Developing a hot-water drill system for the WISSARD project: 3. Instrumentation and control systems

AbstractThe WISSARD (Whillans Ice Stream Subglacial Access Research Drilling) traversable hot-water drill system was designed to create various-diameter ice boreholes to a depth of >800 m, with most major components being controllable from a single user interface. The drill control system operates four low-pressure pumps for water generation and circulation, two hot-water generation units containing a total of six diesel burner modules with integrated high-pressure pumps, three winches (one with independent level-wind motor), a four-motor linear traction drive, and a large number of analog and digital sensors to monitor system performance and cleanliness. Due to development time constraints the control system design focused on utilizing commercial off-the-shelf components, while being highly modular, easily expandable and rapidly deployable. Additional emphasis was placed on providing redundant manual operator controls and maintaining a low degree of system automation to avoid dependence on software control loops for first-season deployment. The result of this design paradigm was a control system that was taken from concept to full operation in <6 months, successfully performing in the field without insurmountable problems.

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LabVIEW based measurements and control system of a micro-ORC installation with Scroll Expander

E3S Web of Conferences ◽

10.1051/e3sconf/20187001003 ◽

2018 ◽

Vol 70 ◽

pp. 01003

Author(s):

Albrecht Eicke ◽

Sławomir Smolen

Keyword(s):

Control System ◽

Data Acquisition ◽

Thermodynamic Cycle ◽

Simple Calculation ◽

Working Fluid ◽

Thermodynamic Evaluation ◽

Control Loops ◽

Characteristic Points ◽

Matching Procedure ◽

And Control

An innovative ORC-installation with a scroll engine as expansion device has been developed and designed at the City University of Applied Sciences in Bremen. This new transportable installation has the specific capability to be connected to an alternative power source, such as solar power. Pentafluoropropane (R245fa) has been selected as the working fluid because it is suitable for the required temperature ranges and exhibits some additional advantages related to this specific application. The details of the ORC-Cycle have been presented in another paper and are not the main topic of the presented work. The core matter of this paper is the measurement and control system of the installation, which enables the thermodynamic evaluation of the obtained experimental data, some back coupling, and control tasks. The data acquisition and matching procedure, connected with the operational measurement system, identifies the aggregate and operational states of working fluid in characteristic points of the thermodynamic cycle. The algorithm for searching for the points from the table of parameters take so much time, that the control loop cannot work correctly in time. This problem was solved with the producer-consumer architecture in LabVIEW. Data acquisition and quick response in the control loops are done in the producer-while loop. To reduce the number of values, data are written only every five seconds in a queue. From this queue the consumer-while loop reads values, if the computer has enough capacity. This technique ensures that no data are lost. The matching procedure searches in the parameter file for the thermal properties and displays the cycle in a T-s diagram. Some simple calculation procedures make it possible to evaluate the thermal efficiency and other cycle parameters while operating. At the end of this sequence, the data are saved in a file. In the next step, the producer-loop is executed directly in a Field Programmable Gate Array, so that the control can be executed stand-alone and the computer is only used for visualization.

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Fuzzy Control for Variable Cooling Water Flow System

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.461.105 ◽

2012 ◽

Vol 461 ◽

pp. 105-108 ◽

Cited By ~ 1

Author(s):

Jin Ming Yang

Keyword(s):

Control System ◽

Water Flow ◽

Frequency Conversion ◽

Control Strategies ◽

Water System ◽

Cooling Water ◽

Variable Flow ◽

Control Loops ◽

Cooling Water System ◽

And Control

The variable flow cooling water system can achieve energy saving benefits just like variable primary flow chilled water system for central air conditioning system. How to design the control system with appropriate control algorithms and control strategies is particularly important. We can clarify the basic control principle of variable cooling water flow technology based on the analysis on DOF (degree of freedom) of cooling water systems, it is important for control system design. The article pointed out explicitly that the realization of variable flow technology for cooling water system must construct two control loops, one for cooling water supply temperature the other for return temperature, further more discussed control strategies for two control loops. In the end the article illustrated the synchronous frequency conversion technology for multiple cooling water pumps system to avoid overload when part of pumps put in operation

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Development of an information measuring and control system for a quadrocopter

Российский технологический журнал ◽

10.32362/2500-316x-2021-9-6-26-36 ◽

2021 ◽

Vol 9 (6) ◽

pp. 26-36

Author(s):

V. V. Sleptsov ◽

V. L. Afonin ◽

A. E. Ablaeva ◽

Ba Phuong Dinh

Keyword(s):

