Abstract

The growing needs of distributed generation (DG) units in electrical power systems have a significant impact on stand-alone microgrid operation, which is increasingly faced with problems owing to low inertia. Residential, commercial, and industrial loads comprise a substantial portion of thermostatic devices (viz. air-conditioner), which leads to difficulty in managing the Demand Response (DR). Thus, in today’s microgrid scenario, the analytical study of the dynamics of such loads, along with its control, is gaining significance regarding providing ancillary services to the power network. This article presents a coordinated frequency control strategy for an impeccable demand-side management solution in a stand-alone microgrid, where, a large number of thermostatic devices are scheduled to reduce the overall energy usage during long-term operation, thus controlling the frequency in conjunction with IEC 60929 without hindering the quality of service (QoS) of the customer under various circumstances. The test system taken under consideration comprises a solar photovoltaic (PV) system with V-f control mechanism along with a battery management system (BMS), a slow responding diesel generator, and thermostatically controlled loads (TCL) of the cooling type which was simulated in Matlab/Simulink. Extensive simulation results indicate that the proposed approach can effectively manage a large number of thermostatically controlled loads to facilitate optimum demand-side management through frequency regulation under realistic conditions.

摘要

电力系统中分布式发电 (DG) 装置不断增长的需求对独立微电网运行产生了重大影响，由于低惯性，微电网越来越面临问题。住宅、商业和工业负载占恒温设备（即空调）的很大一部分，这导致难以管理需求响应 (DR)。因此，在当今的微电网场景中，对此类负载的动态及其控制的分析研究在为电网提供辅助服务方面变得越来越重要。本文提出了一种协调频率控制策略，用于独立微电网中无可挑剔的需求侧管理解决方案，其中安排了大量恒温设备以减少长期运行期间的整体能源使用，从而结合 IEC 60929 控制频率，而不会在各种情况下影响客户的服务质量 (QoS)。所考虑的测试系统包括一个太阳能光伏 (PV) 系统，其 V-f控制机制以及电池管理系统 (BMS)、慢响应柴油发电机和在 Matlab/Simulink 中模拟的冷却型恒温控制负载 (TCL)。广泛的仿真结果表明，所提出的方法可以有效地管理大量恒温控制的负载，以在现实条件下通过频率调节促进最佳需求侧管理。