The Automated System of Unified Templates as an Element of Trainability of Microprocessor Relay Protection Devices

The article discusses the possibility of further modernization of the standard microprocessor relay protection of AC overhead system feeders DPA-27.5-TNF, which is operated on the Trans-Baikal Railway by creating an additional automated system of unified templates necessary for the occurrence of “trainability” elements. The templates will be formed via a separate dedicated channel for transmission, processing and storage of the necessary information, not related to the operation of the terminal, with its subsequent visualization at the workplace of the duty personnel of traction substations, together with information from the “GID” software received via another dedicated wired channel. With the help of such a base of unified preset templates, in the future, it will be possible not only to identify the specific causes of each emergency shutdown but also to reduce their number by dynamically adjusting the existing presets of the standard operation algorithm.

Comprehensive Automation of Microprocessor Protection Relay Terminals Operated on AC Railways

The article discusses the possibility of a potential reduction in the number of operations of microprocessor relay protection of feeders of the contact network of AC railways TsZA-27.5-FKS (FTS) for unknown reasons. Real statistics on the number of microprocessor relay protection operations at the Buryatskaya traction substation are presented, simulation of the real train situation (in accordance with the regime maps of the throughput capacity of the sections of the Trans-Baikal railway) was carried out in the specialized software complex “KORTES”. Based on the results of the analysis of simulation modeling, the process of forming a unified template of settings using neural network technologies is considered, which characterizes only this specific regular train situation. To protect objects in the event of pre-emergency and emergency modes of operation of the traction power supply system, a variant of changing the standard operation algorithm of the TsZA-27.5-FKS (FTS) terminal by introducing additional blocks for calculating the predictive functions of current and voltage has been proposed.

Analysis and discussion of a dead-zone protection mal-operation case in Brazil

A mal-operation case of busbar protection caused by a dead-zone protection abnormality in the Brazilian Midwest Grid on September 19th,2012,is briefly described.The operation process of pilot distance,automatic re-closure,busbar differential and dead-zone protection,and the emphasis on the logic scheme of dead-zone protection are analyzed.The time delay between the breaker’s main pole and auxiliary contact during re-closure was the main cause in this case,and a defect in the logic allowed it to occur.The differences in dead-zone protection logic between Brazil and China are discussed.A test platform was constructed in the laboratory,and a site simulated experiment was also performed.Possible causes are suggested and test activities are carried out to verify them.Results show the values of practical engineering approaches to the solution.Experience also contributed to avoiding future mal-operations and strengthening the reliability of the protection system,and thus of the power supply in Brazil.

Research on Testing Technology of Relay Protection for Intelligent Substations

Intelligent substations adopt various kinds of new technologies, including information sharing technology based on IEC61850, digital sampling technology, synchronization technology, and network transmission technology. Relay protection equipment faces all the challenges brought by the application of these new technologies. After analyzing the demand for test, the authors propose testing methods and technical requirements targeting the test items in great need, including ICD model file test, digital interface performance test, coordination performance test with merging unit and smart terminal, network pressure test. And the problems occurring during the tests are summarized.