A power transfer system includes a first branch including a controlled switch and a second branch including a variable frequency converter, in parallel between an AC network and a reversible pump-turbine, the variable frequency converter includes: a first AC/DC converter having a first DC interface, and a second AC/DC converter having a second DC interface, the first and second DC interfaces being connected by a DC link, a control circuit having a first mode wherein it simultaneously opens the switch and it transfers electrical power until it reaches the same frequency on two AC interfaces, and having a second mode wherein it closes the switch of the first branch; an energy storage system; and a switching system for selectively connecting the energy storage system to the DC link.

The invention relates to energy generation and water conservation. There are many water systems which might lend themselves to energy extraction, such as canal systems. However, despite canal systems being around for hundreds of years, practical solutions for using the energy available have not been developed. The invention provides, among various examples, a system which can be associated with a lock in a canal and provides a flow control strategy responsive to water availability upstream of the lock. Thus electricity may be generated selectively in response to the lock state and energy demands but without adversely affecting the canal system by taking excess water. The system may be applied to multiple locks and may incorporate machine learning to evolve a strategy for a canal based on lock usage and energy demand.

The present disclosure provides a luminous water outlet device, which includes a hydroelectric power generation module, a waterway separation body, a waterway switching module, a water outlet panel, and a light board. The hydroelectric power generation module is arranged at a water inlet, the waterway separation body has two waterways, the waterway switching module is used to switch a flow of water in the two waterways, and the water outlet panel is correspondingly arranged below the two waterways, the light board is electrically connected with the hydroelectric power generation module. Compared with the prior art, the hydroelectric power generation module is arranged in the water inlet to ensure that the light board works no matter which waterway is opened and allows water to flow through. Further, the present disclosure has simpler installation, smaller volume, and simpler waterway structure.

According to an embodiment, the vane 13 has a thick root portion 16P formed on the band 12 side of a pressure surface to be joined to the band 12, with a thickness of the thick root portion 16P being gradually increased toward the band 12, and a thick root portion 16N formed on the band 12 side of a negative pressure surface to be joined to the band 12, with a thickness of the thick root portion 16N being gradually increased toward the band 12. The outlet end 15 has a first curved portion 151 and a second curved portion 152. An extreme point 15B forming a bottom end of the second curved portion 152 is positioned closer to the band 12 than an end of the thick root portion 16P, 16N on the crown 11 side.

A startup method of a Francis turbine according to an embodiment includes: a first rotation-speed increasing step in which a rotation speed of the runner is increased by opening the guide vane at a first opening; a second rotation-speed increasing step in which the increase in the rotation speed of the runner is accelerated by opening the guide vane at a second opening that is larger than the first opening after the first rotation-speed increasing step; and a rotation-speed regulating step in which the rotation speed of the runner is regulated to a rated rotation speed by opening the guide vane at a no-load opening after the second rotation-speed increasing step. The first opening is an opening that is half or less than the no-load opening.

A hydroelectric energy production and storage system comprising an upper reservoir located in a depression or cavity in the ground and a lower reservoir located underground, where objects are arranged in the depression or cavity forming an aggregate which fills the depression or cavity and comprises hydraulically communicating void volumes between the objects is disclosed. Further, a method for building and operating such a system is presented.

The present invention provides a hydraulic turbine cavitation acoustic signal identification method based on big data machine learning. According to the method, time sequence clustering based on multiple operating conditions under the multi-output condition of the hydraulic turbine set is performed by utilizing an neural network, characteristic quantities of the hydraulic turbine set under a steady condition in a healthy state is screened; a random forest algorithm is introduced to perform feature screening of multiple measuring points under steady-state operation of the hydraulic turbine set, optimal feature measuring points and optimal feature subsets are extracted, finally a health state prediction model is constructed by using gated recurrent units; whether incipient cavitation is present in the equipment is judged. The present invention can effectively identify the occurrence of incipient cavitation in the hydraulic turbine set, reducing unnecessary shutdown of the equipment and prolonging the service life.

Methods, systems and apparatuses including systems and methods that can be used for operating a hydrokinetic turbine such as along one or more flow channels of a river for power generation is disclosed. The hydrokinetic turbine can be positioned within the one or more flow channels or can be shaped to form one or more flows and can be turned by the flow of the river.

A split-type blade, a fluid drive device and a fluid drive proportional mixer. The split-type blade is used as a component of the fluid drive device to convert pressure energy of fluid into mechanical energy. The split-type blade comprises: one or more push rods, each push rod being suitable for being arranged on a rotor of the fluid drive device in a radially slidable manner; and two valve plates, the two valve plates being respectively mounted in parallel at two end portions of the push rods, and each valve plate extending outwards along the push rods to form the split-type blade having a running-through push rod structure. In this way, when the split-type blade drives the rotor to rotate under the effect of a fluid, the push rods of each split-type blade slide in a radial direction relative to the rotor.

A piston-type water hammer absorber comprising: a cylinder body, a plug assembly and a piston; wherein a receiving cavity is formed in the cylinder body, and the piston is movably blocked in the receiving cavity; one end of the cylinder body is provided with a first opening and the other end is provided with a second opening, the first opening and the second opening respectively communicate with two ends of the receiving cavity, and an end of the cylinder body corresponding to the first opening is provided with a limiting part; and the plug assembly blocks the second opening, and a sealed cavity is formed between the plug assembly and the piston.