Permanent magnet synchronous motor (PMSM) servo drive system has been widely used for industrial sewing machines. The conventional control method is PID, which has some disadvantages such as large overshoot, bad robustness. In this paper, a servo control of the industrial sewing machine system based on the active disturbance rejection control (ADRC) is proposed, which can arrange the transient process, estimate and compensate the uncertain internal and external disturbance. It can highly enhance the dynamic performances of the system. Based on the Matlab/simulink software, the simulation results of the industrial sewing machine control system proved the effectiveness and robustness of the ADRC control strategy.
With the rapid development of the world textile industry, the research on industrial sewing machines have been focused on higher precision, more energy-saving, lower cost, higher speed, multiple-function, more intelligence. In order to achieve all these performance indexes, the main problem is to develop an effective servo system. And the PMSM based servo systems have attracted more and more researchers, for which has several inherent advantages compared with other types electric machinery, such as high power density, high power factor, high torque to current ratio, high efficiency, low inertia, rugged construction, easy for maintenance and so on[1,2]. The PID control is one of the early developed control strategies. Due to its simple algorithm, good robustness and reliability, it has been widely used to design position, speed and electric current loop controller in industrial sewing machine servo system. And classic PID control based, such as increment PI control, fuzzy PID control, Neural PID control ,multi-segment PI control are also adopted[3,4]. However, the classical control strategies have some disadvantages, such as, large overshoot, long adjustment time and so on. It is difficult for the PMSM servo system to realize high precision control. PMSM servo system is a typical non-linear time-variant control system. Many intelligent control methods such as fuzzy control, self-adaptive control, neural network control, sliding mode variable structure control, genetic algorithm control are adopted to solve the problems.Many scholars haveone a lot of meaningful researches on these control methods [5,6]. But it still has some difficult to realize. The ADRC can not only arrange the transient process, but also estimate and compensate the total disturbances on the system, which can highly improved the performance of the PMSM servo system. In this paper, ADRC is used as a speed loop regulator in the industrial sewing machine servo control system[7,8]. Simulation results indicated that, compared with conventional PID control servo system, the proposed control method has better dynamic performance.VS Sewing Machines
The position control of the industrial sewing machine system based on the ADRC is shown in Fig.2. Proportional control is adopted to the position loop, and the PI control is adopted to the current loop. Simulation results have been done in the Matlab/simulink. The parameters of PMSM are as follows: np=2, Rs=3.4 Ω, Ld=8.317 mH, Lq=5 mH, J=0.8*10-3 kg.m2, ψf=0.175 Wb. The ADRC parameters are chosen as follows: 0k=10, pk=2.0, ik=6.6, 21k=1200,22k=15000, 5.010==aa, 05.010==δδ, b=10000, TL=5 N.m. Fig.3~ Fig.7 show the dynamic and steady state performance of the servo control of the industrial sewing machine based on the ADRC of the speed loop. The expected speed ismin)/(1300r=ω, and the stop position is 21000 rad. Fig.3 shows the speed curve of the rotor. From which we can see that the speed of the system has no overshoot, and the system has a good dynamic response. Fig.4 is the curve of rotor position, which shows that the ADRC control system has high precision in servo control. Fig.5 shows the electromagnetic torque of the PMSM. Fig.6 shows the transient process of the expected rotor speed arranged by the TD of ADRC. is the rotor speed estimated by the ESO of the ADRC. As load torque often changed dramatically in the industrial sewing machine system, such as the type or the thickness change of the fabric will cause the load torque disturbance. It is necessary to test the robustness of the ADRC and PI controller. Fig.11 shows the rotor speed response of the ADRC and PI controller when TLchanged suddenly from 5 N.m to 10 N.m at 0.06s. From the Fig.11 we can see that the rotor speed drop of the ADRC is less than the PI controller. And it shows that the ADRC has better dynamic response and robustness than the PI controller. https://www.vssewingmachine.in/