DOI: 10.18503/2311-8318-2016-3(32)-20-26
Abstract
The research objective is creation of a method of calculation of voltage fluctuations arising during operation of asynchronous motors with variable loading. Calculation results of voltage variation necessary for determining the flicker by means of which, according to [1], power quality is estimated. To achieve the goal, pilot studies were executed at the enterprise LLC "Vyatka Plywood Factory" and schedules of change of electric load of the mechanisms working with variable load were obtained. Analysis of the results of the experimental studies showed that loadings graphs solving this problem should be represented by lattice models interpolated spline - functions of the first degree. As an example, the polygons of the expectation and standard of active and reactive power variations of one of the study motor mechanisms are given. Formulas for determining the amounts of voltage characteristics in knots of the lattice model, which is also described by the spline – functions, were offered. According to the proposed method, voltage change calculation was made for one of the mechanisms. Comparison of the results of calculation of flicker were obtained using the developed method, the experiments showed that the calculation error is 8%. The technique is versatile and can be used in the design of other facilities with power-consuming equipment with variable loads.
Keywords
Voltage oscillations, abruptly variable load, flicker dose, asynchronous motor, mathematical expectation, dispersion, random process, trellised model, spline function.
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