Impact of synchrophasor measurement uncertainty on detecting voltage stability margin in power systems

This study develops an analytical method for assessing the voltage stability margins of a decentralized load shedding scheme; it then examines the challenges related to the existing load shedding scheme. It also presents a practical application for implementing the proposed method, based on the synchrophasor measurement technology in modern power grid operations. By applying the concept of a continuously-computed voltage stability margin index to the configuration of the Thévenin equivalent system, the maximum transfer power could be used as an index to monitor the voltage instability phenomenon and thus determine the required load shedding amount. Thus, the calculated voltage stability margin might be a useful index for system operators in the critical decision-making process of load shedding. Dynamic simulations are performed on real Korean power systems as case studies. Simulation results, when comparing the existing and proposed methods, showed that there was a considerable reduction in the amount of load shedding in the voltage instability scenario. This indicates that the synchrophasor measurement technology has a considerable effect on the proposed load shedding method. The simulation results have validated the performance of the proposed method.

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Research on Dynamic Stability Improvement by Using STATCOM in Power System

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.960-961.1124 ◽

2014 ◽

Vol 960-961 ◽

pp. 1124-1127

Author(s):

Si Yu Li ◽

Jia Dong Huang ◽

Cui Ma

Keyword(s):

Power Systems ◽

Power Quality ◽

Voltage Stability ◽

Reactive Power ◽

Stability Margin ◽

Test System ◽

Nonlinear Loads ◽

Static Voltage Stability ◽

Voltage Stability Margin ◽

Unbalanced Loads

Nowadays, unbalanced loads or nonlinear loads produce a bad effect on the power quality of utility mains. Also, it is necessary for reactive power to be compensated because the most of industrial loads is inductive and make a lagging displacement power factor. Reactive power compensation utilizing STATCOM is one of the most important methods to improve power quality. In this paper, the technical feature of STATCOM is introduced and then a comparison with SVC is made. The effect of STATCOM on static voltage stability in power systems has been studied. Based on PSD-BPA software, effect of STATCOM is determined. Static voltage stability margin enhancement using STATCOM and SVC is compared in the modified IEEE 14-bus test system. Test results show very encouraging result.

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Impact of GICs on the Voltage Stability Margin of Power Systems

2019 IEEE AFRICON ◽

10.1109/africon46755.2019.9133807 ◽

2019 ◽

Author(s):

Ngcebo S. Sithebe ◽

David T. O. Oyedokun

Keyword(s):

Power Systems ◽

Voltage Stability ◽

Stability Margin ◽

Voltage Stability Margin

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Improvement the voltage stability margin of Iraqi power system using the optimal values of FACTS devices

International Journal of Electrical and Computer Engineering (IJECE) ◽

10.11591/ijece.v11i2.pp984-992 ◽

2021 ◽

Vol 11 (2) ◽

pp. 984

Author(s):

Ghassan Abdullah Salman ◽

Hatim G. Abood ◽

Mayyadah Sahib Ibrahim

Keyword(s):

Power Systems ◽

Power System ◽

Voltage Stability ◽

Stability Margin ◽

Voltage Collapse ◽

Voltage Profile ◽

Heavy Load ◽

Transmission Grid ◽

Facts Devices ◽

Voltage Stability Margin

The detection of potential voltage collapse in power systems is essential to maintain the voltage stability in heavy load demand. This paper proposes a method to detect weak buses in power systems using two stability indices: the voltage stability margin factor (dS/dY) and the voltage collapse prediction index (VCPI). Hence, the paper aims to improve the voltage stability of Iraqi transmission grid by allocating FACTS devices in the optimal locations and optimal sizes. Two types of FACTS are used in this paper which are Thyristor controlled series compensator (TCSC) and static var compensator (SVC). The objective function of the problem is fitted using particle swarm optimization (PSO). The proposed method is verified using simulation test on Diyala-132 kV network which is a part of the Iraqi power system. The results observed that improvement the voltage stability margin, the voltage profile of Diyala-132 kV is increased and the power losses is decreased.

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