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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.

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.

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).

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.

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.

The development of Additive Technologies (SLS/SLM, EBM, DMD) suggests the increase of range expansion of materials used. One of the most promising directions is products manufacturing from composite materials. The technology of composite micro-powders production on the basis of heat-resistant nickel alloy EP648 and Al2O3 is proposed. The aim of this research is to develop a method of producing composite micropowders for additive technology application. This method is based on modification of the metal micropowders surface by the second phase in a planetary mixer (mechanochemical synthesis).The obtained composite micropowders are compared with powders which are recommended for selective laser melting usage (produced by MTT Technology). The equipment used in the research: planetary mixer, scanning electron microscopy (SEM), optical granulomorphometer Occio 500nano.

The copper-nickel alloys are widely used in various industries. The adding of nickel significantly enhances mechanical properties, corrosion resistance and thermoelectric properties of copper. The technology was proposed of production of copper-nickel composite micro-powders by the gaseous deposition of nickel on the surface of copper powder. The vaporization of nickel was implemented by using magnetron. The relationship between mode of processing and the ratio of phases in the powder was investigated. The proposed method allows to modify the powder surface without deformation of the particles. The possibility of using of obtained composite powder in selective laser melting (SLM) was evaluated. It is assumed that the structure of the obtained composite material (SLM) will have inclusions of nickel and continuous chain of copper. This structure will have high mechanical properties and high electrical conductivity.

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.

The new wireless rotor electrical machine has all the coils placed on the stator. The laminated wireless rotor serves as a magnetic field switcher. A wireless rotor is cold, and it facilitates machine cooling. The model of the wireless rotor machine includes electrical and mechanical components. The wireless rotor machines can find an application in practice because they have advantages over existing devices. In modeling, we use a new approach. We consider a motor as a natural control system with torque feedback. Such an approach simplifies analyses and adjustment of the operation of an electrical machine. First, we analyze an open-loop control system without torque feedback. In this case, by changing the rotor speed under external torque, we can receive the torque-speed motor characteristics. After some adjustments to the open-loop system, we can consider the close loop control system with torque feedback. We use a space vector representation for sinusoidal electric components.

The treatment of solid surface by powerful streams of charged particles accelerated with power density ≥106 W/cm2 widely used for modification of different materials properties. The fast enter of electron beam power in the material of target causes the flow intense thermal and deformation processes. The changing of the structure, the phase composition, the microrelief of treated surface consequently happens. It is often accompanied by the hardening and increase of the wearing properties. The work proposed of using low-energy high-current electron beam as finish treatment of product obtained by selective laser melting of heat-resistant nickel alloy EP648. The subject of research was the surface properties of the product.

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 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.