A Bi-Layer Multi-Time Coordination Method for Optimal Generation and Reserve Schedule and Dispatch of a Grid-Connected Microgrid

Abstract

With the integration of more microgrids in distribution networks, its optimal autonomous operation becomes more important to reduce its operating cost and its influence on the main grid. This paper proposes a bi-layer multi-time coordination method for optimal generation and reserve schedule and dispatch of a grid-connected microgrid to reduce the impact of uncertainties of renewable sources, loads, and random component failures on power balance, operating costs, and system reliability. The reserve is refined into positive and negative reserves related to power shortage and power surplus. In the days ahead schedule layer, generating units are committed, and relaxed bidirectional reserve boundaries are predicted for the next day. In the real-time dispatch layer, generation output is dynamically adjusted and the reserve is dispatched using a successive approximation based on real-time data. A test microgrid is analyzed to illustrate the effectiveness of the proposed approach.

Forecast-Based Consensus Control for DC Microgrids Using Distributed Long Short-Term Memory Deep Learning Models

“…The main approach for ESS management is based on keeping the ESSs fully charged to respond to supply failure, disregarding the load behavior and generation forecast [18]. For centralized small size microgrids, this approach works well, as the ESSs are managed centrally [18].…”

“…The main approach for ESS management is based on keeping the ESSs fully charged to respond to supply failure, disregarding the load behavior and generation forecast [18]. For centralized small size microgrids, this approach works well, as the ESSs are managed centrally [18]. However, for distributed microgrids with low inertia of the operating point and the intermittent behavior of RES, ESSs are used to establish voltage stability and accurate SoC balancing [3], [19].…”

Load control mechanism for operation of microgrids in contingency state

“…The main drawback of these papers is that they only focus on the static aspects of the emergency conditions, and ignore the frequency deviation of the MG in the contingency state. Lei et al [21] scheduled the MG in two stages. At first, hourly scheduling is performed and the second stage modifies its decisions considering time steps near the real‐time operation.…”

“…In summary, the following shortcomings can be identified in the literature of the MG's short‐term operation: • No attention into the impact of frequency deviation on the successful islanding of the MG in [16, 19, 21–25]. • No investigation into the load's vulnerability model in the critical condition of the contingency states in [5, 10, 12].…”

Multi-Time Scale Optimal Dispatch for AC/DC Distribution Networks Based on a Markov Chain Dynamic Scenario Method and MPC

“…In [16], a multi-time scale optimal dispatch method was applied since the accuracy of wind turbine and load prediction gradually increased with time scale subdivision, and this method effectively increased the proportion of wind turbine consumption. In [17], a multi-time active power coordination scheduling method was proposed based on the idea of level by level subdivision and mutual coordination to correct the error between the forecast value and the actual value in the next layer.…”