プラント入力マッピング法を適用したディジタルモデルマッチング飛行制御系の設計

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. >

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.

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 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.

Beginning with process controls in the mid fifties, digital control systems have seldom met all the claimed advantages and in many cases have been outright failures. Airborne digital computers have just begun to appear in the commercial jet transport market after several years of experimental and military development. The success of these systems in meeting user expectations has not been overwhelming, which leads to the question: Why change from known analog flight control technology to digital? This paper examines that question by reviewing the state of the art in analog flight control system technology and evaluating this against current airline problems. A realistic means of evaluating claimed advantages for new technology is thus established. The advertised solutions of digital technology to analog problems are examined and, in some cases, debunked. However, consideration of the real problems and the capabilities of digital systems leads to the conclusion that there is a real payoff. Evidence from background studies at Boeing is offered to support this conclusion. A description of the digital flight control system electronics (FCSE) development program for the new Boeing 7×7 airplane is also provided. This program is currently in progress, and its specific objective is to assure that the real payoff is achieved for the subsequent production system.

This paper develops a comparison between two control strategies, one well-known analog control system and one digital control system, applied to a battery ZVT bi-directional charger for UPS's. The analog control system is implemented with various dedicated IC's whereas the digital control system, based on digital redesign approach, is implemented with a low cost single chip DSP controller. A prediction algorithm is used to minimize the computation time delay, and an algorithm to determine the sampling instants is developed to obtain the average values of the variables of interest, without noise caused by switching transitions. Experimental results based on a 580 W prototype have been obtained to verify the performance of these control systems.

A digital closed-loop control system with all digital phase locked loop (ADPLL) is designed and optimized, in order to improve the bias stability and transient response of the gyroscope. The nonlinear mathematical models for the closed-loop amplitude and phase control system are established. The linearization method is applied to analyze the nonlinear models. The control parameters of the drive loop are optimized. The experimental results show that the phase deviation between the demodulation reference signal of the drive loop and the sense signal is less than 0.25° in the temperature range from-40°C to 60°C, within 0.15° of the variation. At room temperature, the overshoot amount of the gyroscope control system is 4.5% with setting time of 0.12s. The bias stability is 1.45°h. Compared to the analog control scheme, the digital control system has advantages of short setting time, small overshoot, short phase locked time, large locked range, high phase precision, etc.

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

This paper discusses implications of digital flight control system design for rotorcraft and illustrates the analysis of the resulting handling qualities obtained with the Advanced Digital Optical Control System demonstrator in the context of the proposed new handling-qualities specification for rotorcraft. Topics covered are digital flight control design and analysis methods, flight testing techniques, handling-qualities evaluation results, and correlation of flight test results with analytical models and the proposed handling-qualities specification. The evaluation of the demonstrator system indicates desirable response characteristics based on equivalent damping and frequency, but undersirably large effective time delays (exceeding 240 ms in all axes). Piloted handling qualities are found to be desirable or adequate for all low, medium, and high pilot gain tasks, but handling qualities are inadequate for ultrahigh gain tasks such as slope and running landings. Correlation of these results with the proposed handling-qualities specification indicates good agreement for the bandwidth boundaries, but suggests the need for more stringent limits on allowable phase delay. Analytical models based on emulation (s-plane) techniques compare favorably with flight-extracted frequency-domain characteristics of the overall (end-to-end) system responses.

The article discusses an approach that allows you to move from a discrete model of a digital controller to its analog representation, which provides analysis and synthesis of digital systems in the continuous domain, taking into account the quantization period. In the proposed method for the control system, a transition is made from the discrete z-region to the Laplace region. This approach makes it possible to consider the quantization time as an additional parameter of the digital control system settings, evaluate the influence of the selected quantization period not only on the behavior of the set for discrete at the moments of quantization, but also in between, to evaluate the temporal characteristics of the control system at any time. The analog representation of the digital controller enables the calculation of transients using MatLAB. The article provides examples of the synthesis for a digital control system in the frequency domain based on the frequency response characteristic of an open-loop control system taking into account the quantization period. The method can be used by automation specialists to analyze and setting digital control systems

