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The article describes a project to create an electric transmission for ground vehicles. As a layout, a motor-wheel variant is proposed, in which a traction electric motor, power electronics, control system and brake system are integrated into the wheel disk. This arrangement of the traction motor allows you to free up the space of the car for comfort and placement of the electric power storage. A combined excitation machine is proposed as an electric motor, the magnetic flux in which is created simultaneously by permanent magnets and an excitation winding. Permanent magnets allow you to increase the power in the limited dimensions of the disk, and the excitation winding allows you to adjust the magnetic flux, which significantly expands the range of speeds and torques of the vehicle. The design of the electric motor is innovative and protected by a patent of the Russian Federation. To develop a number of similar motor wheels, a design system has been proposed, which consists of two parts: synthesis and analysis. The synthesis system generates the optimal geometry of the electric motor for a specific technical task of the customer. It contains a multi-level structure that allows you to implement developments for various project situations with and without restrictions. The system contains seven such levels. Optimality criteria can be selected depending on the requirements of the project. The analysis system is based on the principle of a digital double. Its methodological basis is the finite element method. The system allows you to conduct a detailed analysis of the electromagnetic and thermal state, to obtain all the necessary integral characteristics. The performance of the design system has been tested on a digital analogue of a real racetrack, which is divided into sections with specified speed modes. The program outputs 15 parameters of both the car and the electric motor. In conclusion, the article shows the design study of a motor wheel for a racing electric car. The design of the prototype and the results of its tests are presented. The design system for the development of motor wheels based on a valve motor of combined excitation can be used for mass production.

Creation of comfortable housing for the population meeting the modern requirements of ecology, aesthetics, economical energy consumption and healthy lifestyle is a strategic task of any state. The world’s leading countries have achieved significant results in this direction. In the context of economic sanctions, Russia will not be able to take advantage of the scientific achievements of foreign countries. In addition, our country has its own climatic features. Therefore, this strategic direction of development should be implemented independently. The project should go through several stages of development. At the first stage, all the necessary scientific research should be carried out. In the second stage, these scientific studies should find their engineering solutions. At the third stage, an industry for the production of such settlements should be established. This article attempts to formulate the basic requirements for the house, site and the most ecological settlement. The authors of the project consider this to be a very important initial stage of the project development.

The development of modern energy is moving towards distributed generation, in which numerous sources of different capacities are connected into a single network. This makes it possible to increase the reliability of the entire system, since the probability of the failure of several energy sources at the same time is small. One of the major possibilities of distributed generation is the generation of electric energy based on high-speed gas turbines. The main advantage of these sources are high specific energy indicators, which improve with increasing rotation speed. However, it is technically difficult to realize the advantages of high-speed devices. It is necessary to abandon the step-down gearbox for the generator and directly connect it to a high-speed turbine, use high-strength materials that can withstand the load from centrifugal forces, abandon traditional plain bearings, and use special supports. Installations with generators that have a radial rotor design are the most widespread. The main problem with generators of this type is that the rotor diameter is limited by the mechanical strength from centrifugal forces and the power can be increased only by increasing the axial length. At the same time, only two supports can be used for a radial structure; this leads to a decrease in the rigidity of the shaft and the occurrence of resonant frequencies during acceleration. In addition, radial generators have unreasonably large losses in the stator magnetic circuit, which increase with increasing speed and are difficult to remove from a limited volume. For this reason, radial structures have exhausted their reserves and cannot develop further in the direction of increasing the speed of rotation. This article proposes the design of a high-speed gas turbine installation based on a generator of a fundamentally different design. This is a multi-section generator with an axial air gap. The electric machine has a diamagnetic armature, which eliminates magnetic losses and allows for increased efficiency and simplification of the design. A large number of rotor sections can be used as supports for a gas-dynamic bearing, which greatly increases the rigidity of the structure and eliminates resonant frequencies during acceleration. The main structural difference from existing designs is the use of two types of bearings at the same time: magnetic bearings and gas-dynamic bearings. Magnetic bearings ensure operation at low speeds during acceleration, and gas-dynamic bearings ensure the rotation of the rotor and its rigidity at high speeds. Analysis of developments in this area shows that this solution is innovative. The proposed design required study of both the power part, including the axial inductor and the diamagnetic armature, and the combined support. This article shows the results of the development of a combined suspension and provides calculations of magnetic and gas-dynamic bearings for a gas turbine installation of 100 kW and 70,000 rpm. The results of the study can be applied to a number of gas turbine installations from 10 kW to 500 kW. The authors consider this concept to be competitive with modern analogues that have a radial generator design. [ABSTRACT FROM AUTHOR]

Various strategies are proposed to date in order to convert CO2 to large diversity of useful chemicals. The following review discusses two important approaches that produce methanol from CO2. These two includes CO2 hydrogenation and electrocatalytic routes. These processes could recycle CO2, permitting a carbon neutral, closed loop of fuel combustion and CO2 reduction to prevent a rising concentration of this greenhouse gas in the atmosphere. Besides, intermittent electricity generation can be stored in an energy-dense, portable form in chemical bonds. The present review reports more recent findings and drawbacks of these two processes. The present review study revealed that the hydrogenation process could become readily operational in comparison to electrocatalytic process. The electrocatalytic approach still has serious technical issues in terms of kinetically sluggish multi-electron transfer process during CO2 reduction reaction that requires excessive over-potential, relatively poor selectivity, poor durability in the long term, and the absence of the optimized standard experimental and commercial systems. [ABSTRACT FROM AUTHOR]

The article presents the method of synthesis and analysis of the brushless motor with claw-poles. The motor is designed for the pilger mill drive for manufacturing seamless tubes. The peculiarity of the drive is that electric machines of this class for high power have not yet been used in world practice. In this regard, a very thorough analysis of the designed motor is required to remove technical risks in the manufacture of prototypes. For design of this motor the synthesis system and the analysis system were developed. The synthesis system is developed on the basis of nonlinear programming methods. For the analysis, it is proposed to use the program Ansys Electronics Desktop, which implements the finite element method. The peculiarity of using this program is the need to use large computer resources. Herewith, the calculation time of the main characteristics is often not acceptable for practical calculations and takes several hours. The authors propose a simplification of the computational model without significantly reducing the accuracy of the calculation. The brushless motor with claw-poles is replaced by a brushless motor with tangential magnets. The stator designs and the magnetic fluxes of the motors are the same. The effectiveness of such a replacement is shown in the real project. Calculation time with acceptable quality is reduced to a few minutes. This approach is recommended for the creation of design systems of other types of brushless machines. This scientific research was carried out for a real customer. [ABSTRACT FROM AUTHOR]