Vehicle Transmission Research Articles

New-Energy Vehicle Transmission System Optimization and Design

New-Energy Vehicle Transmission System Optimization and Design

Energy management for regional microgrids considering energy transmission of electric vehicles between microgrids

As the proliferation of electric vehicles (EVs) continues to accelerate, the inherent attributes of EVs warrant meticulous consideration in the realm of energy dispatch. In order to evaluate the ability of EVs as mobile energy storage, this paper presents an energy management framework for the microgrids' online dispatch, which accounts for the spatio-temporal energy transmission of EVs between microgrids. The energy management framework contains two iterative processes: optimizing charging price and guiding charging dispatch. To sufficiently capture the uncertainties of the renewable energy and load demand, chance-constrained optimization is utilized to determine the charging price by reasonable power allocation. To achieve a continuous and efficient control policy, a normalized advantage function-deep Q learning network (NAF-DQN) is developed for EV dispatch under V2G technology. The above two processes as a coupled optimization problem are solved alternately until convergence. Numerical cases considering energy transmission of EVs between microgrids are studied to demonstrate the superiority of the proposed dispatch framework. The simulation results indicate improved computational efficiency and higher-quality solution.

Nonlinear Vibration Analysis of the Coupled Gear-Rotor-Bearing Transmission System for a New Energy Vehicle

Considering the effects of time-varying meshing stiffness, time-varying support stiffness, transmission errors, tooth side clearance and bearing clearance, a nonlinear dynamics model of the coupled gear-rotor-bearing transmission system of a new energy vehicle is constructed. Firstly, the fourth-order Runge–Kutta integral method is used to solve the differential equations of the system dynamics, and the time-varying meshing force diagram, time history diagram, phase diagram, FFT spectrum diagram, Poincaré map and bifurcation diagram of the system are obtained to study the influence of the external load excitation frequency on the dynamics characteristics of the system. In addition, the multiscale method is used to analyze the main resonance characteristics of the system and to determine the main resonance stability conditions of the system. The effect of time lag control parameters and external load excitation frequency on the main resonance of the system is analyzed by numerical methods. The results show that the gear-rotor-bearing coupled transmission system of the new energy vehicle has obviously nonlinear characteristics, avoiding the system instability interval reasonable selection of external load excitation frequency, meshing damping, time lag parameters and load fluctuations, which can be used to improve the stability of the transmission system of the new energy vehicle.

The drag characteristics prediction of multi-plate frictional wet clutches in vehicle transmissions

The drag characteristics prediction of multi-plate frictional wet clutches in vehicle transmissions

Dynamic axial and radial temperature prediction of multi-plate frictional wet clutches in vehicle transmissions with the thermal resistance network method

Dynamic axial and radial temperature prediction of multi-plate frictional wet clutches in vehicle transmissions with the thermal resistance network method

Optimizing Gear Shifts in an Automatic Transmission for Light Commercial Vehicles

Optimizing Gear Shifts in an Automatic Transmission for Light Commercial Vehicles

Energy Consumption Optimization Strategy of Hybrid Vehicle Based on NSGA-II Genetic Algorithm

Hybrid electric vehicles (HEVs) have certain advantages over internal combustion engines in terms of energy consumption and emission performance. However, the transmission system parameters are uncertain. The low matching between the engine and the power transmission system makes it a big problem to improve the efficiency of hybrid vehicles. Therefore, the multi-objective optimization design of hybrid vehicles is studied. The transmission system parameters of hybrid vehicles are analyzed from the objective function, decision variables, and constraints. The NSGA-II algorithm with elite strategy is introduced to realize the optimal selection of parameters and formulation of energy consumption optimization strategy. The results showed that the multi-objective optimization algorithm could adjust the position of the working point of the engine and improve the efficiency by more than 10%. There was an average difference of 2.15% after the improvement in the fuel consumption of four-gear vehicles. The fuel consumption per 100 km decreases by more than 3%. The maximum climbing gradient of the whole vehicle was 33.9%. The power factor of the direct gear of the maximum power factor increases by 15% after the improvement. The multi-objective energy consumption optimization design of hybrid vehicles proposed in the study can effectively improve the economic and dynamic performance of the whole vehicle and reduce fuel consumption. It provides a reference for the optimization of the hybrid vehicle transmission system.

A Support Vector Machine-Based Approach for Bolt Loosening Monitoring in Industrial Customized Vehicles.

