INVESTIGATION OF THE AMPLITUDE STABILITY RELATION OF A MATHEMATICAL MODEL OF A CENTRIFUGAL PUMP OF A PUMPING UNIT AS AN OBJECT OF CONTROL WITH A DEGREE OF GAS PRESSURE

Abstract

Using the experimental data obtained intheprocesso fchange inthetime of the degree of increase in gas pressure, as well as the performance of the centrifugal supercharger of the gas pumping unit, . Digitization of graphs of change of degree of increase of pressure of gas, and also productivity of the centrifugal supercharger of gas-pumping unitis made with the help of software Graph2Digit. The digitization wasper formed with a sampling period of 0.3 s. The number of values forth edegree of increase of gaspressure, as well as the performance of the centrifugal pump gas pumping unitis 581 each.
 The experimental data are divide dinto ranges (1 - 811 sec - 818 sec; 2 - 818 sec - 825 sec; 3 - 811 sec - 831 sec; 4 - 825 sec - 831 sec; 5 - 827 pp. - 832 pp .; 6 - 829 pp. - 831 pp.). In the course of the study, the mathematical expectation for each of the intervals, as well as the spectral density equation for the degree of gas pressure increase and the spectral density equation for the performance of the centrifugal supercharger of the gaspumping unit, were determined at appropriate intervals.
 Using there lation between the spectral densitiesand the fact function of the Matlab software product, which factorizes fractional-rational expression, the gear function saredetermine date achinter valand the stability stocks are determine dusing the Nyquist criterion.
 The plot of the stability reserve of the centrifugal supercharger of the gas pumping unit as an object of control from the mathematical expectation, which is obtained on the basis of the spectral density ratios, is made. This dependency is approximated by the CurveExpert Professional software to select the optimalma them at icalmodel.
 From the set of results, the one with the high estcorrelation coefficient and the small eststandard error isselected.