The Hybrid HVDC Breaker An innovation breakthrough enabling reliable HVDC grids

TLDR

Existing mechanical HVDC breakers interrupt currents in tens of milliseconds, which is too slow for reliable HVDC grids, while semiconductor‑based breakers offer faster operation but incur large transfer losses of about 30 % of a voltage‑source converter station’s losses. ABB developed a hybrid HVDC breaker to address speed and loss issues, and this paper details its design principles and test results. The hybrid breaker features a modular design for HVDC applications, and its integration into an HVDC switchyard is discussed. The hybrid design achieves negligible conduction losses while maintaining ultra‑fast current interruption capability.

Abstract

SUMMARY Existing mechanical HVDC breakers are capable of interrupting HVDC currents within several tens of milliseconds, but this is too slow to fulfill the requirements of a reliable HVDC grid. HVDC breakers based on semiconductors can easily overcome the limitations of operating speed, but generate large transfer losses, typically in the range of 30 percent of the losses of a voltage source converter station. To overcome these obstacles, ABB has developed a hybrid HVDC breaker. The hybrid design has negligible conduction losses, while preserving ultra-fast current interruption capability. This paper will present a detailed description of the hybrid HVDC breaker, its design principles and test results. The modular design of the hybrid breaker for HVDC applications is described. Furthermore, the application of the hybrid breaker associated with the design of a HVDC switchyard will be discussed.