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DOE OSTI · 1777394

Voltage Estimation in Low-Voltage Distribution Grids with Distributed Energy Resources

Markovic, Marija·Sajadi, Amirhossein·Florita, Anthony·Cruickshank III, Robert·Hodge, Bri-Mathias
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Abstract

Present distribution grids generally have limited sensing capabilities and are therefore characterized by low observability. Improved observability is a prerequisite for increasing the hosting capacity of distributed energy resources such as solar photovoltaics (PV) in distribution grids. In this context, this paper presents learning-aided low-voltage estimation using untapped but readily available and widely distributed sensors from cable television (CATV) networks. The cable broadband sensors offer timely local voltage magnitude sensing with 5-minute resolution and can provide an order of magnitude more data on the time-varying state of a secondary distribution system than currently deployed utility sensors. The proposed solution incorporates voltage readings from neighboring CATV sensors, taking into account spatio-temporal aspects of the observations, and estimates single-phase voltage magnitudes at all non-monitored low-voltage buses using random forests. The effectiveness of the proposed approach was demonstrated using a multi-phase 1572-bus feeder from the SMART-DS data set for two case studies passive distribution feeder (without PV) and active distribution feeder (with PV). The analysis was conducted on simulated data, and the results show voltage estimates with a high degree of accuracy, even at extremely low percentages of observable nodes.

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24 POWER TRANSMISSION AND DISTRIBUTIONcable television networkdistributed photovoltaicslow-voltage estimationrandom forestssecondary distribution system

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BibTeXRIS

Markovic, Marija, Sajadi, Amirhossein, Florita, Anthony, Cruickshank III, Robert, Hodge, Bri-Mathias. 2021-02-19. Voltage Estimation in Low-Voltage Distribution Grids with Distributed Energy Resources. https://doi.org/10.1109/tste.2021.3060546

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