Design of Digital Wire Feed Control System Based on LPC2132

Recently, the Plant Input Mapping (PIM) method was proposed as a digital-redesign (or an emulation) approach in digital control system design. This method guarantees stability of a redesigned digital control system for a wide range of sampling periods. In this paper the PIM method is applied to the design of a digital model-matching flight control system. In the model-matching control system design a plant must have no unstable zeros. However, unstable zeros appear for small sampling periods in a step invariance model of a continuous-time (CT) plant with the relative degree greater than two, even if the CT plant has no unstable zeros. Hence, in such a case, the direct-digital approach cannot be applied to the design of a digital model-matching control system. By contrast, the digital-redesign approach such as the Tustin's method or the PIM method is free from the problem. Simulation results for an unstable VTOL aircraft show that the proposed method gives better performance than the conventional design methods.

The DC-DC converters at the Advanced Photo Source at Argonne National Laboratory are over 15 years old. An upgrade to digital control system is being evaluated to resolve the aging and obsolescence issues. These converters supply power to electromagnets that are used to guide high energy beams. Thus a highly accurate control system is required for the DC-DC converters. This paper describes the design and evaluation of a digital control system to regulate the output current. The digital control system is proposed to replace the current analog control system thereby resolving the aging and obsolescence issues. A digital controller is first designed based on the small signal model of the converter. Experimental data of the output current is analyzed. The complete control system is then simulated and results are evaluated.

The availability of digital MSI and LSI has made digital flight control systems more cost effective than analog systems for all but the simplest systems. The organization of a digital flight control system is concerned not only with implementation of the control laws and associated logic but also with the management of the data used in these computations and the organization of the computation. The configuration taken by a digital flight control system is dominated by the integrity and data handling requirements. This paper considers the impact of these factors on the design and operation of digital flight control systems with particular emphasis on the use of fiber optics for transmission of data between lanes.

It is demonstrated that reconfigurable digital multiple model-following flight control systems incorporating fast-sampling error-actuated digital PID (proportional plus integral plus derivative) controllers can be easily designed using directly measurable input/output data. Thus, for example, it is shown in the case of the F-16 aircraft that desired flying qualities with respect to both pitch-rate and angle-of-attack response characteristics can be simultaneously achieved in the absence of sensor failures. In addition, in the case of failure of the angle-of-attack sensor, it is shown that desired flying qualities with respect to pitch-rate response characteristics and satisfactory flying qualities with respect to angle-of-attack response characteristics can still be achieved by reconfiguring the digital controller. >

Quantization error in the design of digital control systems.

This paper presents a now method of optimal digital PID feedback control for a linear multivariate system by using a, parameter optimization technique. The most difficult points for the design of optimal digital PID feedback control system by the modern control theory are : (1) the control structure of it is specified in advance, (2) unless all the state variables are fed back, the optimal control cannot be obtained by dynamic programming or the maximum principle. However, the optimal digital PID feedback gains are determined by using the parameter optimization technique in this paper. When there are some states which are not fed back in the control system, the optimal feedback gains depend on the initial states. First, the optimal solution is presented in the case where all the initial Btates are known. Next, it is extended to the case where the initial states are random variables and their statistical properties are known,

In the design of digital control systems, the time delay due to computation time of a processor cannot be often neglected. In this paper, we consider the problem of synthesizing a type-1 optimal digital servosystem taking account of controller delay of one sampling period.It is first shown that the optimal digital servo problem in which a quadratic criterion function is defined for a given continuous-time plant can be reasonably reformulated to a discrete optimal regulator problem. To assure the solvability of this problem, some conditions for the preservation of stabilizability and detectability of the plant under sampling are given. In the discrete optimal regulator problem considered here, not only control input but also the initial state of the servocompensator are referred as free design parameters. The obtained optimal digital control law contains a feedforward term of reference signal in addition to a feedback term. It is also shown that the optimal control law has a function of estimating the state variables at the following sampling period in order to recover the controller delay.

This paper considers the application of error analysis algorithms for the linear quadratic gaussian problem to the design of digital control systems for a simple model of a helicopter in hover. Particularly, we investigate the influence on the performance of modelling errors in the stability derivatives and correlation time of the wind gust model. The algorithms presented enable the determination of performance loss in the case of reduced order models. As an example of this possibility we will consider the case when colored system noise is misindentified as a gaussian white noise. The simulated results, for a helicopter in hover, given in the paper indicate that the extra effort expended in parameter identification may not be justified as the optimal trajectory and final performance is practically insensitive to errors in most of the model parameters.

