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Number of results: 5
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Abstract

The application of active adhesion control to the traction control system of an electric train holds great appeal for maximizing longitudinal acceleration force. Most of the currently reported works regulate the adhesion between wheel and rail by adjusting the torque reference of a cascade motor drive controller, which suffers from slow speed response and excessive start torque. This article proposes a cascade-free predictive adhesion control strategy for electric trains powered by an interior permanent magnet synchronous motor (IPMSM) to address these issues. The proposed control scheme utilizes an improved perturbation and observation method to predict the time-varying wheelrail adhesion state and determine the optimal slip speed. The initial setpoint reference command from the driver master is then adjusted to a dynamic reference that continuously adapts to the predicted adhesion conditions. Finally, the predictive speed control method is employed to ensure rapid convergence of the tracking objective. The simulation and hardware-in-the-loop testing results confirm that this approach achieves excellent dynamic performance, particularly during the train start-up phase and in the high-speed weak magnetic area of the IPMSM.
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Authors and Affiliations

Jiao Ren
Ruiqi Li
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Abstract

The working environment and objects of agricultural machinery are different from those of automobiles, andagricultural machinery is greatly affected by the working environment and working conditions, and the power output systemismore complex. Agricultural machinery not only has drive output, but also PTO output and hydraulic output, whichtogetherconstitute the output system of agricultural machinery. Agricultural machinery conditions can be dividedintoroadtransportation working conditions and field operation working conditions. The working conditions of agricultural machinerycan be divided into different load conditions according to the different traction tools and whether the hydraulic andPTOwork,such as ploughing, rotary tillage, fertilization, and transportation. Therefore, developing hybrid electric agricultural machinerysystems that are suitable for various complex working conditions holds great theoretical significance and practical value. Giventhe complex working conditions of agricultural machinery systems in agricultural work and the intricate challengesindesigning hybrid agricultural machinery systems. In this paper, the two-dimensional matrix is used to represent thephysicalstructure and dynamics of the multi-channel power output agricultural mechanism. A hierarchical two-dimensional matrixmethod for the generation and screening of hybrid electric agricultural machinery systems with multi-power output powerisproposed. The components of agricultural machinery are divided into an input layer and an output layer, and these componentsare coded and defined, and then transformed into a matrix. The hierarchical two-dimensional matrix method is usedtogenerateand screen the hybrid electric agricultural mechanism type. Through the stratification of the matrix, the complexityoftheconfiguration generation is reduced, and the constraints are applied to the basic screening of the generated configurations. Therationality of the configurations obtained after generation and screening is verified by Simulink simulation. The resultsshowthat the configuration screened by this method can meet the performance requirements of agricultural machinery.
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Authors and Affiliations

Baogang Li
Jinbo Pan
Rui Sun
Yuhuan Li
Zunmin Liu
Wanyou Huang
Hanjun Jiang
Fuhao Liu
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Abstract

The demand for energy in the world is growing, and the requirements for the efficiency of energy-saving technologies used in renewable energy sources, especially prominent in terms of power electronics, are also increasing. In many renewable energy applications, high-efficiency, high-power DC/DC converters are necessary as an interface between various low-voltage sources and higher output voltage loads, e.g., in photovoltaics. The article presents a comprehensive study on reducing power losses in electric energy conversion in modified isolated and non-isolated DC/DC boost converters powered by low-voltage energy sources. The main desirable features, such as high energy efficiency, high conversion ratio, and low stress on the switches and diodes, were compared and further experimentally validated. The experimental evaluation indicates that the highest efficiency of 96.7%, with a conversion ratio of more than 10, was achieved in the interleaved boost-flyback DC/DC converter. Other investigated systems, namely non-isolated push-pull-boost converters, isolated half-bridge boost, and partially parallel boost converters, achieved slightly lower efficiency. Simultaneously, using the suggested topology, the passive component count was reduced. Furthermore, better utilization of switches and a higher conversion ratio are provided, as well as a possibility of working at a lower duty cycle compared to other step-up converter topologies. All in all, the proposed and studied converters exhibit certain advantages over other state-of-the-art solutions and thus can be competitively and effectively employed in modern low-voltage DC/DC applications such as photovoltaics.
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Authors and Affiliations

Jakub Dawidziuk
ORCID: ORCID
Michał Harasimczuk
ORCID: ORCID
Rafał Kopacz
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Abstract

With a continued strong pace of artificial intelligence, the way of formulating the flight day plan has a significant impact on the efficiency of flight training. However, through extensive research we find that the scheduling of flight days still relies on manual work in most military aviation academies. This method suffers from several issues, including protracted processing times, elevated error rates, and insufficient degree of optimization. This article provides a comprehensive analysis of automated flight scheduling using Goal Programming algorithm and details the implementation of the corresponding algorithm on the LINGO platform. The study enhances the flexibility and robustness of the model by setting bias variables, wherein the flight courses for students and instructors can be automatically and reasonably scheduled.
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Authors and Affiliations

Pengfei Sun
Jia Liu
ORCID: ORCID
Hao Nian
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Abstract

Lithium-based battery systems (LBS) are used in various applications, from the smallest electronic devices to power generation plants. LBS energy storage technology, which can offer high power and high energy density simultaneously, can respond to continuous energy needs and meet sudden power demands. The lifetime of LBSs, which are seen as a high-cost storage technology, depends on many parameters such as usage habits, temperature and charge rate. Since LBSs store energy electrochemically, they are seriously affected by temperature. High-temperature environments increase the thermal stress on the LBS and cause its chemical structure to deteriorate much faster. In addition, the fast charging feature of LBSs, which is presented as an advantage, increases the internal temperature of the cell and negatively affects the battery life. The proposed energy management approach ensures that the ambient temperature affects the charging speed of the battery and that the charging speed is adaptively updated continuously. So, the two parameters that harm battery health absorb each other, and the battery has a longer life. A new differential approach has been created for the proposed energy management system. The total amount of energy that can be withdrawn from the LBS is increased by 14.18% compared to the LBS controlled with the standard energy management system using the genetic algorithm optimized parameters. In this way, the LBS replacement period is extended, providing both cost benefits and environmentally friendly management by LBSs turning into chemical waste later.
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Authors and Affiliations

Gökhan Yüksek
ORCID: ORCID
Timur Lale

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