A water level signal measurement and transmission system for a hydropower station surge tank

Abstract

The present invention relates to a hydropower station monitoring technology, which discloses a water level signal measurement and transmission system for a hydropower station surge tank, which solves the problem in the prior art that the signal cannot be collected and transmitted to a computer monitoring system and a speed regulator system due to the remote location of the surge tank. The system includes an on-site signal acquisition box arranged next to the surge tank, a water level signal acquisition module arranged in the surge tank, a computer monitoring system LCU, a host computer, a unit LCU and a speed regulator control cabinet; the water level signal acquisition module is used to collect the water level signal of the surge tank in real time and transmit it to the on-site signal acquisition box; the on-site signal acquisition box processes the water level signal and transmits the water level signal remotely to the computer monitoring system LCU; the computer monitoring system LCU uploads the water level signal to the host computer, and at the same time transmits the water level signal to each unit LCU, and each unit LCU transmits the water level signal to the corresponding speed regulator control cabinet to participate in the PID adjustment of the speed regulator.

Description

Technical Field

[0001] The invention relates to a hydropower station monitoring technology, and in particular to a hydropower station surge tank water level signal measurement and transmission system. Background Art

[0002] During the operation of a hydroelectric generator set, if an emergency occurs, causing the unit to dump load and quickly close the guide vane, a large water hammer effect will occur due to the inertia of the water flow, causing the local pressure in the water diversion pipeline to rise sharply. The setting of a surge tank can effectively reduce the water hammer effect during the transition process and reduce the damage to the unit's water inlet main valve, guide vanes, pressure pipelines and other parts during the transition process.

[0003] For economic considerations, some hydropower stations with multiple units will adopt a "one pipe, multiple units" water diversion method, that is, one water diversion pipeline is used for multiple units, and a fork pipe is set at the end of the water diversion pipeline to connect to each unit. Since the pressure regulating well is generally located in the middle of the water diversion pipeline, the location is remote and far away from the main powerhouse, so the water level signal is usually not remotely monitored in the prior art.

[0004] After research, it is found that during the transition process of hydropower station units, especially in the "one pipe multiple units" water diversion mode, the introduction of the pressure regulating well water level signal can effectively optimize the PID adjustment ability of the speed regulator and reduce the pressure fluctuation in the pressure pipeline during the transition process of the hydropower station units. In addition, it can prevent the speed regulator from malfunctioning due to the pressure oscillation in the water diversion system of other units when a single unit is dumped, causing multiple units to dump load and then causing serious fluctuations in the system.

[0005] Therefore, it is necessary for this application to propose a water level signal measurement and transmission system for the pressure regulating well of a hydropower station to realize real-time monitoring of the water level signal of the pressure regulating well, and introduce the signal into the speed regulator control cabinet to optimize the PID adjustment of the speed regulator, reduce the system oscillation during the transition process of the hydropower station unit, and improve the stability of the unit operation. Summary of the invention

[0006] The technical problem to be solved by the present invention is to propose a water level signal measurement and transmission system for a hydropower station surge tank, which solves the problem in the prior art that the signal cannot be collected and transmitted to the computer monitoring system and the speed regulator system due to the remote location of the surge tank.

[0007] The technical solution adopted by the present invention to solve the above technical problems is:

[0008] A water level signal measurement and transmission system for a surge tank in a hydropower station, comprising a local signal acquisition box arranged beside the surge tank, a water level signal acquisition module arranged in the surge tank, a computer monitoring system LCU, a host computer, a unit LCU and a speed regulator control cabinet;

[0009] The water level signal acquisition module is used to collect the water level signal of the pressure regulating well in real time and transmit it to the on-site signal acquisition box; the on-site signal acquisition box processes the water level signal and remotely transmits the water level signal to the computer monitoring system LCU; the computer monitoring system LCU uploads the water level signal to the host computer and transmits the water level signal to each unit LCU at the same time. Each unit LCU transmits the water level signal to the corresponding speed regulator control cabinet to participate in the PID adjustment of the speed regulator.

[0010] As a further optimization, the water level signal acquisition module transmits the collected water level signal to the on-site signal acquisition box via a shielded control cable between the pressure regulating well and the on-site signal acquisition box.

