The Design And Research Of High-voltage Line Digital Protection Software Based On The Electronic Transformers

Having the advantages of insulation requirements, accuracy, security, digital and automated matching capability, Electronic Transformers will become a ideal alternative for the traditional power transformer. At the same time, how to achieve the interface between electronic transformers and secondary equipment has become a hot issue of the study. Hunan University and Wuhan Yangtze Communications Corporation signed the "Research on microprocessor protection interfaced with Electronic Transformer" issues, topics and research work of this paper is an important part of the subject, with theoretical and practical value.First, described the principle of Electronic Transformer and the status of study at home and abroad, and discussed the characteristics of Electronic Transformers and the impact of its application, then researched the characteristics and communication technologies of Electronic Transformers digital output in the IEC60044-8 and IEC61850-9 standards. The sampling rate of MU and protection device was not the same, secondary devices can not point out the sampling value simply. Aimed at this situation, used linear interpolation algorithm to solve it, and analyzed its error. According to Simulation of Matlab,Linear interpolation with high precision easily facilitates the realization, reducing the workload of the research and development.Based on the configurations of typical high-voltage transmission line relay protection devices, discussed in detail the main protection configuration and its working principles. In addition, research protection algorithms and measurement criteria used in software, some of these algorithms were derived in detail.Protection module was the core of the entire software, it was divided into the main program, the value of sampling receiving interrupt service and fault processing module. Used relay-oriented, hierarchical, modular design method to complete the software design of protection the method divided protection software into Framework layer, the functional layer and layer drive, with a clear division of labor and simple interface. The paper explained the process diagram in detail, and introduced design ideas, gave the concrete realization of the various functional modules.