Thermostatically controlled residential appliances have built-in thermodynamic storage that, even within a narrow temperature band that need not degrade the comfort level of occupants, can be used to provide a variety of value streams to power system operators and customers. Residential air conditioners and electric water heaters can be used to improve feeder power factor in a distribution system where photovoltaic systems cause the feeder power factor to dip daily, increasing losses. Under a daily optimal dispatch regime, unity power factor electric water heaters cool off in preparation for a low-feeder-power-factor event, turn on to improve the power factor during the event, and return to a neutral condition after the event. Air conditioners, with power factor lower than the feeder overall, can perform the inverse. Using a model of a real commercial and residential distribution feeder in the western United States, optimal dispatch of virtual batteries is shown to be capable of improving the daily minimum power factor by as much as 0.026. The power factor correction and optimal dispatch techniques are based on a robust virtual battery framework, making them portable to other applications such as volt-var optimization and transactive energy systems.
Revised: October 3, 2019 |
Published: July 19, 2019
Citation
Reiman A.P., A. Somani, M.E. Alam, P. Wang, D. Wu, and K. Kalsi. 2019.Power Factor Correction in Feeders with Distributed Photovoltaics Using Residential Appliances as Virtual Batteries.IEEE Access 7.PNNL-SA-142759.doi:10.1109/ACCESS.2019.2928568