Research On The Design Methodology Of Hybrid System For LHD

In this paper,combined with the design process of the 14-ton hybrid power LHD,the design problem of the hybrid power system of the LHD was studied from the perspective of the whole process and method.The key problems of hybrid power system design are solved in several aspects,such as scheme design,working condition analysis,detailed design of sub-system,etc.,and the design effect is verified by prototype test.The research focuses on the process of scheme generation and design implementation.First of all,in the conceptual design stage,according to the characteristics of mechanical,electrical and hydraulic composite system design of LHD,combined with the characteristics of construction machinery system.A scheme design model based on AD-TRIZ was proposed,and the analysis and design method of the LHD system was obtained by combining the top-level parallel decomposition method of the functional Structure-Energy-Information dimension.This method is used to systematically analyze the LHD,and many design solutions are obtained.The conceptual design phase of the LHD hybrid power system was completed.Then,in order to meet the requirements of the hybrid power system from scheme design to detailed design,the working condition of the LHD was analyzed,and the design requirements were in-depth from qualitative function description to quantitative parameter description.The cycle curve of the LHD is established by theoretical calculation and virtual prototype simulation.Compared with the test results,the actual situation increased successively.However,due to the different degree of input information required,it can correspond to different stages of product design and development.Subsequently,the key problems of the detailed technical design of the hybrid power system of the LHD are studied from three dimensions of structure,energy and information.According to the design requirements of LHD hybrid power system,the system design and component selection of 14t hybrid LHD are completed from the aspects of system configuration determination,parameter matching of key components,system layout and control structure.For the hybrid power system drive traction control needs,studied the traction control strategy of the electric drive system of the scraper,and proposed the torque control strategy of the power closed-loop drive system based on the speed judgment.According to the characteristics of the independent driving system of the front axle and rear axle of the LHD,a coupling model of the driving system with variable alxe load was established,and the effect of the control strategy is verified by simulation.In order to complete the energy supply function of the hybrid power system,the energy dimension performance of the power system is controlled through the reasonably designed energy control strategy in the information dimension.By analyzing the power chain relationship of the hybrid power system in this paper,the input and control parameters required by the control system are determined.A power following control strategy of double-layer control structure is proposed.By judging the state of the system,the engine speed and generator power are controlled to ensure the performance of the system and reduce the fuel consumption.In order to improve the robustness of nonlinear system control,a fuzzy logic control strategy is established according to the working characteristics of the scraper.By comparing the effects of the two control strategies through the simulation test,the two strategies can effectively achieve the control objectives and ensure the normal operation of the system.Finally,the design effect of hybrid power system of LHD is verified by test method.The V mode based internal-external layer verification test flow is established,and the design of hybrid power system is tested and verified from the design stage and prototype test stage respectively.At the design stage,the key points of each dimension in the design of hybrid power system are verified by means of simulation and bench test.In the prototype stage,the key parameters are verified by type test method in the test field.The performance test under typical working conditions is adopted to verify that the hybrid power LHD has better static and dynamic fuel economy than the traditional diesel LHD,with fuel saving of 25.9%.The environmental applicability and operation economy of the hybrid power system of the LHD are further verified in the mine industry test.