By using the gain-phase margin tester, the parameter-plane method for the nonlinear control system is extended to frequency-domain related to gain margin and phase margin. The stability and self-excited oscillation are investigated with respect to the adjustable parameters. The useful information concerning the effects of adjustable parameters can be obtained, after the describing function curves and the boundaries of constant gain margin and constant phase margin are plotted in the parameter plane. Some interesting consequences are offered by employing the practical control system of a material testing reactor. >

Analysis of gain margins and phase margins of a nonlinear reactor control system

A method for testing control system stability is presented, which is useful for finding the limit cycles of high order systems with multiple nonlinearities. The presented method is applied to the analysis of the control system of a material testing reactor, and a comparison with the method in a current literature is given.

Stability Analysis of a Nonlinear Reactor Control System

Use of Aluminum in Superconducting Cables

In this paper, the Horowitz method is first introduced for the design of nuclear reactor control systems. Then an experimental boiling water reactor (EBWR) is considered. The system can be designed to meet all the specifications, although it has twenty-eight parameters with each of-them having a quite large range of variation. For varifying the design, computer simulations are given.

Design of Nuclear Reactor Control Systems by the Horowitz Method

The design procedure for a nonlinear reactor control system is described. The control system contains two nonlinearities, separated by a linear section: a dead-band, normally used to reduce the noise excitation of the control system, and a gear backlash, which in this case is particularly important, due to the fact that the control elements are cylinders with limited effective angular range. The type of electrical motors was also defined (Slo-Syn motors, which can operate as synchronous or stepping motors). The work has been developed using analog and analytical methods in parallel, and the final control scheme (a velocity servo with stepping motors) has been throughly tested on the analog computer with noisy inputs, and theoretically studied with a describing function method extended to the case of systems with multiple nonlinearities connected by linear sections.

The Design of a Nonlinear Reactor Control System

Thedesignprocedurefora nonlinear reactorcontrolsystemisdescribed.The controlsystemcontainstwononlineariti es,separatedby a linearsection:a dead-band,normallyusedto reducethe noiseexcitationofthecontrolsystem, anda gearbacklash,whichin thiscase is particularly important,dueto the factthattheoontrolelementsarecylinderswithlimitedeffectiveangular range. Thetypeofelectrical motorswas alsodefined(Slo-Syn motors,which can operateas synchronousor stepping motors). Theworkhasbeendeveloped using analogandanalytical methodsin parallel,andthefinalcontrolscheme(a velocityservowithsteppingmotors) hasbeendhroughlytestedontheanalog computerwithnoisyinputs,andtheoreticallystudiedwitha describing functionmethodextendedto thecaseof systemswithmultiplenonlinearities connectedby linearsections.

G. Scandellari

Papers

The Design of a Nonlinear Reactor Control System

The designof a nonlinearreactorcontrolsystem