Capital distribution network intelligence self-break record

In Xinjiekou District, Beijing, at 12:42:25 on April 14, a 10kV line tripped all the way, causing a power outage in some areas. At 12:43:07, except for the two high-voltage customers in the fault area, the remaining 90% of the lines were restored. It took only 35 seconds for the fault to recover power from positioning, isolation, and non-fault areas. This is the shortest time since the intelligent self-healing function of the distribution network in Beijing City was enabled.

"After a failure, we do not have to use manual remote operation. All of the action steps are completed automatically by the distribution automation system," said the on-duty dispatcher. Before the implementation of the distribution automation pilot project, if a similar fault occurs, the dispatcher must first upload the signal through various systems and the feedback information of the personnel at the accident site to analyze and judge the operation mode of the power grid, and then command the operation personnel and the repair personnel to work together. To restore power supply, the troubleshooting time should be at least 30 minutes. After the intelligent self-healing function is realized, the distribution automation system can automatically and remotely isolate the fault section to ensure that the power supply to the non-failure section is not affected, effectively avoiding long-term power outages caused by general accidents.

"The fault of the line is like a sick person. The distribution automation system is the doctor who diagnoses and cures the illness. The intelligent self-healing function is a means to isolate the source of the disease." According to Han Xuesen, a distribution automation specialist at the Beijing City Power Supply Company, the line was self-healing. The case has been shortened by more than 7 seconds since the restoration of non-faulty area power supply in 42 seconds in Guangwai Outer Region in 2012. This is due to the special vacancy work carried out by the Beijing City Power Supply Company on automation equipment, which mainly includes equipment board line upgrade, hard encryption equipment installation, etc. Through one year's efforts, the content has completed more than 700 times of defects in distribution automation terminal processing, which has played an important role in the practical application of the line's intelligent self-healing function.

Since 2005, the distribution automation in Beijing has lasted for 9 years. Currently, the distribution automation system has access to 4336 stations of various types, and the overall coverage rate has reached 58.3%. As of the end of 2013, 103 circuits in the urban area have been equipped with intelligent self-healing functions. Recently, Beijing City Power Supply Company also started the status of distribution automation equipment operation, which will reduce the defect rate of automated terminals, and further enhance the level of distribution automation management and practical.

In the next phase, Beijing City Power Supply Company will continue to focus on distribution network construction, strengthen safety, quality and schedule management, and further expand the coverage of smart self-healing functions of distribution lines. It is planned to increase the number of intelligent self-healing circuits in 2014. With 150 pieces, the ultimate goal is to improve the ability to quickly handle power grid failures and improve the reliability of distribution network power supplies.