A Multi-Function Integrated Circuit Breaker for DC Grid Applications

Abstract

The protection and current flow regulation of highvoltage direct-current (HVDC) grids requires the deployment of additional semiconductor-based equipment including dc circuit breakers (DCCBs) and current flow controllers (CFCs). However, the inclusion of multiple devices could significantly increase the total cost of an HVDC system. To potentially reduce costs, this paper presents an innovative multi-function integrated DCCB (MF-ICB). The proposed device exhibits a reduced number of semiconductor switches and can fully block dc faults at different locations while regulating dc currents. The configuration of the integrated solution and its operating principle are assessed, with its performance being examined in PSCAD/EMTDC using a three-terminal HVDC grid. Simulation results demonstrate the capability and effectiveness of the MF-ICB to regulate grid current and isolate dc faults.

A Low-Loss Integrated Circuit Breaker for HVDC Applications

“…A major advantage of the low-loss ICB introduced in this paper compared to other alternatives found in the literature is its capability to protect multiple nodes with a single device. It should be emphasized that the ICB topologies presented in [20], [21], [42] also achieve this. The ICB in [21] features a significantly lower number of semiconductors by including additional UFDs or diodes.…”

“…Other DCCB topologies using fewer semiconductor devices to block fault currents than typical HCBs have been designed [20], [21], [41], [42]. They achieve this by using a single IGBT string to block fault current, while extra switchgear (e.g.…”

“…The ICB in [20] has a reduced number of both semiconductor switches and surge arresters. Reference [42] considers the functionality of dc current flow control embedded within the device. However, the devices in [20], [21], [42] consider LCSs at their load current branches, which increases power losses-such a shortcoming is avoided by the low-loss ICB introduced this paper.…”

Multi‐vendor interoperability in HVDC grid protection: State‐of‐the‐art and challenges ahead

“…Recent developments on DCCB technology focus on reducing losses or component counts while maintaining high performance [36,41] and developing multi-functional devices [42,43]. Zero steady-state loss can be achieved for a hybrid DCCB by using an inductance coupled circuit to generate a negative voltage to force the current commutation from the load current branch to the main breaker branch [36].…”

“…Additional ultra-fast disconnectors may be used to maintain bidirectional fault current interruption while only using unidirectional power electronic switches [41]. Another trend is developing multifunctional and multi-port DCCBs to have integrated fault current interruption, limiting and power flow control aiming at reducing component counts [42,43].…”