Increasing penetration of renewable energy sources reveals the concept of dc microgrid which has the advantages of low cost and low losses because of the elimination of the AC/DC conversion processes. The most frequently encountered power quality problem in DC microgrid is voltage fluctuations due to the intermittent nature of renewable energy sources. Direct current (DC) electric spring (DCES), which is an emerging power quality device in DC microgrids, is employed in order to mitigate the effect of the related problem. In this paper, z source converter integrated DCES topology (zDCES) is proposed to provide a wide compensation voltage range with lower duty cycle range and a remarkable decrease in the battery nominal voltage in comparison with conventional systems. The proposed system composed of full-bridge converter, z source converter and battery pack. zDCES provides high voltage gain by using z source converter with passive components without any need for additional switches. The shoot-through control, which is used to achieve high gain in z source converter, is implemented using existing full-bridge switches. The performance of the proposed system is compared with the traditional DCES system. The performance of the zDCES is validated with a case study with different voltage fluctuation states.

可再生能源的日益普及揭示了直流微电网的概念，由于消除了 AC/DC 转换过程，因此具有低成本和低损耗的优点。直流微电网中最常遇到的电能质量问题是由于可再生能源的间歇性而引起的电压波动。直流（DC）电动弹簧（DCES）是直流微电网中新兴的电能质量装置，用于减轻相关问题的影响。在本文中，与传统系统相比，z 源转换器集成 DCES 拓扑 (zDCES) 被提出以提供具有较低占空比范围和显着降低的电池标称电压的宽补偿电压范围。提出的系统由全桥变换器组成，z 源转换器和电池组。zDCES 通过使用带无源元件的 z 源转换器提供高电压增益，无需任何额外的开关。用于在 z 源转换器中实现高增益的直通控制是使用现有的全桥开关实现的。所提出系统的性能与传统的DCES 系统进行了比较。zDCES 的性能通过具有不同电压波动状态的案例研究得到验证。