The application of relays is quite extensive. In the power system, when the power system itself fails and endangers the safe operation of the power system, the relay protection device can issue a warning signal in time, or issue a trip command directly to the controlled circuit breaker to terminate the development of the fault. Reduce the damage to the power system components themselves and also meet certain specific requirements of the power system. Therefore, relay protection is called the first line of defense for the safe operation of the power grid.
However, the security and rapidity of power protection control are difficult to take into consideration. It has always been a worldwide problem that threatens the security of power grids. The two large-scale blackouts that occurred in the United States were caused by relays; in China, before the 1990s, more than half of blackouts were caused by relay protection defects.
According to the academician of the Chinese Academy of Engineering and Professor Yang Qixun of North China Electric Power University, the development of power grids and the application of new technologies for power grids have promoted the development of relay protection technologies, and have also increased the complexity of relay protection technologies and applied traditional relay protection methods. The management approach presents greater challenges. The rapid increase of short-circuit current level requires a higher speed of relay protection; the application of DC transmission and series compensation technology requires a technical breakthrough in relay protection; compact lines, multi-circuit lines on the same pole, and short-circuit lines in cities with high voltage The emergence of a large number of them makes the configuration, setting and cooperation of relay protection more complicated. The development of power grid equipment and operation control technologies, such as digital substation research, application of unattended substations, and construction and operation of UHV power grids, will impose higher requirements on the technical performance of relay protection. It is necessary to study and propose new relays. Protection solution. The actual operation of the power grid and lessons learned from domestic and foreign power grid accidents indicate that failure of a single component of a single relay protection device or device may lead to power grid accidents, and the reliability of relay protection equipment still needs to be further improved.
UHV power grids have distinct features that distinguish them from ultra-high voltage power grids. At present, there are many technical difficulties in relay protection, such as the influence of capacitive currents on the protection characteristics of ultra-high voltage lines, the influence of submergence currents on reclosing, and UHV Relay protection equipment such as electromagnetic compatibility. It is understood that at present China's relevant agencies have carried out a series of independent research and development work, and have achieved initial results.
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Type:
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Size:
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Material:
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Finish:
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Samples
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MOQ:
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