Wyniki wyszukiwania - BazTech

1

Assessing system impedance based on data regrouping

Xu Shuangting, Xiao Xianyong, Wang Yang, Wu Jun

Metrology and Measurement Systems

|

2021

|

Vol. 28, nr 1

191--208

EN

In recent years, assessing supply system impedance has become crucial due to the concerns on power quality and the proliferation of distributed generators. In this paper, a novel method is shown for passive measurement of system impedances using the gapless waveform data collected by a portable power quality monitoring device. This method improves the overall measurement accuracy through data regrouping. Compared with the traditional methods that use the consecutive measurement data directly, the proposed method regroups the data to find better candidates with less flotation on the system side. Simulation studies and extensive field tests have been conducted to verify the effectiveness of the proposed method. The results indicate that the proposed method can serve as a useful tool for impedance measurement tasks performed by utility companies.

2

Voltage stability estimation of receiving node using approximate model

Brusilowicz B, Szafran J.

Present Problems of Power System Control

|

2014

|

Nr 5

44—54

EN

The paper presents approximate model for determining the voltage stability margin. In the first part, Thevenin model and equations describing this model e.g. stability limit are presented. Influence of load and system impedance changes on variations of node voltage are shown. Second part consist description of approximate model determination methods. For the analysis, the 14-bus IEEE model have been chosen. Basing on this model the impact of configuration changes on the Thevenin parameters of considered receiving nodes have been analysed. At the end, the possibilities of use of approximate model for determining the voltage stability margin are described.

3

Non-linear load model for the local stability studies

Solak K., Brusiłowicz B., Szafran J.

Przegląd Elektrotechniczny

|

2013

|

R. 89, nr 10

26-30

EN

This paper presents the non-linear load model which can be used to study the local stability of the power system node. There have been shown the initial assumptions and implemented functions. Model based on Thevenin theory allows to present set part of the power system as voltage source and series impedance. This approach lets perform simple analysis of the influence of the voltage regulation on the local stability margin. In addition prepared program can also plot PU, QU, SU and load curves for the graphical representation of the node condition.

PL

Artykuł prezentuje nieliniowy model obciążenia wykorzystany do badania stabilności lokalnej węzłów systemu elektroenergetycznego. Przedstawiono założenia wstępne oraz realizowane funkcje. Model bazując na teorii Thevenina pozwala zadany fragment systemu, zamodelować jako źródło oraz impedancję systemową. Podejście takie umożliwia przeprowadzenie prostej analizy wpływu regulacji napięcia na wartość zapasu stabilności. Program umożliwia również wykreślanie krzywych nosowych i krzywych typu obciążenia w celu graficznego przedstawienia stanu węzła.

4

A new method of the stability margin determination of a receiving node

Brusiłowicz B, Szafran J

Present Problems of Power System Control

|

2013

|

Nr 3

s. 75--82

EN

The paper concerns the problem of local voltage instability of the power system receiving node. There were presented bases of analysis of stability margin determination using Thevenin equivalent model. Basing on Thevenin model new method of stability margin calculation was developed. The method has been described in the article. Contrary to well known methods, presented algorithm does not use a derivates of measured parameters. The algorithm uses only the measured values of steady working points. The last part of paper contains an analysis of potential errors.