scholarly journals A Neural Approach of Multimodel Representation of Complex Processes

2008 ◽  
Vol 3 (2) ◽  
pp. 149 ◽  
Author(s):  
Nesrine Elfelly ◽  
Jeans-Yves Dieulot ◽  
Pierre Borne
Keyword(s):  
Parametric Identification ◽  
Parameters Estimation ◽  
Operating Conditions ◽  
Good Precision ◽  
Design Problems ◽  
Suggested Approach ◽  
Modeling And Control ◽  
Complex Processes ◽  
And Control

<p>The multimodel approach was recently developed to deal with the issues of complex processes modeling and control. Despite its success in different fields, it still faced with some design problems, and in particular the determination of the models and of the adequate method of validities computation. <br />In this paper, we propose a neural approach to derive different models describing the process in different operating conditions. The implementation of this approach requires two main steps. The first step consists in exciting the system with a rich (e.g. pseudo random) signal and collecting measurements. These measurements are classified by using an adequate Kohonen self-organizing neural network. The second step is a parametric identification of the base-models by using the classification results for order and parameters estimation. The suggested approach is implemented and tested with two processes and compared to the classical modeling approach. The obtained results turn out to be satisfactory and show a good precision. These also allow to draw some interpretations about the adequate validities’ calculation method based on classification results.</p>

Modeling and Control of an Ejector Based Anode Recirculation System for Fuel Cells

2005 ◽  
Author(s):  
Amey Y. Karnik ◽  
Jing Sun
Keyword(s):  
Controller Design ◽  
Design Guidelines ◽  
Operating Conditions ◽  
Feedback Controller ◽  
Modeling And Control ◽  
Recirculation Flow ◽  
Dynamic Representation ◽  
Recirculation System ◽  
Proportional Integral Controller ◽  
And Control

A control oriented analysis of an anode recirculation system that uses an ejector with a variable throat area is presented for a PEMFC system. Two control issues addressed in this paper are (a) achieving desired recirculated flow to meet humidity control requirements, and (b) regulating anode pressure to protect the polymer membrane from deformation. To meet these objectives, a static feedforward controller using the variable throat area is applied to control the recirculation flow rate, while a proportional-integral controller is designed for anode pressure regulation. A dynamic system model comprising of a nonlinear static characterization of the ejector and dynamic representation of the anode recirculation flow path is developed for controller design and evaluation. Linear analysis is used to derive design guidelines for tuning the feedback controller and to analyze the interactions between the feedback and the feedforward controllers. Our analysis shows that the system characteristics are dependent on the operating condition of throat area of ejector. To meet the control objectives for different operating conditions, a gain scheduling scheme is proposed to adjust the feedback controller parameters and the performance is evaluated through simulations. Results for two representative conditions are included.

scholarly journals Correction Procedures for Temperature and Irradiance of Photovoltaic Modules: Determination of Series Resistance and Temperature Coefficients by Means of an Indoor Solar Flash Test Device

2021 ◽  
Vol 65 (2-4) ◽  
pp. 264-270
Author(s):  
Silvia Luciani ◽  
Gianluca Coccia ◽  
Sebastiano Tomassetti ◽  
Mariano Pierantozzi ◽  
Giovanni Di Nicola
Keyword(s):  
Series Resistance ◽  
Experimental Tests ◽  
Standard Test ◽  
Operating Conditions ◽  
Test Device ◽  
Solar Simulator ◽  
Photovoltaic Modules ◽  
Current Voltage ◽  
And Control

The comparison between I-V (current-voltage) curves measured on site and I-V curves declared by the manufacturer allows to detect decrease of performance and control the degradation of photovoltaic modules and strings. On site, I-V curves are usually obtained under operating conditions (OPCs), i.e. at variable solar radiation and module temperature. OPC curves must be translated into standard test conditions (STCs), at a global irradiance of 1000 W/m2 and a module temperature of 25 °C. The correction at STC conditions allows to estimate the deviation between the power of the examined module and the maximum power declared by the manufacturer. A possible translation procedure requires two correction parameters: Rs’, the internal series resistance, and k’, the corresponding temperature coefficient. The aim of this work is to determine the correction parameters carrying out specific experimental tests as indicated by IEC 60891. A set of brand-new photovoltaic modules was experimentally characterized determining their I-V curves by means of an indoor solar flash test device based on a class A+ AM 1.5 solar simulator. Using the OPC I-V curves, obtained at several conditions of irradiance and temperature, it was possible to determine the correction parameters of the photovoltaic modules being considered.

