Simulation And Optimization Of High Speed On/off Valve In Electronic Limited Slip Differential

The electronic limited slip differential has great advantages in terms of vehicle operation stability and driving efficiency,and is increasingly used in various models.As the core component of the electronic limited slip differential,the high speed on/off valve directly affects the limited slip performance of the electronic limited slip differential due to its rapid response and precise control of pressure and flow.In this paper,theoretical derivation,joint simulation and other methods are used to explore the factors affecting the proportional adjustment and time response characteristics of high speed on/off valves in electronic limited slip differentials,and the control and response performance of high speed on/off valves are improved by optimization algorithms.At the same time,a hydraulic test platform was built to test and analyze its basic characteristics such as pressure and flow.The main research contents of this paper are as follows:(1)According to the analysis of the working principle and structural characteristics of the high speed on/off valve in a certain type of electronic limited slip differential,the mathematical models of the high speed on/off valve in electric,magnetic,mechanical and liquid are respectively established.Which provides theoretical basis for the joint simulation research in this paper.In addition the timeresponse curve of the valve spool displacement for high speed on/off valve under lowfrequency pulse width signal and high-frequency pulse width modulation signal is analyed.(2)According to the hydraulic circuit of the electronic limited slip differential,the simulation model of the high-frequency PWM high speed on/off valve is established in Simulink and AMESim software respectively,and Simulink/AMESim co-simulation is carried out to analyze the influence of main structural parameters of the high speed on/off valve on its proportional adjustment function,which is reflected in the influence on the suspension position of the spool and the effective duty cycle working range.By analyzing the influence of the driving voltage,the spool mass,the coil resistance and the initial air gap on the closing lag time and closing time of high speed on/off valve,it provides a theoretical reference for improving the control performance and time response characteristics of high speed on/off valves.(3)According to the MOSA optimization algorithm,the structural parameters of the high-frequency PWM high speed on/off valve are optimized.By establishing the optimization objective function of the high-speed switching valve and the AMESim optimization simulation model,the closing lag time and closing time of the high speed on/off valve are obviously shortened from the optimization result,and the maximum electromagnetic force is also greatly improved when the on-off valve is operated,which provides a basis for improving the proportional adjustment function and time response characteristics of the high speed on/off valve.(4)Design and build a hydraulic test platform for high-frequency PWM high speed on/off valve,introduce the composition and principle of the hydraulic test bench,and analyze the opening pressure and rebound pressure of the high speed on/off valve controlled by this high-frequency pulse width signal at different duty cycles,test the no-load flow characteristics of the high speed on/off valve,and verify the proportional adjustment function of the high speed on/off valve under high-frequency PWM control from the flow control angle.