Open Access
Access granted
Subscription or Fee Access
Vol 18, No 1 (2024)
- Year: 2024
- Articles: 8
- URL: https://journals.eco-vector.com/2074-0530/issue/view/8044
- DOI: https://doi.org/10.17816/2074-0530-2024.18.1
Combined power plants
Features of development of the mathematical model of the electric motorcycle thermal regulation system
Abstract
BACKGROUND: Use of thermal regulation systems is necessary to maintain the required temperature range of electrical components of electric vehicle. Even at the design stage of the vehicle, the being developed mathematical model of the thermal regulation system helps to determine the necessary parameters of the thermal regulation system, to select algorithms for controlling the system and to calibrate the developed algorithm to ensure the necessary heat removal from electrical components.
AIM: Development of a mathematical model of the thermal regulation system of an electric motorcycle, aimed at determining the potential capabilities of optimizing the system by controlling the air flow through the radiator.
METHODS: The mathematical model is built in the AVL Cruise software environment. The properties of the components included in the model were obtained as a result of laboratory studies and supplemented with the equilibrium equations of power at the inputs and outputs taking into account their efficiency.
RESULTS: Using the developed model of the radiator of the thermal regulation system, the temperature graphs of the electric motor and the inverter of the electric motorcycle during the driving cycle were obtained. It is noted that the applied thermal regulation system is capable of maintaining the temperature of electric components in the specified range.
CONCLUSIONS: The mathematical model of the radiator of the thermal regulation system proposed in this paper makes it possible to carry out calculations of the system at the stage of design of electric vehicles. In addition, the model has a potential for further development aimed to fuller determination of the parameters of the thermal regulation system, including the thermal efficiency.
5-12
The electromechanical device for energy accumulation
Abstract
BACKGROUND: Short-term peak loads of machines and mechanisms arise necessity in mechanical energy accumulation for its consequential impulse use. For instance, it is quite relevant for trucks at the initial stage of dragging heavy trailers. Use of mechanical energy accumulator will help to decrease truck engine power and to enlarge its functional capabilities.
AIM: Development of the mathematical model of the mechanical energy accumulator.
METHODS: The mechanical energy accumulator can be made either as a permanent magnet synchronous machine or as a converter-fed electric motor with the super flywheel mounted at the motor shaft. When the machine is connected to the supply source, the non-stationary process described with two differential equations, mechanical and electric, occurs. Solutions of the differential equations replicate ratios for charging and discharging of an electric capacitor.
RESULTS: According to the obtained formulae, the mechanical energy accumulator seems identical to an electric capacitor for an electric circuit. Therefore, artificial electric capacity can be discussed. Moreover, artificial electric resistance not related to conductor’s specific resistance, length and cross-area, occurs. In view of the aforesaid, the mechanical energy accumulator can be considered as an artificial electric capacitor accumulating not electric field energy but kinematic energy of super-flywheel’s rotation.
CONCLUSIONS: There are designs of super-flywheels capable of accumulating sufficient amount of kinetic energy. The ability of implementing them into passenger vehicles was studied as well. In this context, massive trucks have an undeniable advantage because weight increase is not only non-problematic but preferable in some cases.
13-18
Transport and transport-technological complexes
Study of efficiency of the algorithm of acceleration and deceleration control of a wheeled vehicle by means of the accelerator pedal
Abstract
BACKGROUND: As fuel costs are among the significant ones in vehicle operation, it is promising to use vehicle with electric drivetrains, such as battery electric vehicles, which make it possible to reduce these costs. The main key feature of them is mileage at one charge. In order to maximize this feature, designers are working on implementing more advanced energy sources with higher capacity and reducing energy transfer losses from the energy source to the driving wheels. In this path, electric drive is the main source of energy loss. Therefore, it is important not only to use more advanced electric drivetrains, but also to improve control algorithms. For the sake of this, it is necessary to define set points of demanded torque from the engine using only the accelerator pedal taking into account motion velocity, other conditions and vehicle performance. Implementation of this law helps driver to reduce energy consumption, as the vehicle is capable of moving using its inertia (free running) and using regenerative braking at maximum with minimal activity of main braking system.
AIM: Study of operation and efficiency of the algorithm of definition of traction and regenerative torque set points for the traction electric drive, definition of the free running mode depending on motion velocity and definition of the accelerator pedal position using methods of mathematical modeling of vehicle dynamics.
