Modeling and Control of an Electro-Hydraulic Poppet Valve

2004 ◽  
Author(s):  
Patrick Opdenbosch ◽  
Nader Sadegh ◽  
Wayne J. Book
Keyword(s):  
Mathematical Model ◽  
Control Valve ◽  
Model Parameters ◽  
Hydraulic Control ◽  
Nonlinear Mathematical Model ◽  
Modeling And Control ◽  
Poppet Valve ◽  
Control Scheme ◽  
Experimental Approaches ◽  
And Control

This paper explores the dynamic modeling of a novel two stage bidirectional poppet valve and proposes a control scheme that uses a Nodal Link Perceptron Network (NLPN). The dynamic nonlinear mathematical model of this Electro-Hydraulic Control Valve (EHCV) is based on the analysis of the interactions among its mechanical, hydraulic, and electromagnetic subsystems. A discussion on experimental approaches to determine the model parameters is included along with model validation results. Finally, the control scheme is developed by proposing that the states of the EHCV follow a set of desired states, which are calculated based upon the desired valve flow conductance coefficient KV. A simulation is presented at the end to verify the proposed control scheme.

An Innovation-Based Methodology for HVAC System Fault Detection

1985 ◽  
Vol 107 (4) ◽  
pp. 284-289 ◽  
Author(s):  
P. B. Usoro ◽  
I. C. Schick ◽  
S. Negahdaripour
Keyword(s):  
Mathematical Model ◽  
Control Systems ◽  
Energy Management ◽  
Air Conditioning ◽  
Energy Use ◽  
Hvac System ◽  
Test Results ◽  
Nonlinear Mathematical Model ◽  
Control Scheme ◽  
And Control

Although Energy Management and Control Systems (EMCS) have since the early 1970’s contributed significantly to the reduction (20-40 percent) of energy use in buildings without sacrificing occupants’ comfort, their full capabilities have not been completely realized. This is in part due to their inability to quickly detect and compensate for failures in the Heating, Ventilation and Air Conditioning (HVAC) system. In fact, no matter how good the control scheme for the HVAC system might be, the presence of undetected faults can completely offset any expected savings. This paper presents a methodology for detecting faults in an HVAC system using a nonlinear mathematical model and an extended Kalman filter. The technique was implemented in a computer program and successfully used to detect “planted” faults in simulations of the air handler unit of an HVAC system. Test results are presented to demonstrate the effectiveness of the methodology.

Design and Simulation on Multi-Digit Numerical Control Valve in Water Hydraulics

2011 ◽  
Vol 422 ◽  
pp. 257-261
Author(s):  
Zeng Meng Zhang ◽  
Yong Jun Gong
Keyword(s):  
Control Valve ◽  
Poor Performance ◽  
Numerical Control ◽  
Hydraulic Control ◽  
Control Performance ◽  
Poppet Valve ◽  
Water Hydraulics ◽  
Water Hydraulic ◽  
The Stability ◽  
And Control

Due to the problems about Lubrication and sealing in water hydraulics, the poor performance, large leakage, extreme requirements of processing, high cost and poor anti-pollution properties exist in water hydraulic servo or proportional valves of spool structure and analogue control. A better seal is provided by the structure of the poppet valve comparing to the spool valve, however, poorer linearity and control accuracy accompanying inevitably. Aiming at improving the control performance of poppet valve, the design of the multi-digit numerical control valve is analyzed in this paper. The novel design using ball seat valves for digital bits is proposed to ensure enough seal ability and lower the cost. The simulation model of the multi-digit numerical control valve is built in AMESim software and the results show high linearity in flow control. However, large overshoot and oscillation encounter during the switching of the digits. Especially the switching process of the high digital bits requires to be regulated to reduce the large overshooting. The adjustment of the spring in the sensitive chamber of the bit valve can decrease the overshoot and improve the stability. These above contribute to the improvement of the control performance of water hydraulic control valves and applications of water hydraulics in the industry.

