Partially Rated Power Flow Control Converter Modeling for Low-Voltage DC Grids

Abstract

Scalable and robust low voltage direct current distribution (lvdc) networks require solutions allowing flexible power flow control and reliable short-circuit protection. In this paper, the continuous full-order large and small signal models of a partially rated power flow control converter (PFCC) are derived utilizing the generalized averaging method. The large signal model of the PFCC is coupled with a model of the lvdc grid. Due to the state-space representation the combined model of the PFCC and the lvdc grid is suitable for easy algorithmization, and efficient simulation. These advantages make them essential tools for studying and optimizing of scalable lvdc systems with decentralized power flow control based on the PFCC. The PFCC models provide insights into controller design and stability analysis. The models are experimentally validated, and the functionality of the PFCC is demonstrated in a laboratoryscale microgrid.

Coordination Control of Power Flow Controller and Hybrid DC Circuit Breaker in MVDC Distribution Networks

“…NETWORK AND ITS TOPOLOGY Figure 1(a) presents the topology of SP-PFC and hybrid DCCB [23], [24]. The SP-PFC consists of a dual active bridge (DAB) and a full-bridge converter (FBC).…”

“…In comparison with parallel PFC, series-parallel PFC (SP-PFC) only needs to process partial rated PF. Therefore, the SP-PFC is cost-effective [23], [24]. Furthermore, when regulating the PF, the SP-PFC does not rely on the power exchange between different DC lines.…”

Transformer Current Ringing in Dual Active Bridge Converters

“…, due to its simple topology and control, galvanic isolation, bidirectional power flow, wide input and output voltage adaptive range, high power density, and efficiency, is very promising in applications like Solid State Transformers (SST) [2][3][4], electric vehicle chargers with V2G concept [5] [6], power flow control in DC grids [7][8][9], etc.…”

Design criteria of solid‐state circuit breaker for low‐voltage microgrids

“…Using the solid‐state circuit breaker (SSCB) on the low‐voltage side to protect the substation is favourable compared to implementing the protection on the medium voltage side as the SSCBs do not have to be rated for high overvoltages. The houses are connected to the microgrid via SSCBs; the power flow in the grid can be controlled with power flow control converters such as [7]. Inside the house, several protection groups can be defined similarly as is done in the contemporary electric installations.…”

“…Direct current houses can be connected to the microgrid via SSCBs instead of fully rated dc/dc converters to make the system more efficient. The power flow in the grid can be controlled with power flow control converters [7]…”