CN-121993340-A - Overspeed protection system for hydropower station unit

CN121993340ACN 121993340 ACN121993340 ACN 121993340ACN-121993340-A

Abstract

The invention provides an overspeed protection system of a hydropower station unit, which comprises a hydraulic valve bank and a mechanical hydraulic overspeed protection device, wherein an oil input end of the hydraulic valve bank is connected with an oil output end of a proportional valve bank, an oil output end of the hydraulic valve bank is connected with a control input end of a pressure distribution valve bank, a power input end of the mechanical hydraulic overspeed protection device is connected with a power output end of a rotating shaft in the unit, an oil output end of the mechanical hydraulic overspeed protection device is connected with a control input end of the hydraulic valve bank, and the mechanical hydraulic overspeed protection device is used for stopping supplying pressure oil to the control input end of the hydraulic valve bank when the actual rotating speed of the rotating shaft in the unit exceeds a preset rotating speed so that the hydraulic valve bank cuts off a passage between the oil output end of the proportional valve bank and the control input end of the pressure distribution valve bank. In the overspeed protection system of the hydropower station unit, an electrical control system independent of the unit not only simplifies control logic and pipeline distribution, but also greatly reduces failure risk of the system.

Inventors

GUO HONGE
WU SHIHU
XU BO
YANG QIANG
LUO YOUDE
LU YUNJIANG
Mu Jielei
DING WEI
DENG YUCHEN
GU DINGHONG
WANG JI

Assignees

华能澜沧江水电股份有限公司
云南联合电力开发有限公司

Dates

Publication Date: 20260508
Application Date: 20260206

Claims (10)

