Toward Coordinated-Voltage-Control-Enabled HV Smart Grids

In this paper we propose a Coordinated Voltage Control-Enabled HV Smart Grid framework (CVC, in short) for utilizing voltage-controllable equipment in support of enhanced reliable and efficient operations. In the first part of the paper we present the basic problem formulation underlying CVC. This is followed by assessing the effects of performance objectives selected, the type of controllable equipment used and the protocols for allocating responsibilities among Independent System Operators (ISOs) and the equipment owners (both Transmission Owners (TOs) and Generation Owners (GOs)). In the second part of the paper we describe potential benefits from the proposed CVC based on the large-scale simulations for the New England (NE), New York (NY) and Pennsylvania-Jersey-Maryland (PJM) power systems. The simulations for NE and NY power systems are carried out using an AC Extended Optimal Power Flow (AC XOPF), instead of commonly used DC OPF. The use of AC XOPF is necessary in order to assess effects of voltage-controllable equipment on the system ability to meet the desired objectives and to understand their tradeoffs. The performance objectives studied are efficiency measured in terms of generation cost, reliability measured in terms of voltage deviations from the pre-specified ranges, and power delivery to large load areas, New York City (NYC) in particular. Similarly, we report up-to-date improvements measured in terms of transmission loss minimization and management of critical voltages from using Automatic Voltage Control (AVC) in the PJM system. We conclude that the proposed CVC-Enabled HV Smart Grid could bring significant benefits to all three systems and that it would be a timely implementation. However, since the CVC architectures are non-unique it is important to fully understand the implications of their design on the achievable efficiency and reliability enhancements.