Protection, Control and Optimal Operation of Microgrids with Renewable Generation

微电网是将分布式发电机组、储能设备、可控负荷在配电网的一段内协调运行，使其可以与电网并网运行，也可以作为一个自治的电力岛运行。微电网提供了一种有吸引力的结构，可以将基于可再生能源的小规模发电和热电联产（CHP）等节能技术与需求响应负荷相结合。然而，在实施微电网时遇到了一些技术挑战，特别是当发电来自风能和太阳能光伏（PV）等间歇性能源时。这些挑战包括在并联和孤岛运行模式下微电网故障保护的协调；发电机故障电流贡献有限时的故障检测；孤岛微电网储能和发电资源的优化利用并对发电和储能进行控制，以确保扰动时电压和频率的稳定。

A microgrid is formed by coordinating the operation of distributed generators (DGs), energy storage devices, and controllable loads in a section of distribution grid so that it can operate in parallel with the grid or as an autonomous power island. Microgrids provide an attractive structure to integrate small-scale generation based on renewable energy resources and energy efficient technologies such as combined heat and power (CHP) generation, and demand responsive loads. However, there are several technical challenges encountered in implementation of microgrids, especially when the generation is from the intermittent sources such as wind and solar photovoltaic (PV). These challenges include coordination of the fault protection in microgrids during both parallel and islanded modes of operation; detection of faults when the generators have limited fault current contributions; optimal use of energy storage and generation resources in islanded microgrids; and control of generation and energy storage to ensure voltage and frequency stability during disturbances.