METHODS: The study of operation and efficiency of the law of definition of traction and regenerative torque set points for the traction electric drive and definition of the free running mode was conducted in the MATLAB/Simulink software package.
RESULTS: The paper contains fundamentals of building the algorithm of definition of traction and regenerative torque set points for the traction electric drive and definition of the free running mode, results of virtual study of operation and efficiency of this algorithm for driving a vehicle in the MATLAB/Simulink with virtual conditions relevant to the real ones.
CONCLUSIONS: The practical value of the study lies in ability of using the proposed law of definition of traction and regenerative torque set points for the traction electric drive and definition of the free running mode for development of control systems for traction drive of transport vehicles in order to increase their energy efficiency.
19-32
Mobile additional armor protection for a truck
Abstract
BACKGROUND: The use of armored vehicles helps to protect special vehicles and special equipment from the effects of light and heavy small arms, landmines, and hand grenade launchers during marches or special operations under the threat of constant enemy influence. However, at present, the issue of protecting freight transport used for transporting personnel, mortar crews, materiel, etc. is quite acute.
AIM: Development a mobile set of additional armor protection for the truck body (using the Ural 4320, the KamAZ-4310 and their modifications as the example) in order to reduce the likelihood of injury to personnel during their transportation by firearms, cumulative ammunition, fragments of artillery ammunition, as well as military equipment during its transportation.
METHODS: Determining the parameters for the duration of the penetration process and the subsequent behavior of the armor protection, obtaining accurate data on the resistance and effectiveness of additional armor, and analyzing the stress-strain state were performed in the Ansys software. The data on the penetration process, transition energy and subsequent behavior of armor protection, which will be used to improve armored structures and frameworks, as well as to improve the safety of equipment in real combat conditions, was obtained.
RESULTS: The article discusses the problem of armor protection of vehicles. Examples of the use of additional armor protection for weapons, military and special equipment, in particular in the context of a special military operation, are given. The mobile set of additional armor protection for the truck body, designed to protect personnel from injury caused by firearms and fragments from exploding ammunition when transported by trucks, is presented in the study. Armor protection is made as two hinged armor plates with the size of 1200x2000 mm and two anti-cumulative grilles with the size of 1200x2000 mm, mounted on the outside with fastening elements. Hinged armor screens are straight or bent sheets of armor steel with structurally specified dimensions and places for fastening. Installed on the outside of the body, they act as a barrier, which significantly increases the protective properties when fired from a firearm. The proposed protection set was simulated and the stress-strain state was analyzed in the article.
CONCLUSIONS: Based on the simulations, the values of the maximum velocity and flight range of a bullet were determined for the strength of the additional set of armor protection.
33-42
Electrotechnical complexes and systems
Development of a controller for the position sensor based on a sine-cosine rotary transformer
Abstract
BACKGROUND: Sine-cosine rotary transformers, being electromechanical position sensors, have a relatively high accuracy and resistance to harsh operating conditions, which makes them attractive for use in automotive machinery and equipment installed on its base. Special controllers with software and hardware implementation are designed to generate excitation voltages, to process measuring signals and to calculate, depending on them, the angular position of the shaft where the sensor is installed.
AIM: Development of software and hardware for a controller of the position sensor based on a sine-cosine rotary transformer in the amplitude mode.
METHODS: Taking into account electromagnetic processes, which are the basis of the operation of a sine-cosine rotary transformer in the amplitude mode, system analysis methods, methods of software developing and debugging, methods of experimental researches and processing their results were applied.
RESULTS: A detailed description of the controller of a sine-cosine rotary transformer in the amplitude mode as well as its implementation using microprocessor technology and specialized tools for generating, capturing and processing signals are given. The structure of the controller software is given, as well as technical solutions aimed at improving the accuracy of measuring the angular position and the reasonable implementation of computational processes are described. The results of the experimental study illustrate the achievement of the given aim.
CONCLUSIONS: The development of a controller for a sine-cosine rotary transformer in the amplitude mode required the detailed consideration and coordination of electromagnetic, electrical and computational processes, as well as the use of various technical solutions aimed at improving the accuracy of measuring the angular position. The results obtained can be applied in the development of controllers for various electromechanical position sensors.
43-52
On the issue of contactless alternators on movable objects
Abstract
BACKGROUND: This article discusses automotive inductor alternators of domestic and foreign production with different power and design. A comparative analysis of inductor alternators according to the main electromagnetic parameters and design is carried out. Based on the results of the comparative analysis, conclusions are drawn about the competitiveness of domestic inductor alternators and their superiority over foreign analogues.
