The Tension Control Research And Realization Of Square Li-on Battery Winding Machine

Since the advantage of light-weight, high-capacitance, long-life and zero-pollution,the lithium-ion battery has been widely used in the world. But the key equipment for production of lithium ion battery——winding equipment for the core of lithium-ion battery, manual and semi-auto equipment are still as the principal ways in China. The performance figures such as compactness and service life are so low and difficult to meet the needs of the production and living.In this thesis, the batteries deformation problem that is the typical difficult problem of the square lithium-ion battery automatic winding machine is introduced, and current situation and development of the tension control in related field at home and abroad is analyzed.First, the traditional tension control system in square lithium-ion battery automatic winding machine is analyzed, the essence of which is how to get the synchronous linear velocity, constitute a PID closed-loop control system by the position feedback from the potentiometer in tension roll and the release system. However, the special shape of square needle leads to a large linear velocity range, then the deformation of the batteries. According to the uncontrollability of the linear velocity, a new tension control system is designed, a open loop control in rolling system is added. Using the mechanism model and the BP neural network identification method, the rolling system module of constant linear velocity is researched.Secondly, the dynamic module in the rolling process is analyzed, the theoretical module between the angular velocity and rolling linear velocity is established, so we get the angular velocity curve while the rolling linear velocity is constant. Then, the input and output data are collected to establish a BP neural network inverse model. Through the neural network model simulation, the correctional angular velocity curve is got.Finally, through many experiments in the square lithium-ion battery automatic winding machine, a good result for tension control has been achieved.