[0011] As a further optimization, the on-site signal acquisition box adopts a closed metal structure with a protection level not less than IP54, and includes a remote IO module, an analog input module and two switch power supply modules;

[0012] The analog input module is used to collect the water level signal from the water level signal acquisition module; the remote IO module is used to transmit the water level signal to the computer monitoring system LCU through the long-distance direct-buried armored optical cable;

[0013] The two switch power supply modules are respectively connected to different busbars of the power supply system of the hydropower station through long-distance direct-buried armored cables, and are used to provide redundant power supply for the on-site signal acquisition box.

[0014] As a further optimization, the computer monitoring system LCU uploads the water level signal to the host computer via Ethernet. The host computer displays the water level signal in real time and issues an alarm in case of abnormality.

[0015] As a further optimization, the computer monitoring system LCU transmits the water level signal to each unit LCU via Ethernet; each unit LCU is provided with an analog output module, and the analog output module is used to transmit the water level signal to the corresponding speed regulator through a shielded control cable between the corresponding speed regulator control cabinet.

[0016] As a further optimization, the water level signal acquisition module adopts a redundantly configured immersion liquid level sensor.

[0017] The beneficial effects of the present invention are:

[0018] Based on the above system, the water level signal of the pressure regulating well can be collected into the computer monitoring system of the hydropower station and the speed governor control cabinet, which not only eliminates a monitoring blind spot of the computer monitoring system of the hydropower station, but also allows the water level signal to participate in the PID adjustment of the speed governor, reducing the system oscillation during the transition process of the hydropower station unit and improving the stability of the power station unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural block diagram of the water level signal measurement and transmission system in the present invention;

[0020] Figure 2 It is a schematic diagram of collecting water level signals by the on-site signal collection box in the embodiment;

[0021] Figure 3 It is a schematic diagram of uploading water level signals and adopting redundant power supply in the local signal collection box in the embodiment;

[0022] Figure 4 It is a schematic diagram of the monitoring system in the embodiment transmitting the water level signal to the host computer and the speed regulator. DETAILED DESCRIPTION

[0023] The present invention aims to propose a water level signal measurement and transmission system for a hydropower station surge tank, which solves the problem in the prior art that the signal cannot be collected and transmitted to the computer monitoring system and the speed regulator system due to the remote location of the surge tank. The core idea is: by setting up a set of redundant surge tank water level measurement devices, and collecting the surge tank water level signal through on-site processing equipment, and then transmitting the signal to the power station computer monitoring system through an optical fiber network, the monitoring system is used to monitor the surge tank water level signal in real time, and at the same time, the signal is introduced into the speed regulator control cabinet through the monitoring system to improve the control logic of the speed regulator and improve the operating stability of each unit in the power station.

[0024] In the specific implementation, Figure 1 As shown, the water level signal measurement and transmission system of the surge tank of the hydropower station in the present invention includes: an on-site signal acquisition box, a water level signal acquisition module, a computer monitoring system LCU, a host computer, a unit LCU and a speed regulator control cabinet; the water level signal acquisition module is used to collect the water level signal of the surge tank in real time and transmit it to the on-site signal acquisition box; the on-site signal acquisition box processes the water level signal and transmits the water level signal remotely to the computer monitoring system LCU; the computer monitoring system LCU uploads the water level signal to the host computer, and at the same time transmits the water level signal to each unit LCU, and each unit LCU transmits the water level signal to the corresponding speed regulator control cabinet to participate in the PID adjustment of the speed regulator.

[0025] Among them, the water level signal is transmitted between the water level signal acquisition module and the on-site signal acquisition box through a shielded control cable. The on-site signal acquisition box transmits the water level signal to the computer monitoring system LCU through a long-distance direct-buried armored optical cable based on the internal remote IO module. The computer monitoring system LCU uses the Ethernet network of the computer monitoring system to upload this signal to the host computer in real time for real-time monitoring, and transmits this signal to each unit LCU through the Ethernet network. Each unit LCU transmits this signal to the speed regulator through a shielded control cable to participate in PID regulation.

