CN-122014478-A - Variable-speed water pump turbine unit, adjusting and controlling vibration-proof device and method

CN122014478ACN 122014478 ACN122014478 ACN 122014478ACN-122014478-A

Abstract

The application provides a variable-speed water pump turbine unit, a regulating and vibration-preventing device and a regulating and vibration-preventing method. The device comprises a plurality of connecting key mechanisms, wherein the connecting key mechanisms comprise connecting key bodies and pretightening force applying units, the connecting key bodies are arranged between the adjacent two rib plates and are used for being connected with the side surfaces of the adjacent two rib plates, and the pretightening force applying units are integrated with or act on the connecting key bodies and are used for applying controllable axial pretightening force to the connecting key bodies so as to adjust the overall rigidity of the unit and change the natural frequency of the unit. The rotating frequency of the machine set can effectively avoid the natural frequency of the fixed component in the whole variable speed operation range of the machine set, and resonance is fundamentally restrained.

Inventors

WANG ZHENGWEI
YANG XIAOLONG
GAO YANMING
LIN KAI
LIU TAO
CHEN HONGYU
ZHANG GUANGSHENG

Assignees

清华大学
南方电网调峰调频发电有限公司工程建设管理分公司
广州启安众智建设管理有限责任公司

Dates

Publication Date: 20260512
Application Date: 20260324

Claims (10)

1. The utility model provides a device that shakes is kept away in regulation and control of variable speed water pump turbine unit, its characterized in that, the unit includes down ring, seat ring and top cap, down the ring include annular plate and along circumference evenly distributed in a plurality of radial gusset of annular plate, adjacent two form the cavity between the gusset, the device includes: The connecting key mechanism comprises a connecting key body and a pretightening force applying unit, wherein the connecting key body is arranged between two adjacent rib plates and is used for being connected with the side faces of the two adjacent rib plates, and the pretightening force applying unit is integrated with or acts on the connecting key body and is used for applying controllable axial pretightening force to the connecting key body so as to adjust the overall rigidity of the unit and further change the natural frequency of the unit.
2. The apparatus as recited in claim 1, further comprising: The vibration sensor is arranged on at least one of the lower ring, the seat ring and the top cover and is used for monitoring vibration data of the unit, wherein the vibration data comprise vibration amplitude and vibration frequency; the rotating speed monitoring unit is used for monitoring the current running rotating speed of the unit; The controller is electrically connected with the vibration sensor, the rotating speed monitoring units and the pretightening force applying units, and is used for judging whether the running state of the unit meets the regulation requirement or not according to the signals of the vibration sensor and the rotating speed monitoring units, calculating the rigidity variation required by the unit when the running state of the unit meets the regulation requirement, generating a control instruction and sending the control instruction to the pretightening force applying units, and controlling the pretightening force applying units to regulate the pretightening force output by the pretightening force applying units so as to regulate the integral rigidity of the unit, thereby changing the natural frequency of the unit.
3. The apparatus of claim 2, wherein the adjustment requirement comprises at least one of: the vibration amplitude and frequency of the unit exceed the safety threshold; the difference value between the current rotating frequency of the unit and the natural frequency of the unit is within a set range.
4. The apparatus according to claim 2, wherein the controller includes a storage unit storing a map of an operation rotational speed and a prestress of the unit, and the controller determines the prestress corresponding to the current rotational speed of the unit according to the map, thereby calculating the stiffness variation required for the unit.
5. The device according to claim 1, wherein the two ends of the connecting key body are provided with connecting parts, and the connecting parts are fixedly connected with the rib plates through bolts, pin shafts or welding.
6. The device according to claim 1, wherein the pretension applying unit comprises a hydraulic tensioner, a piezoceramic actuator or a servo-electric cylinder, and/or The annular plate is provided with a limiting hole, and one end of the pretightening force applying unit is arranged in the limiting hole.
7. A variable speed water pump turbine unit comprising: the device comprises a lower ring, a seat ring and a top cover, wherein the lower ring comprises an annular plate and a plurality of radial rib plates uniformly distributed on the annular plate along the circumferential direction, and a cavity is formed between two adjacent rib plates; A regulatory vibration damping device according to any one of claims 1-6.
8. A method of regulating and damping a variable speed water pump turbine unit as claimed in claim 7, comprising: obtaining vibration data and current running rotating speed of a unit, wherein the vibration data comprise vibration amplitude and vibration frequency; Judging whether the running state of the unit meets the regulation requirement according to the vibration data and the current running rotating speed, calculating the rigidity variation required by the unit when the running state of the unit meets the regulation requirement, generating a control instruction, sending the control instruction to the pretightening force applying unit, and controlling the pretightening force applying unit to regulate the pretightening force output by the pretightening force applying unit so as to regulate the integral rigidity of the unit, thereby changing the natural frequency of the unit.
9. The method of claim 8, wherein the adjustment requirement comprises at least one of: the vibration amplitude and frequency of the unit exceed the safety threshold; the difference value between the current rotating frequency of the unit and the natural frequency of the unit is within a set range.
10. The method of claim 8, wherein calculating the stiffness variation required by the unit includes determining a pre-stress corresponding to a current rotational speed of the unit according to a pre-set mapping table of rotational speeds of the unit and the pre-stress, thereby calculating the stiffness variation required by the unit.

