Patent RU-2506623-C1 (RU)
Title: Method of searching for faulty unit in discrete dynamic system
Inventor: KISELEV VLADISLAV VALER EVICH
IPC: G05B23/02
Filed: 2012-10-08
Granted: 2014-02-10
Abstract: FIELD: physics; control. 
     SUBSTANCE: field of application can be monitoring and diagnosis of automatic control systems and components thereof. The reaction of an operable time-discrete system is recorded for discrete diagnosis cycles with a discrete constant step on an observation interval at control points, and integral estimates of output signals of the discrete system are determined, for which at the moment of transmitting a test or operating signal to the input of the discrete system with nominal characteristics, discrete integration of signals of the control system is simultaneously started with a step at each control point with a weight function equal to the arithmetic average value of moduli of derivatives of its signals at the control points, where averaging is carried out based on the number of control points. To this end, system signals are transmitted to first inputs of multiplier units, the average arithmetic value of moduli of time derivatives of signals are transmitted to the second inputs of the multiplier units, output signals of the multiplier units are transmitted to the inputs of the units for discrete integration with a step, discrete integration is completed at a moment in time, estimates of output signals resulting from integration are recorded, the number of considered individual defects of units is determined, integral estimates of model signals for each control point obtained as a result of test deviations for individual defects of units are determined, for which the test deviation of the parameter of the discrete transfer function is successively input into each unit of the discrete dynamic system and integral estimates of output signals of systems with test deviations for the test signal or operating signal are found, output signal estimates obtained as a result of discrete integration for each control point and each test deviation are recorded, deviations of integral estimates of signals of the discrete model obtained as a result of test deviations of parameters of different structural units are determined, standardised values of deviations of integral estimates of signals of the discrete model obtained as a result of test deviations for individual defects are determined, an analogue test signal or operating signal is transmitted to the input of the controlled system at the beginning of control, integral estimates of signals of the controlled discrete system for control points are determined, the obtained values are recorded, the deviations of integral estimates of signals of the controlled discrete system for control points from nominal values are determined, the standardised values of deviations of integral estimates of signals of the controlled discrete system are determined, diagnostic features are determined, the serial number of the defective unit is determined from the minimum value of the diagnostic feature. 
     EFFECT: broader functional capabilities of the method by applying operating diagnosis (without using test input), higher noise-immunity of the method of diagnosing discrete automatic control systems by improving distinguishability of defects and lower hardware costs on calculating the weight function. 
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