For Drum Washing Machine Series Motor Speed Control Technology Research

In recent years, because of the advantages, which are uniform washing, lower rate of wear, higher degree of automation, and can saving in water consumption and heating water, drum washing machine is more and more recognized by consumers. Series motor not only has a high torque at low-speed, but also has a high efficiency at high-speed, which met the needs of drum washing machine. Thus series motor can be used widely.In this paper, the speed control technology of series motor using in drum washing machine is studied and the debugging platform of it is designed. The main works and achievements are as follows:(1) The work and speed control principles of series motor are analysised and its model is given out. Then the speed control simulation environment of motor was established. Based on the washing process and speed requirements of drum washing machine, the simulation of PID speed control of series motor is done. The results show that:when P, I, D parameters are suitable, the basic speed requirements can be met, but for the speed fluctuation caused by the change of load torque, PID control can't get the satisfactory control effect; when the given speed is changed, there will be overshoot at speed, which is easy to lead to clothing wear.(2) Against the inadequate of PID speed control performance of series motor and debugging difficulties of PID controller, neural network inverse system is used. First, the reversibility of the speed control system of series motor is judged and the structure of this inverse system is determined.Then train the neural network to meet the requirement and use it for the simulation of system. The results show that:this method is more intuitive and convenient in the area of selecting debug parameters; compared to PID control, it can be able to better meet the speed performance indicators of system. In addition, the implementation ideas of using it in engineering have also been given out.(3) In order to meet the requirements of accelerating the debugging progress and mastering the control performance quickly, the visual debugging platform is designed, which is based on the project from Wuxi Little Swan. Then the main functions, such as the serial communication between the upper and lower machine, sending debug command, accepting current speed and displaying speed curve are achieved.