1. An overspeed protection system for a hydroelectric generating set, comprising: A hydraulic control valve group and a mechanical hydraulic overspeed protection device; the hydraulic control valve unit comprises a hydraulic control valve unit, a proportional valve unit, a hydraulic control valve unit and a pressure distribution valve unit, wherein the hydraulic input end of the hydraulic control valve unit is connected with the hydraulic output end of the proportional valve unit, and the hydraulic output end of the hydraulic control valve unit is connected with the control input end of the pressure distribution valve unit; The power input end of the mechanical hydraulic overspeed protection device is connected with the power output end of the rotating shaft in the unit, the oil input end of the mechanical hydraulic overspeed protection device is filled with pressure oil, and the oil output end of the mechanical hydraulic overspeed protection device is connected with the control input end of the hydraulic control valve group; the mechanical hydraulic overspeed protection device is used for stopping supplying pressure oil to the control input end of the hydraulic control valve group when the actual rotating speed of the rotating shaft in the unit exceeds the preset rotating speed, so that the hydraulic control valve group cuts off a passage between the oil output end of the proportional valve group and the control input end of the pressure distribution valve group.
2. The hydropower station unit overspeed protection system of claim 1, wherein the hydraulic valve group comprises: The hydraulic control reversing valve is characterized in that a P port of the hydraulic control reversing valve is connected with an oil output end of the proportional valve bank, a T port of the hydraulic control reversing valve is connected with an oil tank, a B port of the hydraulic control reversing valve is connected with a control input end of the pressure distribution valve bank, and an X port of the hydraulic control reversing valve is connected with an oil output end of the mechanical hydraulic overspeed protection device; the hydraulic control reversing valve is used for conducting the P port and the B port of the hydraulic control reversing valve when the X port receives the pressure oil supplied by the mechanical hydraulic overspeed protection device, and conducting the T port and the B port of the hydraulic control reversing valve when the X port does not receive the pressure oil supplied by the mechanical hydraulic overspeed protection device.
3. The hydropower station unit overspeed protection system of claim 2, wherein the proportional valve group comprises: a first servo proportional valve and a second servo proportional valve; The hydraulic control reversing valve comprises a first servo proportional valve, a second servo proportional valve, a hydraulic control reversing valve and a hydraulic control valve, wherein the P port of the first servo proportional valve is filled with pressure oil, the T port of the first servo proportional valve is connected with an oil tank, and the A port of the first servo proportional valve is connected with the P port of the hydraulic control reversing valve; The P port of the second servo proportional valve is filled with pressure oil, the T port of the second servo proportional valve is connected with an oil tank, and the A port of the second servo proportional valve is connected with the T port of the hydraulic control reversing valve.
4. A hydropower station unit overspeed protection system according to claim 3, characterized in that the proportional valve group further comprises: The first electromagnetic directional valve is arranged between the hydraulic control directional valve and the proportional valve group, a P port of the first electromagnetic directional valve is connected with an A port of the first servo proportional valve, a T port of the first electromagnetic directional valve is connected with an A port of the second servo proportional valve, and an A port of the first electromagnetic directional valve is connected with a P port of the hydraulic control directional valve; the first electromagnetic reversing valve is used for conducting the P port and the A port of the first electromagnetic reversing valve, or conducting the T port and the A port of the first electromagnetic reversing valve.
5. The hydroelectric power generating set overspeed protection system of claim 4, wherein said system further comprises: The second electromagnetic reversing valve is arranged between the hydraulic control reversing valve and the first electromagnetic reversing valve, the P port of the second electromagnetic reversing valve is connected with the A port of the first electromagnetic reversing valve, the T port of the second electromagnetic reversing valve is connected with the oil tank, and the A port of the second electromagnetic reversing valve is connected with the P port of the hydraulic control reversing valve; The second electromagnetic reversing valve is used for conducting the P port and the A port of the second electromagnetic reversing valve, or conducting the T port and the A port of the second electromagnetic reversing valve.
6. The hydroelectric power generating set overspeed protection system of claim 5, wherein said system further comprises: the third electromagnetic reversing valve is arranged between the hydraulic control reversing valve and the second electromagnetic reversing valve, the P port of the third electromagnetic reversing valve is connected with the A port of the second electromagnetic reversing valve, the T port of the third electromagnetic reversing valve is connected with the oil tank, and the A port of the third electromagnetic reversing valve is connected with the P port of the hydraulic control reversing valve; the third electromagnetic directional valve is used for conducting the P port and the A port of the third electromagnetic directional valve, or conducting the T port and the A port of the third electromagnetic directional valve.
7. The hydroelectric power generating set overspeed protection system of claim 6, wherein said system further comprises: the hydraulic pressure integrated block, the pressure distribution valve group is arranged in the hydraulic pressure integrated block, and the hydraulic control reversing valve, the first electromagnetic reversing valve, the second electromagnetic reversing valve, the third electromagnetic reversing valve, the first servo proportional valve and the second servo proportional valve are arranged on the hydraulic pressure integrated block at intervals in sequence.
8. The hydropower station unit overspeed protection system of claim 2, wherein the mechanical hydraulic overspeed protection apparatus comprises: an overspeed detector and an overspeed valve; the power input end of the overspeed detector is connected with the power output end of the rotating shaft in the unit, and the power output end of the overspeed detector is connected with the power input end of the overspeed valve; the P port of the overspeed valve is filled with pressure oil, the A port of the overspeed valve is connected with the X port of the hydraulic control valve group, and the T port of the overspeed valve is connected with an oil tank; the overspeed valve is used for supplying pressure oil to the X port of the hydraulic control valve group when the actual rotating speed of the rotating shaft in the unit does not exceed the preset rotating speed, so that the P port and the B port of the hydraulic control reversing valve are communicated; and stopping supplying the pressure oil to the X port of the hydraulic control valve group when the actual rotation speed of the rotating shaft in the unit exceeds the preset rotation speed, so that the T port and the B port of the hydraulic control reversing valve are communicated.
9. The hydroelectric power generating set overspeed protection system of claim 1, wherein the system further comprises: The signal input end of the monitoring module is connected with the signal output end of the mechanical hydraulic overspeed protection device, and the mechanical hydraulic overspeed protection device is used for sending an early warning signal to the monitoring module when the actual rotating speed of the rotating shaft in the unit exceeds the preset rotating speed.
10. The hydroelectric power generating set overspeed protection system of claim 1, wherein the system further comprises: The oil input end of the pressure detection unit is respectively connected with the oil input end of the pressure distribution valve group and the oil input end of the proportional valve group, and the pressure detection unit is used for detecting the pressure of pressure oil.

