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We present a feasibility analysis of the controlled delivery power grid (CDG) that uses aggregated power request by users to reduce communications overhead. The CDG, as an approach to the power grid, uses a data network to communicate requests and grants of power in the distribution of electrical power. These requests and grants allow the energy supplier know the power demand in advance and to designate the loads and the time when power is supplied to them. Each load is assigned a power-network address that is used for communication of requests and grants with the energy supplier. With addressed loads, power is only delivered to selected loads. However, issuing a request for power before delivery takes place requires knowing the demand of power the load consumes during the operation interval. However, it is a general concern that having issuing requests in a time-slot basis may risk request losses and therefore, generate intermittent supply. Therefore, we propose request aggregation to minimize the number of requests issued. We show by simulation that the CDG with request aggregation attains high performance, in terms of satisfaction ratio and waiting time for power supply.
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Voltage Collapse Stabilization in Star DC Networks
Voltage collapse is a type of blackout-inducing dynamic instability that occurs when the power demand exceeds the maximum power that can be transferred through the network. The traditional (preventive) approach to avoid voltage collapse is based on ensuring that the network never reaches its maximum capacity. However, such an approach leads to inefficiencies as it prevents operators to fully utilize the network resources and does not account for unprescribed events. To overcome this limitation, this paper seeks to initiate the study of voltage collapse stabilization. More precisely, for a DC star network, we formulate the problem of voltage stability as a dynamic problem where each load seeks to achieve a constant power consumption by updating its conductance as the voltage changes. We show that such a system can be interpreted as a game, where each player (load) seeks to myopically maximize their utility using a gradient-based response. Using this framework, we show that voltage collapse is the unique Nash Equilibrium of the induced game and is caused by the lack of cooperation between loads. Finally, we propose a Voltage Collapse Stabilizer (VCS) controller that uses (flexible) loads that are willing to cooperate and provides a fair allocation of the curtailed demand. Our solution stabilizes voltage collapse even in the presence of non-cooperative loads. Numerical simulations validate several features of our controllers.
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- PAR ID:
- 10106065
- Date Published:
- Journal Name:
- American Control Conference
- Page Range / eLocation ID:
- 1957 to 1964
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.23919/ACC.2019.8814708
