High-speed distance relaying using least error squares method and testing with FPGA

• Published in: IET generation, transmission & distribution Vol. 13; no. 16; pp. 3591 - 3600
• Main Authors: Liu, Shenyi, Jin, Xingxing (Shane), Gokaraju, Ramakrishna (Rama)
• Format: Journal Article
• Language: English
• Published: The Institution of Engineering and Technology 20.08.2019
• Subjects: data communication; data interface module; EHV‐UHV transmission systems; fast trip decision; field programmable gate array; field programmable gate arrays; FPGA; high‐speed distance relaying; high‐speed protective relaying; least error squares method; least squares approximations; LES algorithm; LES method; LES‐based relay; modern power grids; parallel architectures; parallelism architecture; pipelined architecture; power grids; power transmission faults; power transmission lines; power transmission protection; real‐time data communications; relay design; relay protection; Research Article; secure trip decision; sub‐cycle distance relaying; voltage 400.0 kV; power transmission lines; real-time data communications; field programmable gate arrays; parallel architectures; LES-based relay; FPGA; LES algorithm; LES method; parallelism architecture; relay protection; field programmable gate array; high-speed protective relaying; power transmission faults; power transmission protection; high-speed distance relaying; sub-cycle distance relaying; power grids; least squares approximations; EHV-UHV transmission systems; secure trip decision; fast trip decision; data interface module; voltage 400.0 kV; relay design; modern power grids; data communication; pipelined architecture; least error squares method
• ISSN: 1751-8687; 1751-8695; 1751-8695
• DOI: 10.1049/iet-gtd.2019.0088

The demand for high-speed protective relaying in modern power grids is growing. A relay's fast and secure operation to clear faults is critical, especially for EHV/UHV transmission systems (400 kV and above). This research proposes a sub-cycle distance relaying, which is based on the least error squares (LES) method, and with a data interface module implemented on field programmable gate array (FPGA). Taking advantage of inherent parallelism and pipelined architecture of the FPGA, the proposed relay design can support real-time data communications. Also, the flexible and reliable feature of the LES algorithm allows the proposed relay to make a fast and secure trip decision in different scenarios. The case studies demonstrate the effectiveness of the LES-based relay.