摘要:

A novel crosscorrelation technique of obtaining dynamic measurements on the systems controlling a 2-axis stable platform carrying a large antenna is reported. Rotation of the antenna causes platform control parameters to be periodically time varying, the periodicity being comparable with control-system time constants. A theoretical analysis of the technique is reported that shows that measurements are realistic, uncorrupted and suitable for determining the nature of compensating device such as a digital filter. Results from measurements on the system, together with results from offline and online simulations, are presented.

DOI:10.1049/piee.1977.0177

出版商:IEE    

年代:1977

数据来源: IET

摘要:

A design procedure is described for constant linear multivariable systems that must minimise a finite time quadratic cost function and achieve a fixed terminal state. This is the first presentation of a general solution to this problem in the complex-frequency domain. To achieve this solution a gradient function is calculated and the theory of projection operators is employed. A technique is described by which the optimal open loop control can be implemented in feedback system form.

DOI:10.1049/piee.1977.0178

出版商:IEE    

年代:1977

数据来源: IET

摘要:

A design method is presented for linear multivariable systems with cascade controllers. The method is restricted to general systems with two input and two output variables and is applied in the frequency domain using dual-locus plots. Loci are formed that relate directly to the closed loop characteristic polynomial of the system and conditions are derived from an unambiguous indication of stability. The loci are chosen so that the effects of controller elements can be readily assessed, and this leads to an iterative procedure for controller design. The method has been applied to a position control system for a 2-axis gyroscope and is shown to yield high performance although retaining simplicity in the controller functions.

DOI:10.1049/piee.1977.0179

出版商:IEE    

年代:1977

数据来源: IET

摘要:

A regulator-design algorithm is described in which a systematic numerical technique is used to predetermine the performance criterionJ= ∫0∞(xtQx+u2)dt. The constraints imposed on the system response by the design specification are associated with the movement of the eigenvalue locations to give actual values for the elements ofQ. The algorithm described here, for the linear single-input system, is based on the sensitivity of the elements ofQto shifts in the eigenvalue locations to produce a performance criterion for improved system stability. A practical example of the method, applied to the voltage control of a synchronous machine, is included.

DOI:10.1049/piee.1977.0180

出版商:IEE    

年代:1977

数据来源: IET

摘要:

The problem of designing decentralised regulators for the load-frequency control of interconnected energy systems is studied. Starting with stochastic state and output models, a solution of the decentralised-control problem is presented by making use of modelling-error-compensation technique along with bias-estimation procedure. Some numerical results based on computer simulation of a 2-area power system are also presented.

DOI:10.1049/piee.1977.0181

出版商:IEE    

年代:1977

数据来源: IET

摘要:

A method is described for the design of optimal linear servomechanisms. The system to be controlled is assumed to be linear, time invariant and multivariable. The cost function to be minimised is quadratic and is measured over an infinite time interval. Expressions are given to enable the optimal controllers for both open-loop and closed-loop systems to be calculated. A result is obtained that allows the cost function weighting terms to be related to the optimal-compensated system pole positions, and hence to the system transient response. The relationship can be used when choosing the weighting constants. The design procedure is illustrated in the design of a controller for a strip processing line for which the tension in the strip and the speed of the drives is to be controlled. A new method of spectral factorisation is also introduced. This can only be used on a restricted-class matrices having a degree of symmetry; however, it is much easier to use than previous methods.

DOI:10.1049/piee.1977.0182

出版商:IEE    

年代:1977

数据来源: IET

摘要:

The time delay to the firing of a triggered vacuum gap (t.v.g.) containing barium titanate in the trigger gap is investigated as a function of the main gap voltage, main gap length, trigger pulse duration, trigger current and trigger voltage. The time delay decreases steadily with increasing trigger current and trigger voltage until it reaches saturation. The effect of varying the main gap length and voltage on the time delay is not strong. Before ‘conditioning’ the t.v.g. two groups of time delays, long (>100μs) and short (<10μs), are simultaneously observed when a large number of trials are conducted. After conditioning, only the group of short time delays are present. This is attributed to the marked reduction of the resistance of the trigger gap across the surface of the solid dielectric resulting directly from the conditioning effect.

DOI:10.1049/piee.1977.0183

出版商:IEE    

年代:1977

数据来源: IET

摘要:

A method for the accurate calibration of a reference capacitor is presented that relies on instruments often available in educational and industrial laboratories. These are a reference resistor, an inductive voltage divider and a multiple period counter. While the principles are elementary, precautions must be taken if an uncertainty of 100 p.p.m. or less is to be achieved. Sources of error are therefore analysed. It is shown how errors can be reduced by a system of screening and by corrections derived from simple preliminary measurements.

DOI:10.1049/piee.1977.0184

出版商:IEE    

年代:1977

数据来源: IET