摘要:

This paper describes the application of a recursive least squares algorithm to identify a laboratory turbogenerator system. The algorithm was initially tested in a computer simulation, which indicated that identified low-order models can represent the small-signal dynamics of a non-linear system more accurately than the corresponding linearized analytical models. This was confirmed by laboratory tests, which clearly showed the difficulty of representing the system by analytical models, and the substantial improvement obtained by identification

ISSN:0020-7179    

DOI:10.1080/00207178008961079

出版商:Taylor & Francis Group    

年代:1980

数据来源: Taylor

摘要:

This is the final paper in a series of three which have been concerned with the comprehensive evaluation of the refined instrumental variable (IV) method of recursive time-series analysis. The paper shows how the refined IV procedure can be extended in various important directions and how it can provide the basis for the synthesis of optimal generalized equation error (GEE) algorithms for a wide class of stochastic dynamic systems. The topics discussed include the estimation of parameters in continuous-time differential equation models from continuous or discrete data; the estimation of time-variable parameters in continuous or discrete-time models of dynamic systems ; the design of stochastic state reconstruction (Wiener-Kalman) filters direct from data ; the estimation of parameters in multi-input, single output (MISO) transfer function models ; the design of simple stochastic approximation (SA) implementations of the refined IV algorithms ; and the use of the recursive algorithms in self-adaptive (self tuning) control.

ISSN:0020-7179    

DOI:10.1080/00207178008961080

出版商:Taylor & Francis Group    

年代:1980

数据来源: Taylor

摘要:

A class of linear shift-invariant discrete systems satisfying a two-time-scale property is defined and a model satisfying this property is given. A pair of explicitly invertible block diagonalizing transformations are used to obtain reduced order fast and slow models analogous to the continuous singularly perturbed case. A deadbeat approximation to the fast modes results in a reduced order slow model, and a ‘ boundary layer ’ error in the original fast states. For control law design, the dual nature of these block diagonalizing transformations allows partial or total eigenvalue placement for fast and/or slow modes based on feedback designs for the reduced order slow and fast models.

ISSN:0020-7179    

DOI:10.1080/00207178008961081

出版商:Taylor & Francis Group    

年代:1980

数据来源: Taylor

摘要:

This paper presents an application of decoupling theory for designing a controller with output feedback in rapid, non-linear aeroplane manoeuvres. For simplicity in control law derivation, only momenta caused by aileron, rudder and elevator are considered, and control forces are neglected. For a class of non-linear systems, a method for designing an observer is presented. Using this approach, angle of attack and sideslip are constructed. An approximate observer is obtained by neglecting the derivatives of roll rate and aileron deflection. The non-linear controller is synthesized using estimated angle of attack and sideslip obtained from the approximate observer. Simulated responses of the closed-loop system, including the control forces, show that the neglected forces have no significant effects and the large, simultaneous lateral and longitudinal manoeuvres can be precisely performed. The control law shows only a small effect of wind gust.

ISSN:0020-7179    

DOI:10.1080/00207178008961082

出版商:Taylor & Francis Group    

年代:1980

数据来源: Taylor

摘要:

Let p(s) be a polynomial, all of whose roots lie in the left half plane. The purpose of this note is to show that when the transfer functionp(0)/p(s)tracks unit step input, the integral square error (ISE) of the response has a simple expression in terms of the Routh—Hurwitz determinants forp. This enables us to generalize a result of Hall : he pointed out that for a quadratic polynomial with fixed natural frequency, the minimum ISE is attained for a damping factor of ½. We find the corresponding result for polynomials of any degree.

ISSN:0020-7179    

DOI:10.1080/00207178008961083

出版商:Taylor & Francis Group    

年代:1980

数据来源: Taylor