The Research Of Brushless DC Motor Optimal Contron System Based On Improved Double Closed-Loop Controller

As the rapid development of new permanent magnetic materials,control theory,modern power electronic technology,brushless dc motor is widely used.BLDCM not only has the advantages of simple structure and high efficiency of AC motor,but also has the advantage of good speed regulation performance of brushless DC motor.Therefore,brushless DC motor plays an important role in many fields,such as household appliances,automobiles,military aviation and so on.With the constant progress of the society,the continuous development of science and technology,People to use the frequency of the motor and the motor performance requirement enhances unceasingly.Simple motor control can not meet the need,so it is necessary to motor control system to carry on the design improvement,to achieve the high precision control of the machine.Based on the analysis of brushless dc motor and frame structure,working principle,mathematical model and control method.Based on the dynamic characteristics of the motor,make sure current and speed double closed loop control structure.Control algorithm of PID algorithm as the most classic,because of its advantages such as high reliability and simple structure,theapplication in industry is still the mainstream.So this paper selected PID algorithm to control motor,on the basis of the double closed-loop structure inner add a regulator,to use classical control algorithm improve the resistance to disturbance of the control system of brushless dc motor and speed regulating performance.In addition,according to the motor dynamic response formula mathematical formula and the third chapter,created the mathematical model of the motor,and completion algorithm design and simulation experiment.Simulation results show that using the classic PID regulation,the improved double closed loop structure,the motor start and steady stage all has the very big superiority,not only to achieve the fast and safe start,improve the efficiency of the motor start;Steady-state phase at the same time,to the motor and load disturbance,the motor can quickly adjust to the given speed value,to achieve zero error,have very strong disturbance resistance,realize the high precision control of the motor.Finally,according to the conveyer belt drive system performance requirements,building experimental platform for brushless dc motor control system.Hardware system is divided into motor drive and microprocessor control module,mainly including brushless drive circuit,position detection circuit,power circuit,current sampling circuit,control chip circuit,single chip computer peripheral circuit,etc.,and it is implemented in a modular processing thinking writing and debugging experiment of the algorithm.The experimental results show that: in this paper,the design of brushless dc motor control system tocontrol high precision and good reliability,real-time,deceleration performance and precise follow a gender,the precise control of error is less than 5%.