The architectural design and protocol selection in DC protection testing

Because of the lack of single test methods for DC protection system in converter station, this paper firstly analyzes the difference between DC protection system and relay protection device in substation, and explains that DC protection system has its own characteristics and cannot copy the whole way of relay protection device. On the base of the detailed analysis of the development history and standard evolution of the control and protection system of substation and converter station, a general test architecture scheme is proposed, which can be used for the single test of DC protection system on the premise of making full use of the existing relay protection tester, that is, the way of adding the specification conversion device in the middle. At the same time, based on analyzing the characteristics of various standard protocols, IEC 60044-8 is selected as the communication protocol between the tester and the protocol conversion device. Based on this architecture and protocol, the single test of the DC protection system is realized.