Multi-motor Speed Coordinated Control Based On Deviation Coupling Structure

With the continuous improvement of the level of industrial production automation,in the field of traditional industrial drive,multi motor cooperative control technology has gradually replaced the traditional single shaft motor drive technology.For a multi-motor cooperative electric drive system,because of the less control volume and the addition of other material properties and mechanical friction,the control of the multi motor system is relatively easy and the control accuracy is relatively high.While in the existing parallel control,master-slave control,virtual shaft control,cross coupling control and relative coupling control structure,because of the high coupling performance and the many motors to control,relative coupling control structure is widely accepted and used in multi motor synchronous speed control,and is also the main direction of future research.In the traditional relative coupling structure,speed compensation mechanism and compensation module is complex,and the amount to online calculate is great;and the stable operation of the system of uneven load starting in the motor system load disturbance,the system will produce large synchronous errors resulting in synchronization performance is bad.To solve these problems,this article will replace the given speed and compensation module in the traditional structure to the synchronization error compensator.The compensation mechanism is the average speed of a motor speed and motor do all difference,difference through a separately controlled synchronous performance system of proportional integral controller,the compensation to the output end of the motor speed controller the load disturbance,such that the synchronization error is too large to solve the problem of the stability of the system operation.And increase the output selector in the speed loop controller part of the system at the time of starting torque,high rotating speed motor given desaturation,slow motor torque saturation,so as to solve the system at the time of starting the motor load due to larger systems both make the same step error problem.Finally,the three motor experimental platform was built,and the comparative experiment analysis of the traditional relative coupling structure and the improved relative coupling structure was carried out on this platform.The experimental results show that compared with the traditional structure,the improved relative coupling multi-motor control system can effectively reduce the synchronization error and improve the synchronization performance of the system when the motor load is uneven starting and the load of the system is disturbed.The improved structure is suitable for control occasions with high requirements for synchronization of multi motor systems.