Study on Control Strategy of Sliding Mode Variable Structure-based Electronic
Virtual Line Shafting
Zhang Changfan
1
, Xiao Yuanyuan
1
, Wen Long
1
, He Jing
1,2
1.
College of Electrical and Information Engineering, Hunan University of Technology, Zhuzhou, Hunan, 412007, China
2. National University of Defense Technology, Changsha Hunan, 410000, China
hejingzzcn@yahoo.com.cn
Abstract— The degree of precision for positioning of adjustable
rollers during pre-registering stage has direct influences on register
precision of the entire printing. The paper puts forward control
strategy of sliding mode variable structure-based electronic virtual
line shafting based on the influences of low-speed pre-register
process of shaft-less drive printing press on register precision and
the influences of nonlinearity and disturbance on synchronous
precision of printing process. The experimental results demon-
strate that the control strategy proposed by this paper can realize
synchronous control of shaft-less drive printing press, and also
can inhibit effectively the influences on synchronization of system
position due to change of parameters and friction during pre-
registering stage.
Keywords— pre-registering; register precision; friction; elec-
tronic virtual line shafting; sliding mode variable structure
I. INTRODUCTION
Shaft-less drive technology is widely used in printing, textile,
paper-making, printing and dyeing, steel rolling and other pro-
duction processe. The key point of the application of shaft-less
drive in production process is how to obtain good synchronous
control strategy via design so that high-precision synchroniza-
tion can be ensured in production process with nonlinearity and
disturbance.
The conventional synchronization control strategy main-
ly contains cross coupling control, relative coupling control,
master-slave control, electronic virtual line shafting control and
etc [1]. Lorenz and Meyer proposed the control method of elec-
tronic virtual line shafting in 1999 in order to compensate the
deficiencies of master-slave control, based on which further de-
velopment is made by Valenzuela and Lorenz [2]. The control
method introduces restoring torque feedback process that not in-
cluded in master-slave control to simulate physical properties of
mechanical shafting based on master-slave control. It has inher-
ent synchronization property similar to that of mechanical shaft-
ing. Therefore, it’s widely applied on actual engineering [3,4].
Synchronous coordinating running of each printing roller of
shaft-less drive printing press is mainly by independent drive ser-
vo motor. Register control will be used in case there’s chromatic
aberration, which results in that higher multi-shaft synchroniza-
tion control requirements are needed by the system [5]. Drive
motor is a complicated nonlinear object with time-varying pa-
rameters in servo system of shaft-less drive printing press. The
robustness on disturbance and parameter variation resistance of
normal PID control is not adequate. Thus it’s difficult to obtain
satisfied speed adjustment and positioning performance. There-
fore, how to find a multi-shaft synchronization method of high
performance for shaft-less drive printing press has been a topic
with very good application property.
Reference [6] and [7] apply electronic virtual line shafting
control strategy into printing press to reduce the influences of
disturbance to system, which make the system have good ro-
bust. However, the author didn’t take the influences of friction
on register precision of system at low-speed pre-register stage
of printing press into consideration. The paper proposes control
strategy of sliding mode variable structure-based electronic vir-
tual line shafting based on the adverse effects caused by friction
of pre-register process of shaft-less drive printing press and sys-
tem disturbance normally occurred during running of printing
press. Simulation and verification is carried out for four-shaft
intaglio printing system including electronic virtual line shaft-
ing on Matlab experimental platform. The experimental results
verify the effectiveness of sliding mode variable structure-based
electronic virtual line shafting synchronization strategy.
II. M
ATHEMATICAL MODEL OF SYSTEM
Synchronous coordinating running of each printing roller of
shaft-less drive printing press is mainly by independent drive
servo motor. Register control will be carried out in case of oc-
currence of chromatic aberration. All of these will result in fast,
accurate and steady control of the system with respect to position
and speed of objects. There’re many models of servo drive mo-
tor. It’s needed to emphasize disturbance torque in motor mod-
el in order to demonstrate performance of electronic virtual line
shafting-based control strategy when system parameters are vari-
able and at the time when there’s external disturbance in system.
In the paper it selects DC motor as servo drive motor.
Motor voltage and torque balance equation is:
⎧
⎪
⎪
⎨
⎪
⎪
⎩
U = RI + L
dI
dt
+ E
E = C
e
ω
T
e
− T
L
− F
f
(t)=J
dω
dt
T
e
= k
m
I
(1)
Where U is armature voltage; R is total resistance of armature
circuit; L is armature inductance; ω is turning speed of DC mo-
2013 Third International Conference on Intelligent System Design and Engineering Applications
978-0-7695-4923-1/12 $26.00 © 2012 IEEE
DOI 10.1109/ISDEA.2012.314
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