Robust Interval Steady-State Criterion with Tunable Reference Model

When testing complex objects, it is recommended to use standardized criteria to determine the moment of the end of the transient process (TP) in the measuring circuit (MC). The criteria of the interval type (CIV) analyze the current increment of the TP signal in the MC. The paper considers only TP with first-order dynamics. It is known that the CIV has a significant restriction on its application: when the parameter of the TP model exceeds the critical constant of the criterion (CPC), we get a significant excess of the dynamic error (DE) achieved at the observation interval (OI) over the permissible level (PL) and, consequently, a false positive decision of the CIV about the beginning of the static measurement mode.The paper presents an algorithm of the robust interval criterion (RIC) – as a modification of the CIV-for determining the end point of the TP. Robustness is achieved by using a tunable implicit reference model. The controlled parameter of the RIC is the duration of the OI for the TP signal. Based on this duration, the current value of the PDA and the parameter of the reference model are calculated. The difference between the signals about the expected duration of the TP from the reference model and the moment of decision-making is information for setting the parameters of the RIC. Thus, the optimal value of OI is found.The research was carried out by the method of simulation modeling using the Monte Carlo method. The results of the research are the evaluation of the effectiveness of the robust interval criterion in the case of its application over the entire possible interval of a priori parametric uncertainty in comparison with the results of the functioning of standardized CIV. The obtained statistical results confirm the high reliability of the RIC operation and the absence of false-positive solutions in the analysis of transient signals for first-order dynamical systems.