Machine learning techniques have progressively emerged as important and reliable tools that, when combined with machine condition monitoring, can diagnose faults with even superior performance than other condition-based monitoring approaches. Furthermore, statistical or model-based approaches are often not applicable in industrial environments with a high degree of customization of equipment and machines. Structures such as bolted joints are a key part of the industry; therefore, monitoring their health is critical to maintaining structural integrity. Despite this, there has been little research on the detection of bolt loosening in rotating joints. In this study, vibration-based detection of bolt loosening in a rotating joint of a custom sewer cleaning vehicle transmission was performed using support vector machines (SVM). Different failures were analyzed for various vehicle operating conditions. Several classifiers were trained to evaluate the influence of the number and location of accelerometers used and to determine the best approach between specific models for each operating condition or a single model for all cases. The results showed that using a single SVM model with data from four accelerometers mounted both upstream and downstream of the bolted joint resulted in more reliable fault detection, with an overall accuracy of 92.4%.

A UAV-assisted V2X network architecture with separated data transmission and network control

With the explosive increasing number of connecting devices such as smart phones, vehicles, drones, and satellites in the wireless networks, how to manage and control such a huge number of networking nodes has become a great challenge. In this paper, we combine the advantages of centralized networks and distributed networks approaches for vehicular networks with the aid of Unmanned Aerial Vehicle (UAV), and propose a Center-controlled Multi-hop Wireless (CMW) networking scheme consisting of data transmission plane performed by vehicles and the network control plane implemented by the UAV. Besides, we jointly explore the advantages of Medium Access Control (MAC) protocols in the link layer and routing schemes in the network layer to facilitate the multi-hop data transmission for the ground vehicles. Particularly, the network control plane in the UAV can manage the whole network effectively via fully exploiting the acquired network topology information and traffic requests from each vehicle, and implements various kinds of control based on different traffic demands, which can enhance the networking flexibility and scalability significantly in vehicular networks. Simulation results validate the advantages of the proposed scheme compared with existing methods.

Key Technologies of Collaborative Target Detection between Self-propelled Anti-aircraft Weapons

In the case of a lack of target information, a self-propelled anti-aircraft weapon can complete its own combat functions by using the detection information of other vehicles through detection coordination technology. When using the detection coordination technology to process the detection information of other vehicles into information that can be used by the vehicle, the relative position and attitude of the vehicle and data transmission delay will affect the accuracy of the processed target information. With the system of detection collaborative technology expounded, emphasis is attached to the research on the detection coordination method based on pure angles without considering distance. A mathematical model of detection coordination technology is created, the approximate statistical law of the processed detection coordination information is obtained through the Monte Carlo method, and the influence of various factors on transmission error analyzed. In addition, the polynomial curve fitting method is used for time alignment, and the unscented Kalman filter method based on singular value decomposition adopted to reduce the information transfer error. The simulation results show the the method is effective for that end.

Wireless Charging Control for Electric Vehicles

Abstract: Wireless power transmission is a way to transmit power without a wire. Wireless power transmission helps connect areas where people do not have access to an adequate power source. Anyone can get clean and green wireless power. From now on, all devices will be connected to the power source wirelessly. Wireless charging for electric vehicles has been in development for several years before the widespread use of these vehicles. Today, wireless charging systems offer an efficient and flexible way to charge electric vehicles of several categories and different capacities from a common base source. Standardization work is well underway to ensure system compatibility between vehicles and locations. In this paper, we presented successful experimental experiments for wireless power transmission and the future scope of wireless power transmission in electric vehicles

The technical assessment of the level of innovative traction transmission of railway vehicle

The article deals with the development of an innovative model of traction transmissions of railway vehicles with a higher technical level, which allows to eliminate the existing shortcomings of the mechanical system, simplify the repair processes and reduce the cost, and evaluate its technical level. By reducing the overall dimensions and weight of the mechanical system, increasing reliability due to equal distribution of the load and shortening the power arm, as well as reducing the number of structural elements, increasing the useful work coefficient due to the reduction of the mass of double sliding pads and rotating parts, saving electricity and thereby improving the technical level of rail transport. Traction transmissions consisting of an innovative reducer are offered that ensure the increase.
 The technical level of the proposed dart transmission is determined based on three compatibility parameters with a creative approach. Compatibility parameters are determined according to the minimum value of the geometric dimensions characterizing the mass of the mechanical system, the maximum value of the useful work coefficient characterizing economic efficiency, as well as the maximum values of the degree of reliability characterizing safety. The technical level of the proposed project transmitter is determined and compared with existing buildings, its technical and economic advantages are highlighted. As a result of the application of the proposed innovative reducers in the traction drives of railway vehicles, the basis is created for reducing the cost and maintenance costs of traction vehicles, increasing the level of traffic safety, as well as improving the traction and braking characteristics

