Algorithms for Power System State Estimation with Phasor Measurement Units

Loading...
Thumbnail Image

URL

Journal Title

Journal ISSN

Volume Title

School of Electrical Engineering | Doctoral thesis (article-based) | Defence date: 2021-07-30

Date

2021

Major/Subject

Mcode

Degree programme

Language

en

Pages

100 + app. 66

Series

Aalto University publication series DOCTORAL DISSERTATIONS, 83/2021

Abstract

Power system state estimation (PSSE) is one of the key components in the suite of computational tools which assist in managing the day to day operations of electric grids. In recent years, two trends have emerged as the world transitions towards smart grids: The first is the introduction of new measurement and protection devices called phasor measurement units (PMUs). The second is the creation of transmission system operators (TSOs) as part of a general move away from vertically integrated monopolies. These TSOs are charged with ensuring the fair and reliable operation of the power system. This thesis proposes new algorithms for PSSE which address the implications of these trends. This thesis introduces a novel approach to state estimation with PMUs where we decouple the estimation of PMU observable and PMU unobservable state variables. We show that this approach has several advantages like improved numerical stability, reduced computational complexity and robustness to time-skew errors. Next, we develop a signal-dependent scheme to choose how many PMU measurements to average over to obtain a more precise estimate of the underlying voltages. This method shows an improvement over the state-of-the-art approach. This thesis also develops methods for using PMUs for multi-area state estimation (MASE). These methods are based on a novel information exchange scheme called clustered gossip and share. We derive analytical results which prove that this approach always results in reduced information exchange when compared to a naive approach to network gossiping. This approach is applied to the traditional measurement-approach, the previously derived reduced-order approach, and also a novel privacy preserving approach for linear power system state estimation. Also presented in this thesis is a novel event-triggered approach to hierarchical multi-area state estimation. The main idea of this algorithm is that the state estimator in each area communicates with neighboring areas only when such an action is informative. This approach is shown to reduce the amount of communication, and also reduces the computational load involved in calculating the state estimation.

Description

Defence is held on 30 July 2021 at 12:00. Zoom link: https://aalto.zoom.us/j/63793176232

Supervising professor

Wichman, Risto, Prof., Aalto University, Department of Signal Processing and Acoustics, Finland

Thesis advisor

Werner, Stefan, Prof., NTNU, Norway
Huang, Yih-Fang, Prof., University of Notre Dame, USA

Keywords

smart grids, power system state estimation, distributed estimation

Other note

Parts

  • [Publication 1]: N. Kashyap, S. Werner, T. Riihonen and Y.-F. Huang. Reduced-order synchrophasor-assisted state estimation for smart grid. In IEEE International Conference on Smart Grid Communications (SmartGridComm), Tainan City, Taiwan, November 2012.
    DOI: 10.1109/SmartGridComm.2012.6486052 View at publisher
  • [Publication 2]: N. Kashyap, S. Werner, Y.-F. Huang, and T. Riihonen. Power System State Estimation Under Incomplete PMU Observability–A Reduced-Order Approach. IEEE Journal of Selected Topics in Signal Processing, Volume 8, Issue 6, pp. 1051-1062, December 2014.
    DOI: 10.1109/JSTSP.2014.2333712 View at publisher
  • [Publication 3]: N. Kashyap, S. Werner, J. Lundén. Signal-Dependent Preprocessing of Buffered PMU Measurements for Hybrid State Estimation. In IEEE International Instrumentation and Measurement Technology Conference (I2MTC), Taipei, Taiwan, May 2016.
    DOI: 10.1109/I2MTC.2016.7520340 View at publisher
  • [Publication 4]: N. Kashyap, S. Werner, Y.-F. Huang. Decentralized power system state estimation with reduced inter-area communication. In IEEE International Conference on Digital Signal Processing (DSP), Singapore, July 2016.
    DOI: 10.1109/ICDSP.2015.7251322 View at publisher
  • [Publication 5]: N. Kashyap, S. Werner, Y.-F. Huang. Decentralized PMU-assisted Power System State Estimation with Reduced Interarea Communication. IEEE Journal of Selected Topics in Signal Processing, Volume 12, Issue 4, pp. 607-616, August 2018.
    DOI: 10.1109/JSTSP.2018.2849219 View at publisher
  • [Publication 6]: N. Kashyap, S. Werner, Y.-F. Huang. Event-triggered multi-area state estimation in power systems. In IEEE International Workshop on Computational Advances in Multi-Sensor Adaptive Processing (CAMSAP), San Juan, Peurto Rico, December 2011.
    DOI: 10.1109/CAMSAP.2011.6135905 View at publisher
  • [Publication 7]: N. Kashyap, S. Werner, Y.-F. Huang. Privacy Preserving Decentralized Power System State Estimation with Phasor Measurement Units. In IEEE Sensor Array and Multichannel Signal Processing Workshop (SAM), Rio de Janeiro, Brazil, July 2016.
    DOI: 10.1109/I2MTC.2016.7520340 View at publisher

Citation