NEURAL MODELING AND CONTROL OF DYNAMIC SYSTEMS WITH HYSTERESIS

2007 ◽  
Vol 31 (1) ◽  
pp. 127-141
Author(s):  
Yonghong Tan ◽  
Xinlong Zhao
Keyword(s):  
Dynamic Systems ◽  
Control Strategy ◽  
Neural Modeling ◽  
Modeling And Control ◽  
Control Scheme ◽  
The Neural Networks ◽  
Adaptive Control Strategy ◽  
Set Up ◽  
Modeling Strategy ◽  
And Control

A hysteretic operator is proposed to set up an expanded input space so as to transform the multi-valued mapping of hysteresis to a one-to-one mapping so that the neural networks can be applied to model of the behavior of hysteresis. Based on the proposed neural modeling strategy for hysteresis, a pseudo control scheme is developed to handle the control of nonlinear dynamic systems with hysteresis. A neural estimator is constructed to predict the system residual so that it avoids constructing the inverse model of hysteresis. Thus, the control strategy can be used for the case where the output of hysteresis is unmeasurable directly. Then, the corresponding adaptive control strategy is presented. The application of the novel modeling approach to hysteresis in a piezoelectric actuator is illustrated. Then a numerical example of using the proposed control strategy for a nonlinear system with hysteresis is presented.

Modeling and Control of a Complex Interacting Process

2011 ◽  
Vol 403-408 ◽  
pp. 3758-3762
Author(s):  
Subhajit Patra ◽  
Prabirkumar Saha
Keyword(s):  
Storage System ◽  
Linear Quadratic Regulator ◽  
Model Parameters ◽  
Linear Quadratic ◽  
Modeling And Control ◽  
Dynamic Matrix ◽  
Liquid Storage ◽  
Efficient Control ◽  
And Control

In this paper, two efficient control algorithms are discussed viz., Linear Quadratic Regulator (LQR) and Dynamic Matrix Controller (DMC) and their applicability has been demonstrated through case study with a complex interacting process viz., a laboratory based four tank liquid storage system. The process has Two Input Two Output (TITO) structure and is available for experimental study. A mathematical model of the process has been developed using first principles. Model parameters have been estimated through the experimentation results. The performance of the controllers (LQR and DMC) has been compared to that of industrially more accepted PID controller.

scholarly journals Dynamic Modeling and Control of a Coupled Reforming/Combustor System for the Production of H2 via Hydrocarbon-Based Fuels

Processes ◽  
2020 ◽  
Vol 8 (10) ◽  
pp. 1243
Author(s):  
Dimitris Ipsakis ◽  
Theodoros Damartzis ◽  
Simira Papadopoulou ◽  
Spyros Voutetakis
Keyword(s):  
H2 Production ◽  
Saturated Hydrocarbons ◽  
Modeling And Control ◽  
Start Up ◽  
Control Scheme ◽  
Reactor Temperature ◽  
Zero Offset ◽  
And Control ◽  
Water Gas ◽  
Reforming Reactions

The present work aims to provide insights into the dynamic operation of a coupled reformer/combustion unit that can utilize a variety of saturated hydrocarbons (HCs) with 1–4 C atoms towards H2 production (along with CO2). Within this concept, a preselected HC-based feedstock enters a steam reforming reactor for the production of H2 via a series of catalytic reactions, whereas a sequential postprocessing unit (water gas shift reactor) is then utilized to increase H2 purity and minimize CO. The core unit of the overall system is the combustor that is coupled with the reformer reactor and continuously provides heat (a) for sustaining the prevailing endothermic reforming reactions and (b) for the process feed streams. The dynamic model as it is initially developed, consists of ordinary differential equations that capture the main physicochemical phenomena taking place at each subsystem (energy and mass balances) and is compared against available thermodynamic data (temperature and concentration). Further on, a distributed control scheme based on PID (Proportional–Integral–Derivative) controllers (each one tuned via Ziegler–Nichols/Z-N methodology) is applied and a set of case studies is formulated. The aim of the control scheme is to maintain the selected process-controlled variables within their predefined set-points, despite the emergence of sudden disturbances. It was revealed that the accurately tuned controllers lead to (a) a quick start-up operation, (b) minimum overshoot (especially regarding the sensitive reactor temperature), (c) zero offset from the desired operating set-points, and (d) quick settling during disturbance emergence.