Real-Time Modeling, Simulation, and Control System Design of a Dual Hybrid Electric Vehicle

1999 ◽  
Author(s):  
Veronika Gospodareva ◽  
William Hamel ◽  
Claudell Hatmaker ◽  
Jeffrey Hodgson ◽  
Stephen Jesse ◽  
...  
Keyword(s):  
Control System ◽  
System Design ◽  
Real Time ◽  
Electric Vehicle ◽  
Hybrid Electric Vehicle ◽  
Operating Conditions ◽  
Control System Design ◽  
Modeling And Control ◽  
Hybrid Electric ◽  
And Control

Abstract The Graduate Automotive Technology Education (GATE) Center at the University of Tennessee, Knoxville (UTK) offers courses addressing the simulation, modeling, and control system design of hybrid electric vehicles (HEV). In the Spring of 1999 such a course was conducted to support the UTK FutureCar Challenge entry for 1999. The vehicle modeled is a Dual-configuration Hybrid Electric Vehicle (DHEV) which uses a planetary power-split device similar to the Toyota Hybrid System used in the Toyota “Prius”. The goals of the course included the development of a real-time simulator that could incorporate actual vehicle control hardware in the simulator loop. This “control-hardware-in-the-loop” (CHIL) configuration was used for simulation, control system design, and troubleshooting. This approach allows the simulation of normal vehicle operating conditions as well as emergency fault handling situations in which it may not be desirable to subject the actual prototype vehicle to a given test condition. Additionally, it is possible to do a great deal of control system testing and development without an operating vehicle.

scholarly journals Hardware as for Teaching Modeling and Control

2016 ◽  
Vol 138 (06) ◽  
pp. S12-S16
Author(s):  
Joseph D. Steinmeyer ◽  
Jacob K. White
Keyword(s):  
Transfer Function ◽  
Continuous Time ◽  
Time Transfer ◽  
Design Problems ◽  
Modeling And Control ◽  
Staff Members ◽  
Introductory Classes ◽  
And Control

This article explores the introduction and use of new control classes that focus as much on modeling as on control. The paper describes several aspects of design problems with an emphasis on how to keep the process pedagogically efficient. The introductory classes in newer engineering curricula, at MIT and elsewhere, seek to empower students by avoiding highly customized devices, and instead rely on collections of easily composed and readily available sensors, actuators, and micro-controllers. The 15-week on-campus modeling and control class begins with classical material, discrete- and continuous-time transfer function modeling combined with PID and lead-lag controllers. With a combination of guidance and insights gained from constructing their artefacts, students determine a set of experiments and measurements that inform a model. Then they focus on designing and testing controllers, while answering impromptu questions from the roaming staff members.

Modeling and H2/H∞ MIMO Control of an Earthmoving Vehicle Powertrain

2002 ◽  
Vol 124 (4) ◽  
pp. 625-636 ◽  
Author(s):  
Rong Zhang ◽  
Andrew Alleyne ◽  
Eko Prasetiawan
Keyword(s):  
Power Distribution ◽  
Controller Design ◽  
Operating Conditions ◽  
Robust Controller ◽  
Modeling And Control ◽  
Linearized Model ◽  
The Time Domain ◽  
Representative System ◽  
And Control ◽  
Vehicle Powertrain

Coordination of the power distribution in a Multi-Input Multi-Output (MIMO) electro-hydraulic transmission is investigated for the case of an earthmoving vehicle powertrain. A generalized model of a representative system is presented along with the development of both H2 and H∞ MIMO controller designs. The controllers are developed based on a linearized model of the system about some nominal operating point. Multiple inputs are coordinated to control multiple load outputs simultaneously. Since typical MIMO electrohydraulic transmission systems have significant nonlinear dynamics that vary with system operating conditions, a robust controller design is paramount. The increased robustness of the H∞ controller over the H2 scheme is demonstrated qualitatively in the time domain through both disturbance rejection and trajectory tracking comparisons. A frequency domain criterion quantitatively provides quantifiable comparisons between the two methods. Hardware-in-the-Loop experiments validate the modeling and control performance on an Earthmoving Vehicle Powertrain Simulator (EVPS).

