Research Of Dual Pump Hydraulic System Of Electromechanical Coupling Transmission Based On DCT

New energy vehicle is the trend of automobile industry,and the hybrid especially the electromechanical coupling of the hybrid system,with the excellent fuel economy and power,is one of the current research focus.Electro-hydraulic control is currently the most widely used electromechanical coupling transmission shift control system,its reasonable structure and control determines the comprehensive performance of electromechanical coupling transmission.Based on the 2015 National Science and Technology Support Program,this paper research on the hydraulic system of the electromechanical coupling gearbox.First of all,this paper summarizes the development status of domestic and foreign DCT technology and hybrid technology,analysis Toyota,Honda and GM electromechanical coupling hybrid system.At the same time,research on related field at home and abroad are summarized.Then,the paper introduces the electromechanical coupling transmission scheme based on DCT,analysis the main working mode,research on the requirements of the hydraulic system.On this basis,design motor cooling circuit and cooling control,design the dual pump system.Then accomplish electric pump and mechanical pump displacement design according to the maximum demand condition of hydraulic system.Then,analysis the electromechanical coupling transmission hydraulic control valve structure and working principle,use nonlinear modeling method to establish the mathematical model of main line pressure control valve,clutch pressure control valve,shift force control valve,clutch cooling control valve,and motor cooling control valve.Based on Simulink simulation platform,build modular models.On the basis,the hydraulic control valve test bench is built,the main line pressure control valve,clutch pressure control valve and a clutch cooling control valve have been tested,and results verify the validity of the simulation model.Finally,build double pump model,hydraulic load model,vehicle model and pump control strategy,through simulation,the effectiveness of pump control strategy is verified,and the dual pump hydraulic system meet the needs of electromechanical coupling transmission.