Application Of Fuzzy PI Control In Elevator Door System Based On PMSM

The elevator door-motor system is an important component of the elevator. Incurrent elevator door-motor system, the induction machine drive system is beinggradually replaced by permanent magnet sychronous motor(PMSM) drive system forthe sake of compactness. Since the PMSM door-motor drive system is driven directlywithout decelerator, the rotational inertia of the motor shaft differs greatly accordingto whether the door is loaded or not. The PI parameters are not self-adaptive and haveto be adjusted manually when it comes to different kinds of elevator, which makes theinstallation and debugging even more complicated. An improved fuzzy PI controlmethod is proposed in this paper to address this problem. Applying this method willsave lots of efforts to debug control parameters, and remarkably improve the drivesystem’s adaptability to the wide-range change of rotational inertia.At the beginning of this paper, a short introduction is given to the structure andfeatures of elevator door-motor system, as well as its mathematical model. Then thedouble closed-loop vector control system based on id0and its PI parameters’design procedures are both analysed. Considering the properties of elevator doorsystems and the relation between rotational interia and current, we came up with animproved fuzzy PI control method. Based on the vector control of PMSM, the fuzzyPI controller in speed loop can tune PI parameters automatically while the system isrunning, getting better dynamic response. Besides, by observing current when themotor is working, the gateway position can be obtained. Simulation experiments withelevator doors of different weights are undertaken by the system model built inMATLAB/Simulink. Finally, the control method is programmed in the elevatordoor-motor controller based on DSP TMS320LF2407. These methods, with the PIcontrol parameters constant or fuzzy, are compared in two different cases, betweenwhich the door weights are about10times different.Simulation and experimental results demonstrate that the modified fuzzy PIcontrol method can perform quite well on elevator doors of different size or weight,which not only can make debugging free, but also has a good control effect on thechange of rotational inertial when controlling different kinds of elevator doors.