This paper focus on the digital control system for bearingless permanent magnet rotor motors. The bearingless permanent magnet synchronous motor (BPMSM) is an innovational type of motor, as bearingless motors have all advantages of magnetic bearings, they play an important role in solving difficult problems of special electric drives in life science, chemical processing industry, semiconductor manufacturing industry, foodstuff processing industry, and so on. In the paper, based on the basic working principle of BPMSM, the mathematics models of the radial forces and rotation part on BPMSM are deduced by adopting rotor magnetic field oriented control (FOC) strategy. A digital vector control system according to the demand of decoupling is designed and presented using DSP technique. An experimental platform of digital control system is developed to meet the need, The experiment results have shown that the steady suspension of the rotor is realized and the speed of the rotor can be continuously adjusted within the range of 0-3000 r/min.

A digital control system has been developed to control the frequency of an alternator operating at variable speeds. The power line frequency or a crystal controlled oscillator can be used as the reference frequency. The alternator output has a ±0.2 percent tolerance to the reference signal after the frequency control system was added. The frequency control of the alternator was accomplished by switching windings in the alternator field. The method is applicable to wind-powered alternators where the speed is variable and a constant 60 Hz output is desired.

With the development of modern automatic control technology, digital control technology has advanced technology and inherent advantages compared with traditional analog control technology. Therefore, the use of digital instrument and control system has become an inevitable trend of global nuclear power construction. Nuclear power embedded real-time operating system is an important part of digital instrument and control system in nuclear power plant. It is responsible for managing the hardware resources of the whole system and providing operation environment for application software. Its safety directly affects the safety of instrument and control system. This paper studies the application of embedded information technology in the safety of nuclear power plant, and puts forward a safety related scheme of embedded information system. The scheme fully considers the confidentiality, integrity and availability of information in the digital instrument and control system of nuclear power plant. The application results show that the scheme can meet the information security requirements of nuclear power instrument and control system, and has reference and guiding significance for the research and development of nuclear power embedded real-time operating system.

Aiming at the problem of MIG welding and considering the existing analog control wire feed system has the disadvantages of low response speed, low control accuracy and poor stability. This thesis designs a set of digital control wire feed system based on LPC2132 microprocessor and introduces the control principle of wire feed motor, CAN bus interface circuit and PID control algorithm. Under the condition of power grid voltage fluctuation and load change, we do a lot of experiments. The results show that: the wire feed change rate of designed system is very small, which not only meets the requirements of JB/T-1998.MIG/MAG arc welding standard, but also greatly improves the accuracy and stability of control system.

PurposeThe purpose of this paper is to describe the general idea, design, and implementation of control system for general aviation aircraft which reduces pilot workload.Design/methodology/approachProposed indirect flight control system framework is intended to simplify piloting, reduce pilot workload, and allow low‐end general aviation aircraft to operate under deteriorated meteorological conditions. Classical control theory is used for the design of the flight control laws. Although not inherently robust, controllers with classical control logic are made sufficiently stable using a correct and updated controller structure.FindingsDespite controversies between perception of a modern manned aerial vehicle and limitations imposed by legacy airworthiness codes it is shown that a pilot workload reducing system can be successfully implemented onboard of a low‐end general aviation aircraft.Research limitations/implicationsHi‐level control laws and optimization of handling qualities can lead to unfavourable and unpredictable forms of man‐machine interactions, e.g. pilot‐induced oscillations.Practical implicationsGeneral aviation aircraft are mostly flown by a single pilot, who could benefit from an intelligent system or “virtual copilot” assisting in or supervising the aircraft's safe operation under any conditions. Aircraft with this capability represents a next step in the evolution that might ultimately lead to trajectory‐based free‐flight concept of aircraft operations.Originality/valueThe paper introduces a safety enhanced digital flight control system on board small general aviation aircraft.