Research On Energy Management Strategy Of Series Diesel Electric Hybrid Tractor

Tractors,as the most important power machine in the development of agricultural mechanisation,are facing two major problems of fossil energy shortage and pollution discharge.With the improvement of agricultural mechanisation in China,the development of hybrid tractors is imminent,which is not only conducive to saving fossil energy and reducing damage to the environment but also conducive to the sustainable development of energy.At present,series hybrid tractors have been developed abroad,and the research and development of hybrid tractors in China are still in the research stage of test benches.The research on energy management strategies of hybrid tractors is rare.Given these problems,this thesis studies the energy management strategy of series diesel-electric hybrid tractors proposes SOC power-following and fuzzy reasoning energy management strategies and analyses the fuel economy of hybrid tractors under ploughing conditions.This thesis mainly studies through theoretical analysis,and bench test and software joint simulation.The main work and conclusions are summarised as follows:(1)The overall design and working resistance analysis of series diesel-electric hybrid tractors.Through the structural analysis of the existing hybrid tractor drive system,the series structure is selected for research,the rear wheel independent drive scheme of the wheel motor accelerator is determined,and the selection and parameter matching of the drive system components are selected.For the dry farming operation under medium soil in Jiangsu,the working speed was set according to the tractor design manual,and the effective resistance received during the tractor ploughing operation was analysed.(2)Design and test analysis of series diesel-electric hybrid tractor test bench.Through the structural analysis of the hybrid tractor test rig,the overall design of the test rig is completed,including the overall layout and loading system design.After the demand function analysis of the testbed measurement and control system,the design of the measurement and control system is carried out using LabVIEW software.The performance test and efficiency test of the main components of the drive system was carried out on the test bench.The characteristic curves and efficiency curves of the various components of the drive system were drawn,which laid the foundation for the formulation of the energy management strategy.(3)Energy management strategy formulation and modelling of series diesel-electric hybrid tractors.The working model of the hybrid tractor is analysed,and the energy flow roadmap is drawn to give a theoretical basis for the formulation of the energy management strategy.Based on the energy management strategy of the hybrid vehicle,and the traditional fixed-point and power-following strategies,the SOC power-following and fuzzy reasoning energy management strategies were carried out,and the analysis and strategy were formulated.The simulation model was built in MATLAB/Simulink software,and the three energy management strategies were embedded in the simulation model as the energy management strategy.The joint simulation laid the foundation.(4)CRUISE modelling and co-simulation analysis of series diesel-electric hybrid tractors.Establish the physical model of the hybrid tractor in the CRUISE software,add the ploughing device;introduce the modified UDC-CVT working condition into the cycle working condition simulation setting module,and set the cycle number to 20,the working time is 1h;the energy management strategy.The simulation model is compiled and then imported into the CRUISE software for co-simulation.According to the joint simulation results,under the fixed-point energy management strategy,the SOC of the battery pack is 0.65-0.5876,the fuel consumption of the tractor is 6.47 L/100km,the power consumption is 40.03 kWh/100km,and the comprehensive fuel consumption is 19.813 L/100km.Under the SOC power-following energy management strategy,the SOC of the battery pack changes from 0.65 to 0.5880,the fuel consumption of the tractor is 5.93 L/100 km,the power consumption is 39.81 kWh/100 km,and the overall fuel consumption is 19.200 L/100 km.Under the energy management strategy,the initial SOC of the battery pack is 0.65-0.6036,the fuel consumption of the tractor is 5.26 L/100km,the power consumption is 29.77 kWh/100km,and the comprehensive fuel consumption is 15.183 L/100km.After calculation,the fuzzy reasoning energy management strategy The fuel economy of the whole machine is 20.92%higher than that of SOC power follow-up,which is 23.37%higher than the fixed point type,which verifies the effectiveness of the strategy.