Особенности выбора батарей конденсаторов в электрических сетях с источниками интергармоник

Abstract

Разработана методика выбора батарей конденсаторов, применяемых как в качестве компенсаторов реактивной мощности при наличии источников интергармоник, так и в составе фильтров высших гармоник и интергармоник. Получены выражения для проверки отсутствия недопустимых перегрузок батарей конденсаторов по напряжению и по току при наличии в кривой напряжения (тока), наряду с высшими гармониками, дискретного спектра интергармоник. Обоснована целесообразность упрощенного учета изменения напряжения на зажимах батарей конденсаторов фильтров высших гармоник и интергармоник за счет наличия реактора в составе фильтров. Использование предложенных подходов позволит комплексно решать ряд вопросов, связанных с выбором параметров батарей конденсаторов в электрических сетях с нелинейными нагрузками.

Development of a methodology for selecting capacitor bank parameters designed to compensate for reactive power, if there are sources of interharmonics in the electrical network. Development of a methodology for selecting the parameters of capacitor banks that are part of resonant filters of higher harmonics and interharmonics. For the research, we used the decomposition of the non-sinusoidal voltage (current) curve into the sum of the harmonic components with frequencies as multiple of the fundamental frequency - higher harmonics, and not multiple fundamental frequencies - interharmonics. Expressions are obtained for checking the absence of inadmissible overloads of capacitor banks by voltage and current in the presence of voltage (current) in the curve, along with higher harmonics, ofthe discrete spectrum of interharmonics. When selecting capacitor banks, both for reactive power compensation and for filter-compensating devices, the necessity of constructing the frequency characteristics of the input and mutual resistances of the electrical network for analyzing possible resonant phenomena is confirmed. The expediency of simplified calculation of the voltage variation at the terminals of the banks of the capacitors of the higher harmonics filters and interharmonics due to the presence of the reactor in the filters is substantiated. The use of the proposed approaches will make it possible to resolve a number of issues related to the choice of parameters of capacitor banks in networks with nonlinear loads, including: ensuring reliable operation of capacitor banks when their parameters deviate from their nominalvalues, as well as deviations in the parameters of the supply network and sources of harmonic distortion; ensuring the absence of resonant phenomena at frequencies of both higher harmonics and interharmonics.