Research Of Software-only Testing System For Protective Relay Based On IEC61850

With the development of digital substation, distributed generation technology and the publishment of IEC61850, the new protection equipment popularized more and more. At the same time, the new digital protection device performance testing is also facing new challenges. Protective relay test technology and test tools will progress. Relay protection test by the steady-state transition to a comprehensive test of the dynamic and transient; transition to a closed-loop test by the open-loop test; non-real-time transition to real-time. Microcomputer-based test equipment will continue to develop miniaturized, intelligent, and digital is the direction of its development. RTDS-represented on the all-digital simulation system, as the new mathematical model of the power system components and the emergence of the new algorithm constantly improve its cost will continue to drop, so as to provide more real, effective, and feasible protective relay test environment. Because of a better cost-effective PC-based real-time digital simulation system will obtain a wider range of applications.Generally, planning and design stages of power system rely on a powerful and non-real-time computer simulation software, and protection equipment installed, new technology and new equipment puted into operation before you need to use simulation tools to verify to determine whether the actual operation to achieve the expected goals. Due to the limitations of the physical simulation of cost, scale and flexibility, making the development of real-time digital power system simulation technology has become particularly important. The real-time digital simulation of the power system, there are some successful experience and the development of some new equipment. However, taking into account the cost, function and special protection equipment for real-time digital simulation test system remains to be further studied. Therefore it has important practical significance and great applied value to research digital protection testing methods and develop new testing systems.This topic is new technology, combined with the currently popular power system simulation tools and IEC61850standard corresponding new requirements. The proposed development and utilization of WinPcap the IEC61850process layer communication functions protection equipment pure software real-time closed-loop digital simulation test system. In order to solve the traditional digital simulation test system physical originals expensive, use inflexible, inconvenient problem.After analyzing the requirement of digital protection test and current testing solutions, at first this paper chose the software-only real-time testing system for protective relay as the research orientation. After understanding the requirements and principles of real-time simulation and process layer communication, proposed to achieve real-time simulation based on MATLAB and using WinPcap achieve process layer communication function solutions.Then, discussed in detail how to use MATLAB to achieve real-time simulation and validation through experimental tests; developed process layer communication function by WinPcap and the IEC61850format determining of the data packet.At last, using existing digital protection device through test experiments to test functionality of testing system developed. Through many test results show that the system worked smoothly and the communication performance was corresponding to IEC61850.Eventualy,target of the research topic was achieved.