Control System ◽

Control Systems ◽

Block Diagram ◽

Optimal Number ◽

Control Loops ◽

Electric Drives ◽

Information Measuring ◽

Coordinate Control ◽

Functional Scheme ◽

And Control

The article deals with the issues of synthesis and analysis of information-measuring and control systems of quadrocopters. The main sensors and modules used to determine the parameters of the coordinates of quadrocopters are given. The speed-controlled electric drives used for control and the features of their choice are considered. The coordinate systems (fixed and mobile) and the kinematic scheme are given, according to which a system of differential equations is presented. The system describes the dynamics of the quadrocopter movement and takes into account the expected smooth movement of the quadrocopter with small roll and pitch angles. A functional scheme and a mathematical model of the information-measuring and control system of the quadrocopter in the form of a block diagram are developed taking into account the influence of delays in the receipt of information from the sensors of the quadrocopter parameters. A special feature of this work is to take into account the specific characteristics of the elements: adjustable electric drives (both direct and alternating current), parameter sensors (barometers, accelerometers, rangefinders, etc.). The paper studies an illustrative algorithm for the operation of the informationmeasuring and control system of the quadcopter. The type and parameters of the controllers of the quadrocopter control systems are determined. Special attention is paid to the settings for the control contours at the corresponding coordinates. The influence of the controllers of the coordinate control systems of the information-measuring and control systems of the quadrocopter on the effects of the interaction of coordinates is considered. The simulation results are presented. The optimal number of control loops for the coordinates of the information-measuring and control systems of the quadrocopter and the optimal type of settings for obtaining smooth transients (without overshoot) and for excluding the interaction of coordinates on quality indicators are determined.

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Dynamic Modeling of a Cogenerating Nuclear Gas Turbine Plant—Part II: Dynamic Behavior and Control

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.1426087 ◽

2002 ◽

Vol 124 (3) ◽

pp. 734-743 ◽

Cited By ~ 4

Author(s):

J. F. Kikstra ◽

A. H. M. Verkooijen

Keyword(s):

Control System ◽

Gas Turbine ◽

Dynamic Behavior ◽

Control Structure ◽

Control Valve ◽

Turbine Plant ◽

Control Loops ◽

Wide Range ◽

Gas Turbine Plant ◽

And Control

Using the dynamic model of the cogenerating nuclear gas turbine plant developed in Part I of this article, the dynamic behavior of this plant is analyzed and a control structure is designed. First it is determined how several design choices affect the system dynamics. Then the requirements and options for a control system design are investigated. A number of possible control valve positions in the flowsheet are tested with transients in order to make an argued choice. The model is subsequently used to determine the optimal working conditions for different heat and power demands, these are used as set-points for the control system. Then the interaction between manipulated and controlled variables is mapped and based on this information a choice for coupling them in decentralized feedback control loops is made. This control structure is then tuned and tested. It can be concluded that both heat and power demand can be followed with acceptable performance over a wide range.

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Development of a Jacobian Module for Advanced Pulp and Paper Simulation and Control

TAPPI Journal ◽

10.32964/tj8.1.4 ◽

2009 ◽

Vol 8 (1) ◽

pp. 4-11

Author(s):

MOHAMED CHBEL ◽

LUC LAPERRIÈRE

Keyword(s):

Control System ◽

Nonlinear Behavior ◽

Simulation Software ◽

Pulp And Paper ◽

Pid Controllers ◽

Tuning Parameters ◽

Pid Tuning ◽

Fixed Set ◽

And Control ◽

Operating Points

Pulp and paper processes frequently present nonlinear behavior, which means that process dynam-ics change with the operating points. These nonlinearities can challenge process control. PID controllers are the most popular controllers because they are simple and robust. However, a fixed set of PID tuning parameters is gen-erally not sufficient to optimize control of the process. Problems related to nonlinearities such as sluggish or oscilla-tory response can arise in different operating regions. Gain scheduling is a potential solution. In processes with mul-tiple control objectives, the control strategy must further evaluate loop interactions to decide on the pairing of manipulated and controlled variables that minimize the effect of such interactions and hence, optimize controller’s performance and stability. Using the CADSIM Plus™ commercial simulation software, we developed a Jacobian sim-ulation module that enables automatic bumps on the manipulated variables to calculate process gains at different operating points. These gains can be used in controller tuning. The module also enables the control system designer to evaluate loop interactions in a multivariable control system by calculating the Relative Gain Array (RGA) matrix, of which the Jacobian is an essential part.

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