Fuzzy-PI double modes control to motor under minus load circumstance

In tension control system for winding machine, motor sometime works under minus load circumstance, in which electromagnetic torque acts as drive, but its direction is opposite with the rotary direction of motor because of load torque. In this paper, the minus load circumstance of motor is analyzed, and a minus load model of tension control system for winding machine is built. A novel idea of improved Fuzzy-PI double modes control is proposed. By adopting switching method at natural switching point and adjusting switching condition for Fuzzy-PI double modes control, the transient and steady states of system are improved under minus load circumstance. The design of the fuzzy controller adopted in Fuzzy-PI double modes control is described in detail. The simulation model for this control idea is built in Matlab/Simulink platform, and the results of simulation are given and analyzed. It shows this kind of Fuzzy-PI double modes control not only make system obtain good transient performance, but also obviously decrease the range of error of in steady state. This study can provide a reference for the application of fuzzy control system under minus load circumstance.