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Luo N.-N.,Harbin Institute of Technology | Zhao L.-J.,Harbin Institute of Technology | Jiang J.-H.,Harbin Institute of Technology | Zhang J.,Harbin Institute of Technology | Yu A.-C.,Tianjin Research Institute of Construction Machinery
Huanan Ligong Daxue Xuebao/Journal of South China University of Technology (Natural Science) | Year: 2014

The whole vehicle performance depends on the topological structure and the control strategy of hybrid power system. In this paper, a series-parallel hydraulic hybrid system is proposed on the basis of ground torque coupling mode. This kind of hydraulic hybrid system is suitable for the working condition of urban public traffic. In order to meet the instantaneous power requirement of vehicles and achieve the optimal global economy, an energy management strategy is proposed for the whole vehicle. Then, to simplify the system structure, the progressively hierarchical control method is adopted according to the hybrid system theory. Finally, through the Matlab/Simulink/Statflow co-simulation, a forward model of the whole vehicle is established and the fuel economy and the dynamic performance of a whole vehicle are analyzed under the ECE city driving cycle. The results show that the proposed system and strategy can significantly improve the engine output characteristic and effectively increase the fuel economy and the instantaneous dynamic performance of the whole vehicle. ©, 2014, South China University of Technology. All right reserved. Source

Luo N.-N.,Harbin Institute of Technology | Zhang J.,Harbin Institute of Technology | Jiang J.-H.,Harbin Institute of Technology | Zhang Q.-R.,Harbin Institute of Technology | Yu A.-C.,Tianjin Research Institute of Construction Machinery
Journal of Donghua University (English Edition) | Year: 2014

Simple and efficient energy management strategy is the key to ensure hybrid vehicle performance. Based on hybrid dynamical system theory and the concept of finite state mechanism, power split hybrid connected structure hydraulic hybrid system was proposed and described. In order to meet the demand for driving, the layered advanced control strategy was proposed in this paper, which referred to vehicle driving experience. Using Matlab/Simulink/Stateflow hybrid modeling method, the economy performance and the acceleration performance of the vehicle under the typical city driving cycles were carried on the simulation analysis. The results show that the proposed topology and control strategy can obviously improve engine output characteristic, effectively enhance the vehicle's instantaneous power performance and economy, and also has a better adaptability in different traffic environments. Copyright © 2014 Editorial Department of Journal of Donghua University. All rights reserved Source

Wang X.-J.,Harbin University of Science and Technology | Xian C.-F.,Harbin University of Science and Technology | Wan C.-L.,Harbin University of Science and Technology | Zhao J.-B.,Harbin Institute of Technology | And 2 more authors.
Journal of Harbin Institute of Technology (New Series) | Year: 2014

In order to consider the influence of the continuous rotary motor electro-hydraulic servo system parameters change on its performance, the design method of backstepping adaptive controller is put forward. The mathematical model of electro-hydraulic servo system of continuous rotary motor is established, and the whole system is decomposed into several lower order subsystems, and the virtual control signal is designed for each subsystem from the final subsystem with motor angular displacement to the subsystem with system control input voltage. Based on Lyapunov method and the backstepping theory, an adaptive backstepping controller is designed with the changed parameters adaptive law. It is proved that the system reaches the global asymptotic stability, and the system tracking error asymptotically tends to zero. The simulation results show that the backstepping adaptive controller based on the adaptive law of the changed parameters can improve the performance of continuous rotary motor, and the proposed control strategy is feasible. Source

Guo-Lu L.,Hebei University of Technology | Zhi-Qiang Z.,Hebei University of Technology | Zhi-Qiang Z.,Academy of Armored force Engineering | Zhi-Qiang Z.,Tianjin Research Institute of Construction Machinery | And 4 more authors.
Tribology International | Year: 2013

The aim of present study is to monitor rolling contact fatigue (RCF) behavior and analyze failure mechanism of the coating by acoustic emission (AE) technology. The results show that AE amplitude and counts are sensitive to RCF damage process, and variation regularities are different during different damage stages. Spalling is the key failure mode. RCF damage process is composed of five stages, such as elastic deformation, plastic deformation, crack initiation and propagation, crack stable growth, and unstable growth. Fatigue cracks are liable to initiate and grow along the direction of defects within the coating, such as pores and cracks. © 2013 Elsevier B.V. All rights reserved. Source

Jin H.-Z.,Harbin Engineering University | Su X.-Y.,Harbin Engineering University | Yu A.-C.,Tianjin Research Institute of Construction Machinery | Yu A.-C.,Harbin Institute of Technology | Lin F.,Heilongjiang University
Dianji yu Kongzhi Xuebao/Electric Machines and Control | Year: 2014

From the economy and security standpoints, the paper presents an automatic mooring positioning scheme that can find out the offshore platform position accurately and rapidly on the premise of tensions' uniform distribution. In the scheme, the optimal tensions were regarded as the thresholds of switching the mooring lines. Considering the time-variance and uncertainty of the multiple-input and multiple-output positioning system under the random disturbance, the fuzzy strategy was used to control the retraction and release of the mooring lines. The improved genetic algorithm which can improve the optimization efficiency and convergence was adopted to optimize the tension, and the genetic algorithm was improved from two aspects: first, the method based on contraction was used to generate the initial population; second, local search was adopted in standard genetic algorithm.The simulation results show that the scheme is effective to balance the distribution of tensions and keep the position of offshore platform. Source

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