A Development Platform of Transient Based Protection for EHV Transmission Lines

In order to dynamically test the algorithms of transient based protection for EHV transmission lines, this paper presents a hardware platform, which is composed of two parts. The first part, transient based protection prototype machine (PM), is essentially a computer-based relay that can sample transient signals and execute protection programs in a real time way. The second part, power system transient signal generator (TSG), is set up to provide high-frequency transient signals for PM testing. Virtual instrument technique is adopted as controlling software to accelerate development speed and improve the performance of the whole hardware platform. Simulation studies, with responses to various systems and fault conditions, have shown that the first part of the platform is capable of sampling continuously transient signals with 400 KHz and running real-time protection calculation, and that the second part is able to reproduce transient signals without distortion