Controlling DC microgrids in communities, buildings and data centers

Abstract

Microgrid technology is poised to transform the electricity industry. In the context of commercial/domestic buildings and data centers, where most loads are native direct current, DC microgrids are in fact a natural choice. Voltage stability and current/power-sharing between sources within a DC microgrid have been studied extensively in recent years. DC voltage droop control is known to have its drawbacks in that current or power-sharing is relatively poor. To eliminate this drawback, some have proposed to add a communication-based consensus control in addition to the primary voltage droop control loop. The current sharing performance is improved, however, the voltage deviation inherent in droop control requires a further, slower control to achieve voltage quality control. To overcome this complication, and reduction in response time, a low latency communicationbased control technique that achieves proportional current sharing without significant voltage deviations is proposed in this work. The stability of the proposed control technique is compared to state-of-the-art using eigenvalue and transient analyses. The negative impact of communication delays on proposed control is discussed in detail.

A Nonlinear Control Strategy for DC-DC Converter with Unknown Constant Power Load Using Damping and Interconnection Injecting

“…With the development of the DC Microgrid (DM), the DM is becoming an effective way of distributing power supplies [1][2][3]. Meanwhile, the DC-DC converters (DDCs) are becoming increasingly common and play an important role in the DM due to their advantages in efficiency, flexibility, isolation, controllability, etc.…”