Research On Constant Speed Control Of Pump Control Motor System Under Different Loads

Pump control motor speed control system is widely used in the field of construction machinery.However,the pump control motor speed control system is a high-order,non-linear,time-varying system.The load conditions are complex and changeable.It is difficult to obtain satisfactory control results by using conventional control algorithms to control it.The domestic research on the pump-controlled motor system is mainly focused on the parameter and power matching,and the control method also uses a single control strategy.Therefore,it is of great significance to study which control strategy the pump control motor system has the best effect under different load conditions.The main research contents and methods are as follows:(1)The method of theoretical modeling is used to model the pump control motor system,the open and closed loop transfer functions of the system are solved,and the stability of the system is judged according to the transfer function of the system.(2)Establish a control framework for the system and propose the flexible use of four control algorithms,such as classic PID control,expert PID control,genetic algorithm PID control,and BP neural network PID control,to realize the pump-controlled motor system under different load conditions Constant speed control.(3)According to the principle of joint simulation,the AMESim physical model of the system is established,and the controller module of the system is established in Simulink.Through the joint simulation data interface module,the physical model of the system is ingeniously connected with the control module to form a closed-loop control system.(4)Through the joint simulation of AMESim and Simulink and pure Simulink simulation,the feasibility of the control method is tested.The dynamic performance of the system under no-load and different external loads(abrupt change,slow change,alternating change)is analyzed.The optimal control strategy corresponding to the system under different load conditions is obtained.Through the analysis of the simulation results,the response time of the expert PID control system is the shortest under the no-load state.Under different external load conditions,when the external load is a sudden load,the expert PID control has less overshoot than theother three control strategies,and the time to recover to the new equilibrium state is shorter.When the external load is a slowly varying load,the genetic algorithm PID control has the best effect.When the external load is an alternating load,the BP neural network PID control has the strongest anti-interference ability.In addition,regardless of the no-load state or different external load states,the response time of the system co-simulation is longer than the simple Smulink simulation time.Finally,by comparing the advantages and disadvantages of the two simulation methods,it is found that the use of joint simulation methods to analyze and study the hydraulic system can obtain more reliable simulation results.