Modeling and Control of a Rotary Crane

1985 ◽  
Vol 107 (3) ◽  
pp. 200-206 ◽  
Author(s):  
Y. Sakawa ◽  
A. Nakazumi
Keyword(s):  
Feedback Control ◽  
Equilibrium State ◽  
Open Loop ◽  
The State ◽  
Control Input ◽  
Loop Control ◽  
Modeling And Control ◽  
Control Scheme ◽  
Rotary Crane ◽  
And Control

In this paper we first derive a dynamical model for the control of a rotary crane, which makes three kinds of motion (rotation, load hoisting, and boom hoisting) simultaneously. The goal is to transfer a load to a desired place in such a way that at the end of transfer the swing of the load decays as quickly as possible. We first apply an open-loop control input to the system such that the state of the system can be transferred to a neighborhood of the equilibrium state. Then we apply a feedback control signal so that the state of the system approaches the equilibrium state as quickly as possible. The results of computer simulation prove that the open-loop plus feedback control scheme works well.

Physical Modeling and Control of a Multi-Cylinder HCCI Engine

2009 ◽  
Author(s):  
Nikhil Ravi ◽  
Matthew J. Roelle ◽  
Hsien-Hsin Liao ◽  
Adam F. Jungkunz ◽  
Chen-Fang Chang ◽  
...  
Keyword(s):  
Direct Injection ◽  
Work Output ◽  
Compression Ignition ◽  
Piston Engine ◽  
Modeling And Control ◽  
Hcci Engine ◽  
Operating Region ◽  
Control Scheme ◽  
And Control ◽  
Wide Operating

Homogeneous charge compression ignition (HCCI) is one of the most promising piston-engine concepts for the future, providing significantly improved efficiency and emissions characteristics relative to current technologies. This paper presents a framework for controlling a multi-cylinder HCCI engine with exhaust recompression and direct injection of fuel into the cylinder. A physical model is used to describe the HCCI process, with the model states being closely linked to the thermodynamic state of the cylinder constituents. Separability between the effects of the control inputs on the desired outputs provides an opportunity to develop a simple linear control scheme, where the fuel is used to control the work output and the valve timings are used to control the phasing of combustion. Experimental results show good tracking of both the work output and combustion phasing over a wide operating region. In addition, the controller is able to balance out differences between cylinders, and reduce the cycle-to-cycle variability of combustion.

Polymer Film Production: Modeling and Control of the Forward Draw

2009 ◽  
Vol 132 (1) ◽  
Author(s):  
C. R. MacLaine ◽  
P. Acarnley ◽  
J. Shanahan ◽  
P. Mousalli ◽  
M. Deighton
Keyword(s):  
Polymer Film ◽  
Industrial Processes ◽  
Production Plant ◽  
Film Production ◽  
Modeling And Control ◽  
Feed Forward Control ◽  
Control Scheme ◽  
Production Modeling ◽  
And Control ◽  
Physical Phenomena

Many industrial processes involve the transportation of a continuous web of material over a series of rollers to obtain a finished product. The manufacture of polymer film is one such web transport process, which utilizes a series of rotating elements that act to manipulate the film. This paper develops a dynamic mathematical model of the “forward draw” in a polymer film production process. The model is capable of being implemented in real-time for control purposes, yet includes significant physical phenomena such as material damping. Experimental results from a pilot production plant are used to validate the model under steady-state and transient conditions. The model is then used as a basis for a feed-forward control scheme, which reduces speed variations in the forward draw by a factor of 8 and therefore improves considerably the film quality.

Nonlinear Modeling and Control of Overhead Crane Load Sway

1988 ◽  
Vol 110 (3) ◽  
pp. 266-271 ◽  
Author(s):  
Kamal A. F. Moustafa ◽  
A. M. Ebeid
Keyword(s):  
Control System ◽  
Feedback Control ◽  
Digital Computer ◽  
Nonlinear Modeling ◽  
Overhead Crane ◽  
Nonlinear Dynamical ◽  
Modeling And Control ◽  
Control Scheme ◽  
Rate Of Decay ◽  
And Control

In this paper, we derive a nonlinear dynamical model for an overhead crane. The model takes into account simultaneous travel and transverse motions of the crane. The aim is to transport an object along a specified transport route in such a way that the swing angles are suppressed as quickly as possible. We develop an antiswing control system which adopts a feedback control to specify the crane speed at every moment. The gain matrix is chosen such that a desired rate of decay of the swing angles is obtained. The model and control scheme are simulated on a digital computer and the results prove that the feedback control works well.

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