Control of Parallel DC / DC Converters in DC Microgrid

YE Youquan YANG Guanlu（Huaqiao University，Xiamen 361021，Fujian Province，China）

 

 

Abstract：This article proposes a photovoltaic （PV）DC microgrid system which employs multi-wall PV. In the DC microgrid，the droop control strategy widely used in parallel control of inverter is adopted for the control of parallel DC / DC converters，forming a triple-loop control together with voltage and current loops，which restrains the loop current between parallel DC / DC converters. Simulink simulation shows that，stable DC bus voltage and effective control over the loop current among parallel DC / DC converters can be achieved by this way. In the end，an experimental platform is built in the lab to verify the feasibility of this control strategy

Key words：photovoltaic DC microgrid；DC / DC converter；DC bus voltage；droop control；virtual impedance；loop current；triple-loop control strategy；simulation

 

    摘 要：提出以多墙体光伏为研究对象的光伏直流微网系统。将在逆变器并联控制中广泛使用的下垂控制策略应用到平行DC / DC变换器的控制中，与电压、电流环构成三闭环控制，从而抑制平行DC / DC变换器之间的环流。通过Simulink仿真分析，该方法能够实现直流母线电压的稳定及有效抑制各平行DC / DC变换器之间的环流。最后，在实验室搭建实验平台，验证该控制策略的可行性。

    关键词：光伏直流微网；DC / DC变换器；直流母线电压；下垂控制；虚拟阻抗；环流；三闭环控制策略；仿真

    中图分类号：TM615       文献标识码：A

     doi：10. 3969 / j. issn. 1003 - 8493. 2016. 03. 008