Description

Overspeed protection system for hydropower station unit Technical Field The disclosure relates to the technical field of hydropower station speed regulator systems, in particular to an overspeed protection system of a hydropower station unit. Background The core function of the speed regulator control system is to maintain the stability of the rotation speed of the generator and the frequency of the power grid, and the speed regulator control system is a neural center and an intelligent heart of the hydropower station, and is directly related to the safety, stability, high efficiency and electric energy quality of the hydropower station. In the existing speed regulator control system, an accident pressure distribution valve is adopted for overspeed protection, but the adoption of the accident pressure distribution valve leads to complex control of the system, a plurality of pipelines are needed, and meanwhile, the closing time is required to be additionally adjusted, the current accident pressure distribution valve basically adjusts the closing time through a spring, and the closing time is prolonged and the failure risk is increased due to the change of the elasticity of the spring along with the increase of the running time. Disclosure of Invention The present disclosure aims to solve, at least to some extent, one of the technical problems in the related art. To this end, an object of the present disclosure is to provide a hydropower station unit overspeed protection system. In order to achieve the aim, the disclosure provides an overspeed protection system of a hydropower station unit, which comprises a hydraulic control valve group and a mechanical hydraulic overspeed protection device; the hydraulic control valve unit comprises a hydraulic control valve unit, a proportional valve unit, a mechanical hydraulic overspeed protection device, a hydraulic overspeed protection device and a hydraulic overspeed protection device, wherein the hydraulic input end of the hydraulic control valve unit is connected with the hydraulic output end of the proportional valve unit, the hydraulic output end of the hydraulic control valve unit is connected with the control input end of the hydraulic control valve unit, the proportional valve unit is used for controlling the hydraulic pressure of the control input end of the hydraulic control valve unit so that the hydraulic control valve unit controls the opening degree of guide vanes in the unit, the power input end of the mechanical hydraulic overspeed protection device is connected with the power output end of a rotating shaft in the unit, the hydraulic input end of the mechanical hydraulic overspeed protection device is introduced with pressure oil, the hydraulic output end of the mechanical hydraulic overspeed protection device is connected with the control input end of the hydraulic control valve unit, and the mechanical hydraulic overspeed protection device is used for stopping supplying pressure oil to the control input end of the hydraulic control valve unit when the actual rotating speed of the rotating shaft in the unit exceeds a preset rotating speed, so that the hydraulic control valve unit cuts off a passage between the hydraulic output end of the proportional valve unit and the control input end of the hydraulic control valve unit. The hydraulic control valve bank comprises a hydraulic control reversing valve, wherein a P port of the hydraulic control reversing valve is connected with an oil output end of the proportional valve bank, a T port of the hydraulic control reversing valve is connected with an oil tank, a B port of the hydraulic control reversing valve is connected with a control input end of the pressure distribution valve bank, an X port of the hydraulic control reversing valve is connected with an oil output end of the mechanical hydraulic overspeed protection device, the hydraulic control reversing valve is used for conducting the P port and the B port of the hydraulic control reversing valve when the X port receives pressure oil supplied by the mechanical hydraulic overspeed protection device, and conducting the T port and the B port of the hydraulic control reversing valve when the X port does not receive pressure oil supplied by the mechanical hydraulic overspeed protection device. The proportional valve group comprises a first servo proportional valve and a second servo proportional valve, wherein the P port of the first servo proportional valve is filled with pressure oil, the T port of the first servo proportional valve is connected with an oil tank, the A port of the first servo proportional valve is connected with the P port of the hydraulic control reversing valve, the P port of the second servo proportional valve is filled with pressure oil, the T port of the second servo proportional valve is connected with the oil tank, and the A port of the second servo proportional valve is connected with the T port of the hydraulic control reversing