The Variable-pitch Marine Propeller

1946 ◽  
Vol 155 (1) ◽  
pp. 211-231
Author(s):  
J. Lockwood Taylor
Keyword(s):  
Sea Water ◽  
Operating Conditions ◽  
Engine Fuel ◽  
Variable Pitch ◽  
Blade Width ◽  
And Control ◽  
Propeller Performance ◽  
Ship Speed ◽  
Fixed Pitch

The author first discusses propeller performance, dealing in turn with the order of the possible gain in efficiency to be expected by adopting the variable-pitch type for different classes of ships working within a range of operating speeds. The maintenance of speed in heavy weather and with a foul hull is then considered, and reference is made to the possibility of feathering for economical cruising, to the special application of variable-pitch propellers to tugs and trawlers, and to engine fuel consumption characteristics at part load and varying propeller r.p.m. Details of manoeuvring and control are discussed, from the viewpoint of exploring the possibility of eliminating the engine reversing gear and the direct manipulation of the prime mover generally. Ship speed control from the bridge is considered, and an estimation is made of astern performance, followed by a comparison with the normal reversing of a fixed-pitch screw. Factors influencing blade design are then reviewed, e.g. type of root and size of boss, the effect of the type and number of blades on the efficiency; and reference is made to the calculation of pitch-changing moments and the possibility of balancing hydrodynamic and centrifugal components by suitable design and tilt of the blades. Various types of operating mechanism are then examined—hydraulic, electric, mechanical, and combinations of these—and mention is made of the sealing of the hub against sea water. The author also refers to the need for indicating the pitch at the control station. Lastly a comparison is made with aeronautical applications. The author shows that the range of operating conditions as affecting engine r.p.m., with a fixed pitch, is in general much less for marine screws; blade widths are much greater. In the author's conclusions it is suggested that full-scale determination of the optimum pitch setting may be valuable; consideration is also given to possible size and limitations of blade width, and to the effect of the costs involved.

Modeling and Multivariable Control of an Earthmoving Vehicle Powertrain

2001 ◽  
Author(s):  
Rong Zhang ◽  
Eko A. Prasetiawan ◽  
Andrew G. Alleyne
Keyword(s):  
Power Distribution ◽  
Controller Design ◽  
Operating Conditions ◽  
Robust Controller ◽  
Modeling And Control ◽  
Linearized Model ◽  
The Time Domain ◽  
Representative System ◽  
And Control ◽  
Vehicle Powertrain

Abstract Coordination of the power distribution in a Multi-Input Multi-Output (MIMO) electrohydraulic transmission is investigated for the case of an earthmoving vehicle powertrain. A generalized model of a representative system is presented along with the development of both H2 and H∞ MIMO controller designs. The controllers are developed based on a linearized model of the system about some nominal operating point Multiple inputs are coordinated to control multiple load outputs simultaneously. Since typical MIMO electrohydraulic transmission systems have significant nonlinear dynamics that vary with system operating conditions, a robust controller design is paramount The increased robustness of the H∞ controller over the H2 scheme is demonstrated qualitatively in the time domain through both disturbance rejection and trajectory tracking comparisons. A frequency domain criterion quantitatively provides quantifiable comparisons between the two methods. Hardware-in-the-Loop experiments validate the modeling and control performance on an Earthmoving Vehicle Powertrain Simulator (EVPS).

scholarly journals Effect of aerodynamic loads on redistribution of normal reactions of quarry dump trucks tires

2020 ◽  
Vol 174 ◽  
pp. 03018
Author(s):  
Mikhail Dadonov ◽  
Alexander Kulpin ◽  
Valery Borovtsov ◽  
Anar Zhunusbekova
Keyword(s):  
Normal Load ◽  
Operating Conditions ◽  
Dump Truck ◽  
Early Failure ◽  
Aerodynamic Loads ◽  
Truck Tires ◽  
Dump Trucks ◽  
And Control ◽  
Mine Dump

Tires of quarry dump trucks occupy one of the leading places in the item of costs for motor transport, as they are expensive product and at the same time more than half of them do not generate their resource. The causes of premature tires failure are exceeding normal load on them. In turn, the aerodynamic forces effect on the quarry dump truck as one of the influencing factors, is the dynamic redistribution of normal loads on tires and, as a result, affects temperature modes. The determination of the load on the tire under different operating conditions will increase the service life of the tires and avoid early failure. The proposed calculation method of aerodynamic loads and their influence on redistribution of normal mine dump truck tires reactions in dynamics allows to make correction to load modes and control the tires resource, which will lead to more complete use of tires resource.

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