Improved Dynamic Voltage Regulation in a Droop Controlled DC Nanogrid Employing Independently Controlled Battery and Supercapacitor Units
Improved Dynamic Voltage Regulation in a Droop Controlled DC Nanogrid Employing Independently Controlled Battery and Supercapacitor Units
复制标题
采用独立控制电池和超级电容器单元改进下垂控制直流纳米电网的动态电压调节
DOI：
10.3390/app8091525
复制
发表时间：
2018
期刊：
影响因子：
--
通讯作者：
L. Lopes
中科院分区：
文献类型：
--
作者：
Ahmad Malkawi;L. Lopes
直流母线电压信号 (DBS) 和下垂控制经常用于直流纳微电网和微电网，以及以分散方式运行的分布式能源 (DER)。这种方法可以有效地在稳态条件下实现电源和储能系统 (ESS) 的预期贡献。在混合储能系统（HESS）中使用超级电容器（SC）和电池可以减轻高且快速的电流变化对电池单元的损耗和寿命的影响。然而，通过将 HESS 作为单个单元进行控制，人们会丧失 SC 的潜在贡献及其高功率能力，无法动态改善直流纳米电网中的电压调节。本文讨论了一种独立于电池接口控制 SC 接口的方法，具有小下降因子和高通滤波器 (HPF)，以产生高且短的电流脉冲，并平滑由于直流纳米电网中突然功率不平衡而导致的直流母线电压变化。实验结果表明，与传统的 HESS 不同，SC 单元可用于改善直流纳米电网的动态电压调节，并间接缓解电池中高且快速的电流变化。
DC bus voltage signaling (DBS) and droop control are frequently employed in DC nano and microgrids with distributed energy resources (DERs) operating in a decentralized way. This approach is effective in enforcing the desired contributions of power sources and energy storage systems (ESSs) in steady-state conditions. The use of supercapacitors (SCs) along with batteries in a hybrid energy storage system (HESS) can mitigate the impact of high and fast current variations on the losses and lifetime of the battery units. However, by controlling the HESS as a single unit, one forfeits the potential contribution of the SC and its high power capabilities to dynamically improve voltage regulation in a DC nanogrid. This paper discusses an approach where the SC interface is controlled independently from the battery interface, with a small droop factor and a high pass filter (HPF), to produce high and short current pulses and smooth DC bus voltage variations due to sudden power imbalances in the DC nanogrid. Experimental results are presented to show that, unlike in a conventional HESS, the SC unit can be used to improve the dynamic voltage regulation of the DC nanogrid and, indirectly, mitigate the high and fast current variations in the battery.