Parameter Optimization and Control Strategy of Hybrid Electric Vehicle Transmission System based on Improved GA Algorithm

Most of the traditional hybrid electric vehicles (HEVs) choose to optimize the transmission ratio parameters, and the parameter changes of the whole vehicle and other components are only calculated as fixed values. It is difficult to give consideration to the optimization of the economy and power of hybrid vehicles. Therefore, the research proposes to build the transmission ratio, the required power of the vehicle’s working mode, and other models through the dynamic analysis. The parameters of the whole vehicle are optimized on the basis of parameter matching. At the same time, this paper chooses to adopt a hybrid optimization algorithm, combining particle swarm optimization (PSO) and genetic algorithm (GA). The weighted average method and constraint method are used to design the fitness function. The simulation experiment is carried out by Cruise software and MATLAB. Compare the iterative fitness of the PSO-GA algorithm with the traditional PSO and GA algorithm. It can be concluded that PSO-GA converges at the 12th iteration, with an average optimal fitness of 0.5239, which is higher than the traditional algorithm. At the same time, the parameter optimization of PSO-GA and the simulated annealing algorithm is compared. It is found that in the same task, the gasoline consumption after SA algorithm optimization is 0.561 L, while the fuel consumption under PSO-GA algorithm optimization is 0.475 L. The method proposed in this study has improved the power and economy of the HEV model and is effective.

Optimization of multi-speed transmission for electric vehicles based on electrical and mechanical efficiency analysis

Multi-speed transmissions for electric vehicles (EVs) can better improve EV efficiency and performance in comparison with conventional single-speed transmissions. To achieve a superior multi-speed transmission design, gear ratios and shifting patterns should be optimized by considering the electrical and mechanical efficiencies. Because most powertrain losses occur in the inverter, motor, and transmission, loss analysis was conducted according to the characteristics of each component. To confirm the effects of these component efficiencies on EVs, an EV efficiency analysis was performed based on three cases of powertrain efficiency by considering the variable efficiency of each component combination: i) motor only, ii) motor and transmission, and iii) inverter, motor, and transmission. An optimization problem was formulated by adopting design variables, such as gear ratios and shifting patterns, and the objectives of energy consumption and acceleration ability. An artificial neural network (ANN)-based multi-objective optimization process was proposed as an alternative to the excessive effort for calculation in the optimization process. To verify the importance of considering the efficiency of various powertrain components, transmission optimization was performed for the variable efficiency of each component combination. When comparing the highest efficiency solutions of the cases considering only part of component efficiency with the case considering all components, the energy consumption and acceleration ability of the latter case were found to be superior by approximately 1.7% and 5.1%, respectively. Furthermore, since the computational time for the EV and ANN models required approximately nine months and one day, respectively, this result demonstrates the effectiveness of the ANN-based multi-objective optimization process.

Static and dynamic study of the industrial vehicle transmission adopting composite materials

The present research concerns the study of the lightening of the transmission of a commercial vehicle and in particular a truck with a power of 235 kW by using composite materials. The study was first approached numerically by defining an in-depth model with lumped parameters that encompassed all the elements of the transmission with their respective performances, then numerical analyses were conducted to confirm the results obtained analytically. The dimensions of the driveshafts in the transmission were chosen considering three variables, which affect the static and dynamic behavior of the transmission. These are the stiffness, the static and fatigue safety coefficient, the eigenfrequencies and the torsional buckling load to obtain a component, designed with the new materials with the same performance as that made of steel. The results show that using transmission shafts made of composite materials (particularly carbon fibers) results in a final weight savings of up to 30 % compared to the identical components made of steel with equal static and dynamic performance.

Wireless Solar Charging Station and Battery Management using Arduino

Electric-powered vehicles will help reduce greenhouse gas emissions and increase fuel prices. The main purpose of wireless transmission in electric vehicles is to transfer power over a small distance. The wireless power transmission system consists of a transmitter and receiver part that is separated by a small distance. Wireless transmission technology uses a flexible electromagnetic field. This electric field is created in a free environment that carries a fixed amount of money that creates a magnetic field around it and this field contains energy in it and the EMF is generated between the coils and transmitted to the receiver. BMS is a battery management system. In EV vehicles we use two batteries such as master and slave. The first preference is given to the master battery in BMS. If the master battery charge comes down automatically the relay will switch from battery

Dynamic Characteristics and Fault Mechanism of the Gear Tooth Spalling in Railway Vehicles under Traction Conditions

