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Montazeri-Gh M.,Iran University of Science and Technology | Montazeri-Gh M.,Systems Simulation and Control Laboratory | Jafari S.,Iran University of Science and Technology | Jafari S.,Systems Simulation and Control Laboratory
Journal of Propulsion and Power | Year: 2011

This paper presents the application of an evolutionary algorithm for optimization of the min-max fuel controller parameters in gas turbine engine. First, gas turbine aero engine control requirements and constraints are explained. Subsequently, an initial fuel controller based on a min-max strategy is designed and the safe bounds for transient fuel are determined in order to satisfy the engine control modes. The control gains of the initial min-max controller are then tuned by genetic algorithm, where the tuning process is formulated as an optimization problem. The time response during engine acceleration and deceleration, as well as the engine fuel consumption, are considered as the objective functions to be minimized. A computer simulation is also developed to investigate the effectiveness of the approach for a single-spool turbojet engine. The simulation results are validated by experimental data in both steady-state and transient modes to support the simulation model. The results obtained from the simulation show the ability of the approach to achieve an improved performance for engine operation as well as the engine protection against the physical limitations. Copyright © 2011 by the American Institute of Aeronautics and Astronautics, Inc.


Mohammadi E.,Iran University of Science and Technology | Mohammadi E.,Systems Simulation and Control Laboratory | Montazeri-Gh M.,Iran University of Science and Technology | Montazeri-Gh M.,Systems Simulation and Control Laboratory
Journal of Propulsion and Power | Year: 2016

Fault detection and identification of gas turbines is a crucial process for providing engine safe operation and decreasing the maintenance costs. In studies conducted in the field of global optimization-based gas turbine fault diagnosis, the genetic algorithm as the most well-known evolutionary optimization algorithm is usually employed to identify the engine health parameters. However, because of the evolutionary and stochastic nature of this algorithm, the genetic-algorithm-based diagnosis usually suffers from computational burden and reliability. To mitigate this problem, in the present work, a comparative study has been performed on the global optimization-based gas turbine fault diagnosis, and it is shown that an innovative hybrid optimization algorithm as a fault detection and identification system can significantly enhance the performance of the conventional optimization-based diagnosis systems, even in the presence of measurement noise. The results obtained indicate that the fault detection and identification system based on the hybrid invasive weed optimization/particle swarm optimization algorithm outperforms all the examined diagnosis systems (i.e., the genetic-algorithm-based, particle-swarm-optimization-based, and invasive weed-optimization-based fault detection and identification system) in terms of accuracy, reliability, and especially computational cost. The results demonstrate that the genetic-algorithm-based fault detection and identification system showed the weakest performance among all the examined diagnosis systems. Copyright © 2015 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved.


Montazeri-Gh M.,Systems Simulation and Control Laboratory | Kavianipour O.,Systems Simulation and Control Laboratory
Smart Structures and Systems | Year: 2014

In this paper, the electromagnetic damper (EMD), which is composed of a permanent-magnet rotary DC motor, a ball screw and a nut, is considered to be analyzed as a semi-active damper. The main objective pursued in the paper is to study the two degrees of freedom (DOF) model of the semi-active electromagnetic suspension system (SAEMSS) performance and energy regeneration controlled by on-off and continuous damping control strategies. The nonlinear equations of the SAEMSS must therefore be extracted. The effects of the EMD characteristics on ride comfort, handling performance and road holding for the passive electromagnetic suspension system (PEMSS) are first analyzed and damping control strategies effects on the SAEMSS performance and energy regeneration are investigated next. The results obtained from the simulation show that the SAEMSS provides better performance and more energy regeneration than the PEMSS. Moreover, the results reveal that the on-off hybrid control strategy leads to better performance in comparison with the continuous skyhook control strategy, however, the energy regeneration of the continuous skyhook control strategy is more than that of the on-off hybrid control strategy (except for on-off skyhook control strategy). Copyright © 2014 Techno-Press, Ltd.


