Research On State Parameters Estimation And Slip Ratio Control Method Of Three-wheel Drive Electric Forklift

As industrial vehicles,forklifts are widely used for cargo handling and unloading.Electric forklifts are increasingly favored by the market because of their energy saving,environmental protection and flexible operation.For electric vehicles,the problems of vehicle state parameters estimation and slip ratio control methods are the hot spots of active safety control technology.At the same time,active safety control technology plays a very important role in the stability of industrial vehicles.This dissertation takes a company's three-wheel drive electric forklift as the research object to conduct an in-depth study on the active safety control technology of electric forklift.Firstly,the dynamic model of electric forklift is established based on Newton's kinematics principle,and based on this,a suitable nonlinear tire model is selected for the research topic of this dissertation,which provides a model platform for the control method.Secondly,for the problem that the sensor of the electric forklift is not rich and the state parameters of the forklift are difficult to measure,a suitable nonlinear filter estimation algorithm is selected to estimate the parameters of the electric forklift.The original filtering estimation algorithm is optimized because of the influence of time-varying noise during the actual driving process,and the filtering effects of different filtering algorithms are simulated and compared under Matlab/Simulink simulation platform.In addition,for the different characteristics of the sliding mode control law of vehicle acceleration and deceleration,a function is designed to approximate the slip ratio and an integrated sliding mode controller is designed.Considering that the sliding mode controller has the problem of system chattering and the selection of the approaching law parameters,a simulated annealing genetic algorithm is used to optimize the approach law parameters of the sliding mode controller.Finally,the slip ratio control effects of different control algorithms under different working conditions are compared under the Matlab/Simulink simulation platform.