SummaryThe synthesis of discrete-time tracking systems incorporating Lur’e plants with multiple non-linearities is illustrated by the design of a fast-sampling digital controller and associated transducers for the automatic control of the longitudinal motions of the CH-47 helicopter with both gang-collective and differential-collective non-linearities. In particular, it is demonstrated that non-interacting control of the vertical velocity and pitch attitude of the helicopter is readily achievable for large classes of non-linear actuator characteristics such as ‘deadzone’ provided that the controller and transducer parameters are chosen so as to ensure that state-bounded absolutely stable tracking occurs.

The insertion of communication networks in closed-loop of digital control systems makes the system synthesis and analysis complex. In this paper, we consider the combination of classical reliability, risk and safety evaluation with typical control system through digital networked control systems. The main purpose is to study the influence of transmission delays and packet dropouts on the reliability of digital networked control systems by using a modified statistical method-Monte Carlo simulation. The behaviors of two types of fault are modelled by different statistical distribution. The control strategies we apply for digital control systems are Proportion Integration Differentiation control strategies, generated by Genetic Algorithm. In terms of a realistic system model, we evaluate and compare the influences on the reliability of digital networked control systems with different control strategies from quantitative aspect. Numerical examples are presented to illustrate the effectiveness and correctness of the approach.

This paper has introduced a design of digital speed control system of permanent magnet brushless DC motor based on MCS-80C196KC.The system use Direct Back-EMF to detect rotor position, and combined with three-start technology to expand the speed control range. Application of Double Closed Loop PID control method to overcome the limitations of conventional control methods, which provide a new way for the design and manufacture of motor and the debug of control systems.

Simulation modeling of nuclear steam generator water level process — a case study

In digital control system (DCS) design, independent hardware logic circuit design is usually used to deal with common causes failures of software. Due to the distinct difference between the design criteria of electrical design diagram and logic schematic diagram, the hardware logic verification should be carried out in the form of translation simulation. In this paper, the modeling criteria of DCS hardware logic simulation are summarized. The modeling criteria take into account both the standard engineering hardware logic drawing specifications and the characteristics of Simulink platform, and the DCS hardware logic electrical design information is translated to the Simulink platform for automatic redrawing according to specific criteria. A complete hardware logic simulation system was established based on the modeling criteria, and the application was verified in HPR 1000 Zhangzhou nuclear power plant project.KeywordsModeling translationHardware logicSimulation

This paper presents t he design and implementation (using a TI 9900 microcomputer system) of digital control systems for an environmental chamber utilized in the study of plant growth. Two control systems were implemented - one to control dry-bulb temperature and the o ther to control the carbon dioxide content in the chamber atmosphere. In addition, real-time data acquisition, automatic restart following power outages, and an interactive operating system have been achieved. The CO system is a closed-loop modified proportional control system. The closed-loop temperature control system uti1 ized a proportional-plusintegral-plus-de rivative digital controller. The environmental chamber is presently used in research by the USDA at Auburn University. 2

International Journal of Adaptive Control and Signal ProcessingVolume 12, Issue 7 p. 600-602 Book ReviewFree Access Digital Control Systems, P. N. Paraskevopoulos, Prentice Hall Inc., Hemel Hempstead, Herts, England, U.K., 1996, ISBN 0-13-341876-6, xv + 383pp., Price: £25.95 T. Chen, T. Chen Department of Electrical and Computer Engineering, The University of Alberta, Edmonton, Alberta, Canada T6G 2G7Search for more papers by this author T. Chen, T. Chen Department of Electrical and Computer Engineering, The University of Alberta, Edmonton, Alberta, Canada T6G 2G7Search for more papers by this author First published: 18 December 1998 https://doi.org/10.1002/(SICI)1099-1115(199811)12:7<600::AID-ACS509>3.0.CO;2-CAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. References 1 Franklin, G. F., J. D., Powell and M. L. Workman, Digital Control of Dynamic Systems, Addison-Wesley, Reading, MA, 1990. 2 Aström, K. J. and B., Wittenmark, Computer Control Systems, Prentice-Hall, Englewood Cliffs; NJ, 1984. 3 Phillips, C. L. and H. T., Nagal, Digital Control System Analysis and Design, Prentice-Hall, Englewood Cliffs, NJ, 1990. 4 Ogata, K., Discrete-Time Control Systems, Prentice-Hall, Englewood Cliffs, NJ, 1987. 5 Chen, T. and B. A., Francis, Optimal Sampled-Data Control Systems, Springer, Berlin, 1995. Volume12, Issue7November 1998Pages 600-602 ReferencesRelatedInformation