Research On Barrel Temperature Control Of Wood Plastic Extruder With Variable Universe Adaptive Fuzzy Control

Wood plastic composite material is a new type of green environmental protection material, it has been applied in the field of storage, building, packaging and so on. However, in the actual production, the lack of wood plastic extruder barrel temperature control precision has limited the large-scale and high-quality production of wood plastic composite. so, to seek a high efficiency and high quality production plan is the most effective way to reduce the relative cost and expand the scope of the promotion.The thesis comes from the key technology research and demonstration of green energy-saving wood plastic doors and windows of national forestry welfare industry research special(Item No.201204802),According to the analysis of wood plastic composite material extrusion process and in-depth study of the characteristics of extruder temperature control,it is concluded that the temperature control precision is one of the important factors that affect the yield and quality of the product. In this paper, wood plastic composite material extrusion temperature machine as the research object, by the improvement of the algorithm, to achieve control accuracy and reduce the fluctuation of system to obtain an optimal control scheme.In this paper, a common extrusion temperature control program-manually adjustable two-position control, PID control, fuzzy control scheme is analyzed and simulated in MATLAB comparison, the results show that commonly used extrusion temperature control algorithms are unable to achieve expected control accuracy.Therefore, this paper presents the application of variable universe adaptive fuzzy control algorithm in the control of extrusion temperature.Extension S function in MATLAB, based on variable universe adaptive fuzzy control algorithm of WPC extrusion temperature control system simulation,the simulation results show that the method of variable domain adaptive fuzzy control algorithm in different expansion factor selection greatly affect the control effect, and in the vicinity of the zero point the algorithm can produce an uncontrollable area.To further enhance the performance of the controller,by analyzing the transient and steady state parameters of the variable universe adaptive fuzzy control system,combined with problems that exist in the practical application of variable universe adaptive fuzzy control,for the difficulty in scaling factor design of variable universe adaptive fuzzy control algorithm,sign function is introduced,design supervised control and enter the β adaptive law after the correction factor,to improve the algorithm of variable universe adaptive fuzzy control.Compared it with the traditional PID control,fuzzy control,variable universe adaptive fuzzy control algorithm.Simulation results show that the optimized extrusion temperature control system based on variable universe adaptive fuzzy control in the case of fewer fuzzy rules,can effectively improve the control precision and production efficiency,is conducive to the improvement of extrusion plastic product quality,have a very important significance for the promotion of green wood plastic composite products.