Distributed and real-time economic dispatch strategy for an islanded microgrid with fair participation of thermostatically controlled loads

Abstract

Thermostatically controlled loads (TCLs) are viewed as a promising demand-side resource for smoothing out the intermittency of renewable energy. However, it is difficult to dispatch these dispersed flexibility resources to serve the microgrid without establishing the aggregation model of TCLs. Motivated by this need, this paper presents a distributed and real-time economic dispatch strategy based on the alternating direction multiplier method, that allows TCLs and distributed generations to work in coordination to maintain the power balance of islanded microgrids under fluctuating renewable energy sources, while considering the occupant comfort and the fair utilization. A semi-online parameter identification method that does not involve occupant privacy is proposed for obtaining parameters of inverter-based TCLs. This method is based on recursive least squares and designed with a changing forgetting factor to avoid data saturation. Also, a virtual battery model considering parameter heterogeneity is established for TCLs, and the scheduling capability of the TCLs cluster under different ambient temperatures is determined using deep neural networks. Besides, this paper introduces a fast distributed consensus algorithm without changing the communication structure to improve the convergence speed of the distributed algorithm. The effectiveness of the proposed strategy is validated on an islanded microgrid with 100 TCLs.