Recently, the "Pure Machinery Overspeed Protection Device" designed by Dadu River Pubugou Power Plant has won the national patent for utility model (patent No. 2014 20139777.X). This is also the fifteenth patent that the factory has acquired.
The pure mechanical overspeed device set up by hydropower units is the last protection line for the protection of water turbines, which can effectively avoid the increase of unit speed or even "flying car". It uses the flying pendulum installed on the big axle. When the speed of the unit is greater than the setting value, the flying pendulum moves to switch the oil circuit and start the emergency shutdown process of the unit to shut down the guide vane and the work gate of the inlet. In the process of unit operation, once the operation task needs to be close to the large axis, it is possible to mistakenly touch the protection device, resulting in the misoperation of the pure mechanical over-speed protection device, resulting in unplanned outage of the unit, affecting the generation of the unit and being assessed by the power grid. In order to effectively solve the above problems, a protective cover of pure mechanical over-speed protection device is designed in Waterfall Power Plant, which can protect the pure mechanical over-speed protection device comprehensively and reliably, and effectively avoid accidents caused by misoperation of the device due to personnel collision or other force majeure reasons. At present, this patent has been applied in Waterfall and Shenzhen two stations with good results.