Multi-motor Position Synchronization Control Technology And Application

Multi-motor synchronous control is widely used in industrial control,automobile and smart home,etc.Its synchronous performance is directly related to the quality of products.In this thesis,multi-motor synchronous control is studied in terms of multi-motor synchronous control structure and motion control algorithm,taking multi-motor lifting table as the research object.First,the working principle of brushed DC motor is analyzed and an equivalent mathematical model is built.For the position control system of the brushed DC motor,a three-closed-loop(current loop,speed loop and position loop)control structure is used for control,and the parameters of each closed-loop PID controller are tuned.Then,this thesis designs a load torque observer to observe the motor load torque in real time for the purpose of synchronizing the position control of four motors of the lifting table,and proposes an improved fuzzy PID controller based on the load torque observer,and applies it to the speed loop of the three-closed-loop position control system.Simulation experiments are conducted with the aid of Matlab/Simulink for the position control system with PID controller for the speed loop,fuzzy PID controller and improved fuzzy PID controller respectively,and the simulation results show that the improved fuzzy PID controller improves the following performance of the position control system compared with the PID controller and fuzzy PID controller.In order to improve the synchronization performance of multi-motor position synchronization system,the commonly used motor synchronization control structures are simulated and analyzed.On the basis of the adjacent cross-coupling control structure,the compensation weight coefficient of its position compensator is improved,and the simulation results show that the improved adjacent cross-coupling control structure further reduces the position synchronization error and achieves good position synchronization effect.Finally,the position curves of the four motors of the lifting table are planned,the improved fuzzy PID control algorithm is applied to the speed closed loop,and the soft start and soft stop are used to solve the problems of excessive starting current and mechanical shock during deceleration of the lifting table,which completes the hardware and software design of the position synchronization system of the four motors of the lifting table.The experimental results show that the maximum position error of the four motors position synchronization system of the lift table is 4,6 and 8 pulses error under light load,different load and heavy load respectively,each pulse corresponds to 0.125 mm,i.e.the maximum position error is 0.5mm,0.75 mm and 1mm respectively.and a good position synchronization effect is achieved.