Kavianipour O.,Systems Simulation and Control Laboratory | Montazeri-Gh M.,Systems Simulation and Control Laboratory
Proceedings of the Institution of Mechanical Engineers, Part K: Journal of Multi-body Dynamics | Year: 2014

This paper deals with the electromagnetic damper, which is composed of a permanent-magnet DC motor, a ball screw and a nut, as the passive, semi-active and active actuator in the vehicle suspension system. The main objective pursued in the paper is to study the dependences of the performance and energy regeneration of the electromagnetic suspension system on the road unevenness and the travel speed. For this purpose, the nonlinear equations of the electromagnetic damper electric circuit in the three mentioned suspension systems are developed. For the vehicle passing over the road unevenness, a seven degrees of freedom model is considered, and the simplest point-follower model is used for the tyre representation. To investigate the electromagnetic suspension system performance and energy regeneration, two types of road unevenness including a road section with a standard pure random profile and a bump modelled by cosine wave of variable height and length are applied. The simulation results demonstrate that an increase in the travel speed leads to the power spectral density increment of the road profile and in turn causes the negative effects on the performance and growth in the energy regeneration. Furthermore, when the bump height gets larger, maximum body acceleration, maximum suspension travel and energy regeneration will increase. There will be a peak on the maximum body acceleration response course when the bump length is equal to 1.1m because of exciting the sprung mass frequencies. On the maximum suspension travel and energy regeneration response course, there is a peak when the travel speed is equal to 30 km/h, which excites the unsprung mass frequencies. © IMechE 2014.


Montazeri-Gh M.,Systems Simulation and Control Laboratory | Kavianipour O.,Systems Simulation and Control Laboratory
Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science | Year: 2014

This paper deals with an electromagnetic damper, which is composed of a permanent-magnet direct current motor, a ball screw, and a nut, as an active actuator. The main objective pursued in the paper is to study the active electromagnetic suspension system (AEMSS) considering hybrid control strategy (the hybrid control strategy is a linear combination of skyhook and groundhook control strategy). For this purpose, the nonlinear equations of the electric circuit of the AEMSS should be developed. Supposing linear conditions, the coefficients determination of the hybrid control strategy is carried out in the frequency domain using the genetic algorithm in order to improve the vehicle performance and energy regeneration simultaneously. Afterwards, the achieved coefficients are used to examine the designed AEMSS in the actual conditions for an actual road profile. The simulation results demonstrate that the designed AEMSS has the desired performance while energy can be regenerated from the road excitation and transformed into electric energy. Furthermore, it has been shown that the designed AEMSS regenerates energy during the ascent and descent of a bump and consumes energy near the top of the bump. © 2013 IMechE.


Kavianipour O.,Systems Simulation and Control Laboratory | Montazeri-Gh M.,Systems Simulation and Control Laboratory | Moazamizadeh M.,Systems Simulation and Control Laboratory
Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science | Year: 2015

This paper deals with the two degrees of freedom response-type mechanism (2 DOF RTM) designed at Iran University Science and Technology. The applications of the 2 DOF RTM are to measure the longitudinal road profile and assess the vehicle suspension system. When the 2 DOF RTM is connected to a vehicle, it is able to measure the longitudinal road profile and it is capable of assessing the vehicle suspension system while it is perched upon the exciting device. The most important part of the 2 DOF RTM is its hub planned for decreasing the vehicle movement effects on the measurement. Moreover, this paper develops a novel procedure in order to convert the measured profile from the variable speed to the constant speed. To examine the 2 DOF RTM, a profile of a road is measured by the mechanism in the time-domain, and then the highly significant roughness indices such as power spectral density (PSD) of the road unevenness, international roughness index (IRI) and present serviceability index (PSI) are estimated using the measured profile. © IMechE 2014.


Montazeri-Gh M.,Systems Simulation and Control Laboratory | Kavianipour O.,Systems Simulation and Control Laboratory
Acta Mechanica | Year: 2012

In this paper, the electromagnetic damper (EMD), which is composed of a permanent-magnet DC motor, a ball screw and a nut, is considered to be analyzed as a passive damper. The main objective pursued in the paper is to determine the EMD characteristics in order to improve the vehicle performance. The effects of the EMD characteristics on ride comfort and road handling are investigated first, and then, the effect of a spring installed in series with the EMD to alter the EMD performance is observed. In order to study energy regeneration, the nonlinear equations of themodified passive electromagnetic suspension system (PEMSS) are extracted. The results of simulation show that the designed passive EMD maintains the desired performance while vibration energy from the road excitation can be regenerated and transformed into electric energy. © Springer-Verlag 2012.

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