IEEE International Conference on Advances in Engineering & Technology Research (ICAETR - 2014),
August 01-02, 2014, Dr. Virendra Swarup Group of Institutions, Unnao, India
978-1-4799-6393-5/14/$31.00 ©2014 IEEE
Optimal Tuning of DC Motor Via
Simulated Annealing
Meenakshi Kishnani Shubham Pareek Dr. Rajeev Gupta
Department of ECE (UCE) Department of ECE (UCE) Department of ECE (UCE)
RTU, Kota(Rajasthan),India RTU, Kota(Rajasthan),India RTU, Kota(Rajasthan),India
Abstract— Despite the popularity, the tuning of PID controller is
a difficult task to attain by researchers and plant operators.
Several conventional methods had been proposed to optimize the
PID controller, yet, the results were highly unsatisfactory in
terms of large overshoot and big surge, thus came the
requirement for more convergent algorithm and therefore
modern heuristic approach such as Simulated Annealing is
employed to improve the capability of traditional techniques. In
this paper, a simulated annealing PID controller is designed
using IAE, ISE, ITAE , ITSE and MSE error criteria for stable
linear time invariant continuous system. The gain parameters
Kp Ki and Kd are tuned and applied to PID controller. A
comparison of system performance is observed for Ziegler-
Nicholas PID and SA-PID.
Index Terms—PID controller, Simulated Annealing, IAE, ISE,
ITAE, ITSE, MSE, DC MOTOR
I. INTRODUCTION
During the past decades, process control techniques
in the industry have made great progress. Numerous control
methods have been proposed such as: process control,
adaptive control, neural control and fuzzy control have been
studied. Still PID controller remain to be the main component
in industrial control systems included in various forms such
as: embedded controllers, programmable logic controllers and
distributed control systems. These controllers are popular
among control engineers because these are simple in structure,
reliable in operation, cost effective and robust in performance
within a wide range of operating conditions.
Van Overschee and De Moor [2] report that 80% of
PID type controllers in the industry are poorly or less
optimally tuned. They have stated that 30% of the PID loops
operate in the manual mode and 25% of PID loops actually
operate under default factory settings. Over the years many
strategies have been proposed to determine the optimum
setting of PID parameters.
PID controller can be tuned with conventional and intelligent
methods. Conventional methods such as Ziegler and
Nichols[3] and Simplex method can tune the optimal PID
parameters for only linear and stable systems. Moreover they
tend to produce big surge and large overshoot. The main
drawback of this tuning method is that it is limited merely to
certain operational zones and has an unsatisfactory design
robustness property. Intelligent methods include meta-
heuristic algorithms, fuzzy logic etc. This paper proposes to
tune the parameters of PID with one of the intelligent
algorithms named as Simulated Annealing algorithm.[4]
Simulated Annealing was introduced by Kirkpatrick
et al in 1982.it is a technique to solve combinatorial
optimization problems by minimizing the functions of many
variables.[5]using the cooling schedules to select the optimal
parameters, this method repeatedly generates, judges and
accepts/rejects the control parameters .[6]Since the simulated
annealing selects the control parameters in its own
evolutionary process and does not require a rule of thumb , has
diffused into many areas of application.
Simulated Annealing is inspired by an analogy to
annealing in solids. The algorithm simulates the cooling
process by lowering the temperature of the system(cooling
schedule) until it converges to a stable or frozen state. SA’s
major advantage over other methods is its ability to avoid
getting trapped at local minima. The algorithm employs a
random search, which not only accepts changes that decrease
objective function, but also some changes that increase it with
some probability.
PID controller is designed for the DC motor plant
with its parameters being optimized by the Simulated
Algorithm. The objective of this paper is to show that by using
SA, an optimization can be achieved .And optimized system
response for five fitness functions i.e. IAE, ISE, ITAE,ITSE
and MSE is compared in this paper.