The frequent start/stop operation of a bow thruster presents a high pulsating power demand in shipboard microgrids while reducing the fuel efficiency of the diesel engines, which may induce potential instabilities. In this article, a hybrid energy storage system, including batteries and ultracapacitors (UCs), is connected to the dc bus of the thruster driver, and a hierarchical controller is proposed for the bidirectional dc/dc converters that interface storages, thus providing the following functions: 1) the diesel generator (DG) sets provide the required average power to the bow thruster; 2) the batteries smooth the active power fluctuations; and 3) the UCs provide the pulsating active power due to the slow charging response of batteries. A $V - I$ droop control and high-/low-pass filters are used inside the primary controller to proper power sharing between storages in different time scales. The secondary controller is developed to ensure the power from the DG sets to the bow thruster being equal to the required average power. Simulation results shows that this control scheme can effectively reduce the capacity of DG sets and batteries and can improve the fuel consumption efficiency. When the thruster machine operates as a generator during fast breaking, the hybrid energy storage can absorb the braking energy.

中文翻译：

---

提高船用微电网能效的运行控制，包括船首推进器和混合储能

船首推进器的频繁启动/停止操作在船载微电网中提出了高脉动功率需求，同时降低了柴油发动机的燃料效率，这可能会导致潜在的不稳定性。在本文中，包括电池和超级电容器 (UC) 的混合储能系统连接到推进器驱动器的直流总线，并为连接存储的双向 dc/dc 转换器提出了分层控制器，从而提供以下内容功能： 1）柴油发电机组（DG）为船首推进器提供所需的平均功率；2）电池平滑有功功率波动；3) 由于电池的缓慢充电响应，UCs 提供脉动有功功率。主控制器内部使用了 $V - I$ 下垂控制和高通/低通滤波器，以在不同时间尺度的存储之间进行适当的功率共享。二次控制器的开发是为了确保从 DG 装置到船首推进器的功率等于所需的平均功率。仿真结果表明，该控制方案能够有效降低DG组和蓄电池的容量，提高油耗效率。当推进器在快速制动时作为发电机运行时，混合储能可以吸收制动能量。仿真结果表明，该控制方案能够有效降低DG组和蓄电池的容量，提高油耗效率。当推进器在快速制动时作为发电机运行时，混合储能可以吸收制动能量。仿真结果表明，该控制方案能够有效降低DG组和蓄电池的容量，提高油耗效率。当推进器在快速制动时作为发电机运行时，混合储能可以吸收制动能量。