Description

Variable-speed water pump turbine unit, adjusting and controlling vibration-proof device and method Technical Field The application relates to the technical field of hydraulic mechanical vibration and control, in particular to a variable-speed water pump turbine unit, a device and a method for regulating and controlling vibration. Background The water pump and water turbine set, especially the modern variable-speed pumped storage set, can flexibly adjust the rotating speed according to the power grid demand, thereby optimizing the operation efficiency and enhancing the power grid stability. However, variable speed operation presents new challenges in that changes in the rotational speed of the unit mean that the rotational frequency (e.g., rotational frequency, lobe frequency) is also constantly changing. The natural frequency of the unit fixing components (such as a seat ring, a volute, a lower ring and the like) is very easy to coincide, serious structural resonance is caused, the unit vibration exceeds standard, the components are fatigued and damaged, and the safety of a power station is even threatened. The traditional vibration reduction method mostly adopts passive design, for example, the natural frequency and the excitation frequency under the rated rotation speed are staggered as much as possible through structural optimization in the design stage, or a damper is additionally arranged. However, these methods cannot be adapted to the conditions where the rotational speed varies widely. Once the unit is operated at variable speed, the original frequency 'safe area' is not existed, and the resonance risk is greatly increased. Therefore, there is a need for a device that can actively, in real time, adapt to rotational speed changes and dynamically adjust structural dynamics to avoid resonance. Disclosure of Invention The application aims to overcome the defects of the prior art and provides a variable-speed water pump turbine unit, a regulating and vibration-avoiding device and a regulating and vibration-avoiding method. The device can dynamically adjust the integral rigidity of the lower ring and the fixed parts connected with the lower ring on line, thereby changing the natural frequency of the lower ring, ensuring that the rotation frequency of the lower ring can effectively avoid the natural frequency of the fixed parts in the whole variable speed operation range of the unit, and fundamentally inhibiting resonance. In a first aspect, an embodiment of the present application provides a device for adjusting and damping a variable speed water pump turbine unit, where the unit includes a lower ring, a seat ring and a top cover, the lower ring includes an annular plate and a plurality of radial rib plates uniformly distributed on the annular plate along a circumferential direction, and a cavity is formed between two adjacent rib plates, and the device includes: The connecting key mechanism comprises a connecting key body and a pretightening force applying unit, wherein the connecting key body is arranged between two adjacent rib plates and is used for being connected with the side faces of the two adjacent rib plates, and the pretightening force applying unit is integrated with or acts on the connecting key body and is used for applying controllable axial pretightening force to the connecting key body so as to adjust the overall rigidity of the unit and further change the natural frequency of the unit. Optionally, the method further comprises: The vibration sensor is arranged on at least one of the lower ring, the seat ring and the top cover and is used for monitoring vibration data of the unit, wherein the vibration data comprise vibration amplitude and vibration frequency; the rotating speed monitoring unit is used for monitoring the current running rotating speed of the unit; The controller is electrically connected with the vibration sensor, the rotating speed monitoring units and the pretightening force applying units, and is used for judging whether the running state of the unit meets the regulation requirement or not according to the signals of the vibration sensor and the rotating speed monitoring units, calculating the rigidity variation required by the unit when the running state of the unit meets the regulation requirement, generating a control instruction and sending the control instruction to the pretightening force applying units, and controlling the pretightening force applying units to regulate the pretightening force output by the pretightening force applying units so as to regulate the integral rigidity of the unit, thereby changing the natural frequency of the unit. Optionally, the adjustment requirement includes at least one of: the vibration amplitude and frequency of the unit exceed the safety threshold; the difference value between the current rotating frequency of the unit and the natural frequency of the unit is within a set range. Optionally, the controller includes a storage