A cascaded sliding mode control for magnetic levitation systems. A disturbance observer-based sliding mode controller is designed for the electrical loop while a state and disturbance observer-based sliding mode controller is designed for the electromechanical loop. The overall stability of the system is rigorously established. The performance of the proposed scheme is compared with a conventional linear quadratic regulator combined with a proportional-integral controller by simulation as well as experimentation on a magnetic levitation setup in a laboratory
27. 0 5 10 15 20 25
0
0.2
0.4
0.6
time in sec
x2
(e)
Figure: Case I. Simulation result of LQR control design
Case: II
0 5 10 15 20 25
0.8
1
1.2
1.4
·10−2
time in sec
x1andr
(a)
0 5 10 15 20 25
−0.5
0
0.5
1
1.5
·10−3
time in sec
x1-r
(b)
28. 0 5 10 15 20 25
14
16
18
20
22
24
time in sec
voltage(V)
(c)
0 5 10 15 20 25
0
1
2
3
time in sec
current(A)
(d)
0 5 10 15 20 25
0
0.2
0.4
0.6
time in sec
x2
(e)
Figure: Case II. Simulation result of LQR control design
34. 0 5 10 15 20 25
−0.1
−5 · 10−2
0
5 · 10−2
0.1
time in sec
x2
(e)
Figure: Case I. Experimental result of LQR control design
Case: II
0 5 10 15 20 25
0.8
1
1.2
1.4
·10−2
time in sec
x1andr
(a)
0 5 10 15 20 25
0
2
4
·10−3
time in sec
x1−r
(b)
35. 0 5 10 15 20 25
0
10
20
time in sec
voltage(V)
(c)
0 5 10 15 20 25
0
0.5
1
1.5
2
time in sec
current(A)
(d)
0 5 10 15 20 25
−0.1
0
0.1
time in sec
x2
(e)
Figure: Case II. Experimental result of LQR control design
42. Table: Specification for LSM
Criteria Design Specification
Class of motor Linear Synchronous
Primary 3∅ winding embedded in track
Secondary 4 disc magnet array
Drive Current –
Drive Frequency –
Table: Specification for Train Track
Criteria Design Specification
Topology Linear Track
Material Acrylic, Glue
Dimension 45 mm ×1000 mm × 500 mm
Train car weight 559 gm
56. College Of
Engineering,
Pune
Introduction
Mathematical
Modeling
State
Feedback
Control
SMC
IDO
LQR Design
IDC
Simulation
Result
Exprimental
Result
MAGLEV
Train
Electromagnetic
Levitation
System
Conclusion and Future work
The Different control techniques are implemented for the
precise position control of a magnetic levitation system
which is inherently nonlinear in nature. IDO is designed to
estimate states and disturbances occurred in system. IDC
is implemented for current loop to estimate the lumped
uncertainty. All control techniques are compared with
LQR techniques and observed that proposed control
technique gives significantly improved results.
The Low cost and simple electromagnetic levitation
system using analog circuit is successful developed.
The development of remaining MAGLEV train work is
carried out for next year.