Gear tooth spalling is one of the inevitable fault modes in the long-term service of the traction transmission system of railway vehicles, which can worsen the dynamic load of the rotating mechanical system and reduce the operating quality. Therefore, it is necessary to study its fault mechanism to guide fault diagnosis scientifically. This paper established a planar railway vehicle model with a traction transmission system and an analytical time-varying meshing stiffness (TVMS) model of the spalling spur gear. Then, it analyzed the dynamic characteristics under traction conditions. The research found that the spalling length and depth affect the amplitude of the TVMS at the defect, while the width affects the range of the TVMS loss. The crest factor is the best evaluation indicator in ideal low-noise environments due to its sensitivity and linearity, but it is not good in strong-noise environments. Similarly, a time–frequency analysis tool cannot significantly detect the sideband characteristics that are excited by spalling. After high-pass filtering, the root mean square and variance exhibit excellent classification and vehicle speed independence in strong-noise environments. This research achievement can provide adequate theoretical support for feature selection and making strategies for fault diagnosis of railway vehicle gear systems.

The double-flow electromechanical transmission of tracked vehicle

BACKGROUND: Specific demands to ensure high mobility and low energy consumption while cornering are given in the process of development transport and special tracked vehicles. Therefore, improvement of values of these parameters is a relevant objective. The mentioned parameters are directly dependent on the chosen type of transmission.
 AIM: Derivation of transmission kinematic schemes that provide the best opportunities to ensure the quality of tracked vehicle cornering control with relative simplicity of design.
 METHODS: Derivation of transmission kinematic schemes and analytical evaluation of expected transmission properties were based on fundamentals of the theory of ground vehicle dynamics.
 RESULTS: The kinematic diagram of a double-flow transmission and rotation mechanism for a transport vehicle with two engines is proposed. The proposed scheme is applicable for tracked chassis, wheeled vehicles using the skid-steering method. The proposed principle of transmission construction can be adapted for a ship with a hybrid powerplant. The modes of operation of the proposed mechanism are presented, its main kinematic and power features are given. An assessment of the required power of the traction electric motor as part of a hybrid powertrain of a transport tracked vehicle weighing 4550 tons was carried out. Special attention is paid to the problem of the possibility of manufacturing a hybrid powertrain with the proposed transmission based on components, the production of which has been produced in the Russian Federation.
 CONCLUSIONS: The proposed transmission scheme may be used for development of new machinery as well as for upgrading of existing vehicles. Main advantages of the proposed scheme are simplicity, compactness, and engine functions duplications. Specific advantages for a transport vehicle with an regenerative steering system are ensuring the mechanical energy recuperation during cornering and braking and ensuring turning the production of a pivot turn.

Harmonic Analysis of Electric Transmission System of New Energy Vehicle

In order to improve the cruising range of new energy electric vehicles and solve the low efficiency of electric transmission system in low-speed driving stage, a space vector pulse width modulation algorithm is proposed. The simulation model is established by Matlab/Simulink software, and the test parameters of electric transmission system in the actual driving process of new energy electric vehicle are analyzed, and the harmonic distribution of line voltage of electric transmission system and the influence of battery bus voltage on harmonic content are explored. The actual test results show that reducing the difference between the bus voltage and the fundamental line voltage under actual electric transmission can reduce the harmonic content and improve the system efficiency. According to the characteristics of power generation system, a reliable motor optimization scheme is proposed to reduce harmonic content to improve the efficiency of electric transmission system of new energy vehicles.

Dynamic Evolution Characteristics of the Gear Meshing Lubrication for Vehicle Transmission System

The transmission in automobiles is the core component to ensure operational stability. Heat accumulation in the meshing process will reduce the transmission efficiency and affect the service life. Here, the essential physical process to improve transmission heat dissipation is the dynamic evolution process and the thermal transfer characteristics of lubricating oil fields during gear meshing. This paper presents a modeling and solving method for gear meshing lubrication and thermal transfer features based on the volume of the fluid model and piecewise linear interface construction (VOF-PLIC). The dynamic mesh technique combines spring smoothing and reconstruction to optimize the numerical solution process. The dynamic evolution law of gear meshing lubrication and thermal transfer is obtained by analyzing the lubrication evolution process under different speed/steering conditions. The results show that the proposed modeling and solving method could well reveal the lubrication and thermal transfer laws of the gear meshing. The temperature of the gear meshing regions was higher than that in the other regions, and the lubrication temperature showed an increasing linear trend with the stirring process. As the gear speed increased, the meshing resistance moment increased, the transmission power loss increased, and the lubrication oil temperature was larger than that of the gearbox. The power loss under the clockwise rotation of the driving gear G4 was higher than that under the counterclockwise rotation of the driving gear. The relevant results can provide theoretical references for the dynamic analysis of automotive transmission lubrication and technical support for gear profile design and lubrication optimization.