Two-Timescale Control of Smart Inverters and Legacy Devices in Unbalanced Distribution Feeders
Conference
Olowu, TO, Inaolaji, A, Paudyal, S et al. (2023). Two-Timescale Control of Smart Inverters and Legacy Devices in Unbalanced Distribution Feeders
. 10.1109/IAS54024.2023.10406521
Olowu, TO, Inaolaji, A, Paudyal, S et al. (2023). Two-Timescale Control of Smart Inverters and Legacy Devices in Unbalanced Distribution Feeders
. 10.1109/IAS54024.2023.10406521
This paper proposes two-time-scale distribution optimal flow (D-OPF) model leveraging legacy grid controllers and smart inverters (SIs) for voltage control on distribution feeders. On the slower time scale, a mixed-integer non-linear programming (MINLP) version of D-OPF provides optimal settings of on-load tap changers (OLTCs), capacitor banks, and SIs' modes and droop settings as per the IEEE-1547. On the fast time scale, using the optimal settings obtained from the first stage of the D-OPF problem, SIs' optimal active/reactive power dispatch problem is solved using a non-linear programming (NLP) model that ensures the active/reactive power setpoints lie on the SIs' droop, ensuring implementation feasibility at the local controller level. The proposed approach is demonstrated using the IEEE-123 unbalanced three-phase test feeder and compared with the case when the use of SI is not prioritized for voltage control. The results show that SIs can be prioritized to enhance the voltage control using optimal mode and droop settings while minimizing the number of operations of legacy grid control devices and optimizing active/reactive power dispatch.
