Technical Paper

Electric Drive of an Industrial Tractor

2013-09-24
2013-01-2469
A traction electric drive is offered for an industrial tractor. The drive contains the generator, the controlled rectifier, the independent inverters, and two onboard motors. The important feature of the offered electric drive is application of synchronous reactive machines of independent excitation as the generator and traction motors. These electric machines have the following technical features: the generator and motor design is brushless; and simple, the rotor has high mechanical rigidity that raises reliability at high speeds and overloads. There are no windings on the rotor; the motor is designed for ease of manufacture (by expert estimations its price is lower than the squirrel cage induction motor on the order of 15-20 %). The machines have increased efficiency a result of a “cold” rotor design; the motors have high torque overloads capacity (up to 4-6 times the values of nominal torque).
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