Remote measurement calibration

The analog measurements used for state estimation generally include systematic errors introduced by the deviations in gain, zero offset, and nonlinearity of the instruments, random errors caused by the degree of precision of various instruments in the measurement streams, and installation errors due to the use of erroneous instrument ratios, transducer ratings, and scaling procedures. At present, instruments are calibrated on-site every two to three years, a procedure that is unsatisfactory, untimely, and labor intensive. A remote measurement calibration (RMC) methodology that allows elimination of installation errors and minimization of the systematic errors by frequent and remote analysis of measurements and instruments is presented. It provides the state estimator (SE) with unbiased measurements and the actual standard deviation, both of which are necessary for the SE to provide a reliable real-time database.<>