Diagnostyka sinusoidalnych wahań napięcia w sieci elektroenergetycznej z wykorzystaniem wskaźnika ΔV_(10)

摘要

W artykule omówiono definicję wskaźnika ΔV_(10). Zaproponowano schemat blokowy miernika ΔV_(10) i wyznaczono jego równanie przetwarzania dla sinusoidalnej zmienności napięcia. Porównano wartości wskaźników ΔV_(10) i P_(st-). Prezentując wyniki porównań obu miar przybliżono możliwości diagnostyczne wskaźnika ΔV_(10). Odwołując się do zamieszczonych zależności ΔV_(10), P_(st), i f_m wykazano, że dla zmienności napięć występujących w sieciach elektroenergetycznych niemożliwe jest przeliczanie jednej miary do drugiej.%The ΔV_(10) index is a measure of voltage fluctuations in power grids proposed by the Japanese CRIEPI Institute [1] and used all over the Far East countries. European standards prefer P_(st), and P_(lt), indicators in voltage fluctuation measurements [11]. The ΔV_(10) and P_(st)/P_(lt) are different in terms of the characteristics of measurement signal chains [6]. Therefore the measures may be characterized by different diagnostic capabilities. This may lead to the situation where some receivers may be described as faultless while voltage fluctuations are acceptable for one measure and may be described as faulty with the voltage fluctuations being unacceptable for the other measure. On the other hand, some level of uncertainty may appear as the influence of a receiver may be classified as obnoxious with the use of one measure and not-obnoxious with the use of the other. The paper includes analytical determination of the ΔV_(10) index value dependency on the voltage fluctuation reproduced with a sinusoidal amplitude modulation (Eq. (2)). The calculations have been made for the assumed signal chain model of a ΔV_(10) index measuring instrument (Fig. 3). The values of ΔV_(10) and P_(st), indexes at a given sinusoidal voltage fluctuation have been compared (Figs. 4-6). On the basis of the obtained ΔV_(10) and P_(st), dependencies on f_m it has been assumed that for the voltage fluctuations present in power grids of unknown type and frequency it is impossible to convert one measure into the other.