AIM: Research and comparative analysis of tractor inductor alternators in order to determine the optimal design, as well as the main characteristics and parameters.
METHODS: The calculation of the magnetic circuit and the idling characteristic is based on the method of successive approximations using iterations. A well-known method with the Blondel diagram is used to calculate the current-speed curve.
RESULTS: A review and comparative analysis of automotive inductor alternators of domestic and foreign production, with various magnetic systems and design, is carried out. The advantages and disadvantages of the magnetic circuit of inductor alternators of both domestic and foreign production are determined and given in comparative tables and current-speed curves. The optimal design of the inductor alternator with the most effective technical and economic indicators was chosen to perform the calculation.
CONCLUSIONS: The calculation of the magnetic circuit and idling characteristics of the 11.3701 three-phase single-pole, single-pack inductor generator with a classical toothed zone and a two-half-period rectifier is carried out. The calculation of the current-velocity curve was performed using the well-known method with the Blondel diagram and the method of successive approximations using iterations.
53-62
Analysis of computer-aided manufacturing systems
Abstract
BACKGROUND: Process of design and development of a controlling program starts after the conclusion of the previous stage of the product life cycle and it begins with the work of an engineering center. At this stage, development of new design solutions takes place and technical requirements specification for the developed product is approved with the customer.
AIM: Process of design and development of a controlling program starting after the conclusion of the previous stage of the product life cycle and beginning with the work of an engineering center.
METHODS: Based on that, the drawing of the product including technical requirements is prepared. Then, generally, this drawing is handed over to the department of process engineers-programmers where the design and development of the process control for the product takes place. As a rule of thumb, at this stage, a process engineer seeks advice from a drawing developer to obtain a full information about the product in order to eliminate any mistakes. There are possible cases where at this moment the drawing is given back to the engineering department due to impossibility of product manufacturing caused by lack of manufacturing abilities or poor design solutions making describing of manufacturing technology impossible.
RESULTS: The study result is the fact that the next stage that follows obtaining the technical requirements specification is development of technological process. The technological process should be formulated properly in terms of technology in accordance with internal enterprise standards (each enterprise can have own standards but the formulation structure is unite) and be sufficiently informative for the sake of exclusion of high chances of rejects during manufacturing. As the statistics shows, many enterprises suffer from high reject rate caused by improper behavior of CNC operators because of disappointments to the technological process.
CONCLUSIONS: Based on results of metalworking simulation, the method aimed to optimization of the strategy of machining high-speed metalworking at development of a controlling program has been formulated.
63-74
Heat engines
The monoreactive multibody floating-frequency oscillator
Abstract
BACKGROUND: The study is related to the machine science field and to oscillating mechanical systems in particular. The study relevance is explained with the fact that oscillations of inertial masses can be found all-around.
AIM: Development of the mathematical model of the monoreactive multibody floating-frequency oscillator.
METHODS: It is proved that points x1, x2, …., xn, which are coordinates of the end of the random vector R in the coordinate system 0xz1, 0xz2, …., 0xzn, are vertexes of a regular polygon. Shape and size of the polygon are not related to coordinates of the vector R, so they are constant. The center of the regular polygon always coincides with the middle of the vector R. In the considered (idealized) case, the polygon with the oscillating bodies with the mass m located at vertexes belongs to the plane Z. In technical applications, bodies should not impede motion of each other, so each body should have an own plane, and all planes should be in parallel (alike the multipiston mechanism).
RESULTS: The condition of occurrence of natural harmonic oscillations is equal-zero full energy of the system, which is exclusively kinematic in the considered case and which ensures monoreactive behavior of the oscillator. In the considered multidimensional planar monoreactive oscillator, free harmonic oscillations of bodies can occur.
CONCLUSIONS: Only kinetic energy takes part in energy exchange. There is no necessity in spring elements. The oscillator does not have fixed value of natural oscillation frequency. The frequency depends on initial velocities and location of bodies. The regular polygon x1, x2, …., xn executes double rotation: around the point 0 and around the point r. Meanwhile, bodies execute linear harmonic oscillations with the amplitude of R. Use of either a slider-crank mechanism or a rod-crank mechanism helps to make bodies move in parallel. The obtained results can be used in development and study of mechanisms executing reciprocating motion in piston engines, in mechatronics and robotic systems, in hydraulic machines, vacuum and compressor machinery, in hydraulic and pneumatic systems, in on-ground transport and technological means and facilities.
75-81