Study On Electro-Hydraulic Control System Of CVT Base On CAN Bus

The technology of AUTO electronic control and AUTO net have been the sign of the development of modern vehicle.Based on the developing of every assembly control system during the end of last century and the begin of this century,it comes the time of the development of whole vehicle system control and AUTO net communication.In this backdrop condition,only under the surrounding of whole vehicle control can the design and development of assembly system be outstanding in performance.As the most idea transmission,it is also the same situation for the research and development of the Continuously Variable Transmission(CVT).In theory,CVT can achieve the most idea characteristic transmission of power, Pe = FV. In fact,CVT is more well_set, simpleness,easy to manipulate and control,cheaper, efficiency and low exhaust than the other automotive transmissions ,such as AT,AMT and DCT.So,it will bring grate benefits both in economic and society for the research and development of CVT.In the development and research of CVT,the electro-Hydraulic control system is the kernel technology and also key technology.The performance of the electro-hydraulic control system decides the performance of CVT.And so ,it were designed and developed for the electro-hydraulic control system of CVT base on CAN bus and the data collection system basedon interrupt control which can provide controls parameter for the vehicle from the point of view of whole vehicle control in this thesis.The main content of research include those as below:(1) Based on experiment and theory research the control strategy and control way were improved and the fuzzy self-adaptive PID controller was developed. It was analysed from the view of actual control for the control strategy and control way with real value of use and put forward for the question of control research adout the driver's intention when controlling the clutch and ratio.The researching shows that using the way of fuzzy theory analysis , the controls parameter can be confirmed accurately , the running state of vehicle and the operating intention can be analyzed correctly.The self-adaptive controller can change the PID parameter based on the result analyzed by the fuzzy controller and make the CVT controlling more accurate.(2) Base on the control mode of whole vehicle it was designed and developed for the CAN bus communication and the CVT was put on the whole vehicle control desk.In the whole vehicle control desk,CVT is a nod of CAN bus communication.In the thesis it was studied detailedly for the CAN bus communication principle and designed for the software and hardware of CAN bus communication utilizing the embedded CAN controller.(3) The data collection system base on interrupt control was developed under the mode of whole vehicle control and CAN bus communication.The predominance of the data collection system developed in this thesis is the interrupt control test to the revs.It can be changed for the way of interrupt test by two as timming test and counting test and the accuracy of low revs and high revs can be guaranteed.(4) The electro-hydraulic control system of CVT wasdeveloped.Aim at the characteristic of high speed on-off valve it was analyzed for the control way and the software and hardware of how to realize the control of clutch,ratio and clamping force from the point of view of real control. Especially, it was analyzed for the problem of ratio variety rate control in the process of shifting of CVT and identifying the intention of the driver.Those made the electro-hydraulic control system achieve the requirement of real control more well and have high using value.(5) A rig test and real AUTO test to the electro-hydraulic control system and the data collection system were tried out .In the test ,the recessive question was gotten rid of and the design scheme was improved ,and the controls parameter was optimized continuously.The test and research had proved that the designed data collection system works more precision sensitivity ,reliability and easy to adjust.The test and research also proved that the designed electro-hydraulic dontrol system can identify the driver's intention well and the real ratio can follow up the target ratio more well and also the system satisfies the need of real control.