سیستم مدیریت بهینه انرژی چند میکروگریدی
Abstract
Nomenclature
۱٫ Introduction
۲٫ Energy management model of the NMGs
۳٫ Model description
۴٫ Illustrative implementations
۵٫ Conclusions
Declaration of Competing Interest
References
Abstract
This paper proposes a novel energy management system (EMS) for an isolated structure of networked microgrids (NMGs). The interconnected microgrids consist of the cyber-physical connections for information and power exchanges. A bi-level EMS is presented in which the outer-level EMS is aimed to exchange the required information and power between the interconnected microgrids, and the inner-level EMS is intended for energy scheduling of each on-fault microgrid in case of separation from other microgrids. This paper focuses on the operation of interconnected microgrids. A step-wise demand response program (DRP) is also considered in the energy management to attain the cost-effective operation. Furthermore, a new pricing model based on microgrid marginal pricing (MGMP) is introduced for the power exchanges between the interconnected microgrids. To cope with the uncertainties of the renewable energy sources and loads, some scenarios are generated using the scenario-based analysis. Also, a backward scenario reduction method is used to reduce the number of the scenarios. Besides, a mixed integer linear programming (MILP) is applied to the stochastic optimization problem of the NMGs. The proposed model is implemented on a test system with five NMGs. The simulation is run over a 24- hour scheduling time horizon. Both cases without and with demand response program (DRP) are compared in the numerical results. The results of the simulation demonstrate that using the proposed DRP in the energy management increases the performance of the generation units and decreases the total operational cost of the proposed NMGs. Also, the voltages of the buses converge to their rated values.
Introduction
Environmental concerns and rising energy consumption today increase the usage of distributed energy resources, energy storages (ESs) and demand response programs (DRP). Besides, renewable energy sources (RES) play an important role in clean energy generation [1]. Although controlling many these resources presents difficult challenges in the safe and efficient operation of the network, these challenges are managed by the concept of microgrid [2]. Microgrid is a distribution system consisting of distributed generations (DGs), ESs and responsive loads. Indeed, microgrids are operated as an interconnected or isolated network. From the upstream grid perspective, the microgrid is a controllable system that is operated as a controllable load or a power source. In grid-connected mode, the microgrids send or receive power from the main grid and other microgrids in the system. However, factors such as major disruption to the main grid, decreasing the power quality of the main grid according to the certain standards, or maintenance programs cause to isolate the microgrid from the main grid [3–۵]. Given the uncertainties in DER, the availability of ESs and responsive loads along with RES-based DGs is a proper solution for achieving higher reliability and ensuring balance between generation and load demand in the microgrids. This issue not only delays the increase of the generation capacity, but also reduces system operating costs and greenhouse gas emissions. Furthermore, deploying a microgrid can facilitate the implementation of the efficient DRP [6,7].