The Lianbu Power Station is the third-level power station developed by the "two reservoirs and five levels" cascade development of Xixi River. The power station dam is located in Lianbu Township, Butuo County, and the plant is located in Lianbu Township, Butuo County, about 173Km away from Xichang City. The power station is a water diversion power station with low gate and high head, with a maximum storage capacity of 2.08 million M3 and an adjustable storage capacity of 870,000 M3, with daily adjustment capacity. The low gate water diversion tunnel has a total length of 13.6Km, a rated water head of 416.9M, and a low gate installed capacity of 2×65MW. It adopts the Francis generator set produced by GM, with a designed annual power generation of 576 million KWh, and adopts the unit wiring method of single machine, single transformer and single bus. , The 220KV bus is a single bus segment wiring, the two units connected to the 220KV bus are connected to a 220KV bus, and then sent out by the Jiupu line through the Lianjiu line through the Luogu 220KV switch station.

According to Article 13.1.6 of the "25 Key Requirements of the National Energy Administration on Preventing Electric Power Production Accidents" (Guo Neng Security [2014] No. 161) The connection between the density relay and the switchgear body should meet the requirement of not disassembling the verification density relay. At present, the density relay of the SF6 circuit breaker of the basin power station does not meet the connection method and inspection conditions required by the countermeasures. It is necessary to improve the online monitoring system of the SF6 density relay of the combined water power station of the basin power station, so as to realize the requirement of online detection and verification without dismantling the density relay. . The SF6 density relays of No. 1 main transformer, No. 2 main transformer bus connection circuit breaker, Lianjiu line circuit breaker and ground connection circuit breaker of the joint-supplementary power station are equipped with combined valve-controlled joints to meet the requirements of realizing the density relay without dismantling. The requirements for verification can be checked online.

In January 2016, Weavers and China Huadian Xixihe Hydropower Development Co., Ltd. successfully signed the project of "Sichuan Huadian Xixihe Hydropower Development Co., Ltd. Basin Power Station 220kV, 10kV SF6 Circuit Breaker Density Relay Online Monitoring System Transformation" project.

The planned power outage time of the substation is March 22-24, 2016. After the contract is signed, in order not to delay the planned outage period, the company's technical service department immediately dispatched technical engineers to the site to survey and check the technical data of the equipment regardless of the peak flow of people during the Spring Festival.

The picture shows the site picture of Weavers technical engineer in the joint power station construction and SF6 density relay verification.

Weavers' online verification system for SF6 density relay is based on not changing any original structure of the switch, through the SF6 density relay interface on the switch, and adding a combined valve with a breaking device. The valve is designed with The original SF6 density relay interface is equipped with the connector, the SF6 density relay connector, the breaking device and the connector connected with the special SF6 density relay calibrator. After the connection is made according to the design requirements, the on-off of the gas circuit of the SF6 density relay and the gas circuit of the switch body can be realized by rotating the breaking device. When the SF6 density relay needs to be calibrated, it is necessary to rotate the breaking device on the valve body to the closed state, and then connect the calibrator interface with the calibration interface reserved on the valve body to complete the connection, and then the SF6 density relay can be realized. This can greatly save the precious time of maintenance personnel, and can also greatly reduce the risk of SF6 leakage caused by regular calibration and disassembly.