Evaluation of HVDC interconnection models for considering its impact in real-time voltage stability assessment

2018 IEEE PES Innovative Smart Grid Technologies Conference Europe (ISGT-Europe)

Nielsen

2018

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This paper identifies weakness of existing method for voltage stability assessment and proposes new approach for determining point of maximum deliverable power to a given load that accounts for the variations in the Thevenin voltage magnitude. The approach uses Thevenin equivalents seen from nodes of constant voltage magnitude and load nodes in order to determine a distance to instability. A simple five-bus system together with IEEE 14 bus system were used in order to perform dynamic simulation in PSS/E. The simulation data were used to create synthetic Phasor Measurement Unit (PMU) snapshots, which served as input to the proposed approach. The new approach is demonstrated on the two test systems, where improved accuracy in determining the point of maximum deliverable power is demonstrated. The results show that the point of maximum deliverable power to the load occurs well before the Thevenin impedance matching criteria.

Section: Introductionmentioning

confidence: 99%

Improved Voltage Stability Boundary Monitoring by Accounting for Variations in Thevenin Voltage Magnitude

Karatas

2018 IEEE PES Innovative Smart Grid Technologies Conference Europe (ISGT-Europe)

Nielsen

2018

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Improved Thévenin equivalent methods for real-time voltage stability assessment

Perez

2016 IEEE International Energy Conference (ENERGYCON)

Østergaard

et al. 2016

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Abstract-An improved Thévenin equivalent method for realtime voltage stability assessment that uses wide-area information from synchrophasors is proposed. The improvements are a better modeling of the limited synchronous generators, and a processing that anticipates the effect of field current limiters, before the latter are activated. Several study cases using detailed dynamic simulations of the Nordic test system have been used to assess the performance of the proposed improvements. Their effectiveness is analyzed and, based on the results, their possible application in combination with the sensitivity-based voltage stability assessment method is explored.

Considering wind speed variability in real-time voltage stability assessment using Thévenin equivalent methods

Perez

Karatas

2017 IEEE Manchester PowerTech

et al. 2017

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In this paper, wind speed models are used to consider its variability in real-time voltage stability assessment using Thévenin equivalent methods. A stochastic differential equation was used to produce a set of wind speeds required for the simulation scenarios together with a very short-term forecast based on a probabilistic method, which provides the means for including anticipation in the stability assessment. This is achieved by representing the variation in the wind as an uncertainty in the Thévenin equivalent parameters, which are used for wide-area assessment, and studying corresponding changes in the stability boundary for a specific time horizon. The methodology was tested with time domain simulation a cigré benchmark system for network integrations of renewables, where the approach successfully represented the final Thévenin Equivalent parameters with a maximum error of 2.5% of the estimated variables, for a time horizon of 1 minute in the used forecast.