Distributed control and energy storage requirements of networked Dc microgrids

Abstract

a b s t r a c tMicrogrids are a key technology to help improve the reliability of electric power systems and increase the integration of renewable energy sources. Interconnection and networking of smaller microgrids into larger systems have potential for even further improvements. This paper presents a novel approach to a distributed droop control and energy storage in networked dc microgrids. Distributed control is necessary to prevent single points of failure along with flexibility and adaptability to changing energy resources. The results show that systems with random sources and fast update rates, a networked microgrid structure can minimize required energy storage requirements.

Decentralized Mode-Adaptive Guidance and Control for DC Microgrid

“…A HSSPFC approach to droop control is presented in [15] that uses the distributed energy storage device co-located with the source to actuate the droop control as opposed to the common method of feedback control of the duty cycle. The Hamiltonian-based droop control of [15] is more decentralized than the DMA guidance law presented above since it does not broadcast the bus storage to all source converters.…”

“…The Hamiltonian-based droop control of [15] is more decentralized than the DMA guidance law presented above since it does not broadcast the bus storage to all source converters.…”

“…The droop current each source supplies to the bus, i dref,j , is used to create an error signal [15] e i = i dref,j − i j λ j , j = 1 . .…”

“…Decentralized control eliminates the single point of failure inherent in centralized control. One common form of decentralized microgrid control is droop control [14], [15]. The reduced communication network does come with drawbacks.…”

“…A fundamental component of the OXD power apportionment method is based on a Hamiltonian Surface Shaping Power Flow Control (HSSPFC) approach [13], [22]. The droop control method presented in [15] also uses a HSSPFC approach; thus, for comparison, the work of [15] is used as the corresponding fully decentralized control scheme to the OXD power apportionment strategy. The DMA power apportionment strategy is also built on a HSSPFC approach and aims to fill the void between the droop control and OXD.…”