[0026] Example:

[0027] In this embodiment, a redundant immersion water level sensor is set at the pressure regulating well to convert the pressure regulating well water level signal into a 4-20mA analog signal and transmit it through a shielded layer with a single core cross-sectional area of ​​not less than 1.0mm 2 The twisted pair control cable introduces the signal into the local signal collection box located next to the pressure regulating shaft, such as Figure 2 shown.

[0028] The on-site signal acquisition box adopts a closed metal structure with a protection level of not less than IP54. It is equipped with a remote IO module, a switching power supply, an input and output module, a relay, a terminal block, a lightning protection device, etc.; the control power supply in the on-site signal acquisition box is provided by a switching power supply, and the external power supply adopts 2-way power supply signals, which are taken from different busbars of the hydropower station's plant electricity, and redundant power supply is provided through a long-distance direct-buried armored cable, thereby ensuring the stability of the acquisition box; and the use of a switching power supply can eliminate the voltage drop caused by remote power supply.

[0029] The local signal acquisition box collects 4-20mA signals from the immersion water level sensor through the analog input module. After being processed by the local signal acquisition box, the signal is transmitted to the nearest LCU (local control unit) of the power station computer monitoring system through the optical fiber transmission channel. The two-way signal is processed and mutually verified in the LCU. The optical fiber transmission channel is realized by long-distance direct buried armored optical cable, such as Figure 3 shown.

[0030] The computer monitoring system LCU uploads this signal to the host computer in real time through the Ethernet network, displays it in real time in the central control room, and issues an alarm when the signal is abnormal. At the same time, this signal is transmitted to the LCU of each unit through the Ethernet network, and the AO module configured in the unit LCU converts the signal into a 4-20mA analog signal and transmits it to the speed regulator control cabinet to participate in the PID adjustment of the speed regulator, such as Figure 4 shown.

[0031] Therefore, through the signal transmission measurement and transmission system in this embodiment, the water level signal of the pressure regulating well can be collected to the hydropower station computer monitoring system for real-time monitoring and the speed regulator control cabinet, which can be used to optimize the speed regulator regulation performance, reduce system oscillations during the transition process of the hydropower station unit, and improve the output stability of the power station unit.

[0032] It should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A water level signal measurement and transmission system for a hydropower station surge tank, characterized in that: It includes an on-site signal acquisition box installed beside the pressure regulating well, a water level signal acquisition module installed in the pressure regulating well, a computer monitoring system LCU, a host computer, a unit LCU and a speed regulator control cabinet; The water level signal acquisition module is used to collect the water level signal of the pressure regulating well in real time, and transmit the collected water level signal to the on-site signal acquisition box through the shielded control cable between the pressure regulating well and the on-site signal acquisition box; the on-site signal acquisition box processes the water level signal and remotely transmits the water level signal to the computer monitoring system LCU; the computer monitoring system LCU uploads the water level signal to the host computer, and at the same time transmits the water level signal to each unit LCU, and each unit LCU transmits the water level signal to the corresponding speed regulator control cabinet to participate in the PID adjustment of the speed regulator; The on-site signal acquisition box adopts a closed metal structure with a protection level not less than IP54, and includes a remote IO module, an analog input module and two switch power supply modules; The analog input module is used to collect the water level signal from the water level signal acquisition module; the remote IO module is used to transmit the water level signal to the computer monitoring system LCU through the long-distance direct-buried armored optical cable; The two switch power supply modules are respectively connected to different busbars of the power supply system of the hydropower station through long-distance direct-buried armored cables, and are used to provide redundant power supply for the on-site signal acquisition box.

2. A hydropower station surge tank water level signal measurement and transmission system as claimed in claim 1, characterized in that: The computer monitoring system LCU uploads the water level signal to the host computer through the Ethernet network. The host computer displays the water level signal in real time and issues an alarm in case of abnormality.

3. A hydropower station surge tank water level signal measurement and transmission system as claimed in claim 1, characterized in that: The computer monitoring system LCU transmits the water level signal to each unit LCU via Ethernet; each unit LCU is provided with an analog output module, and the water level signal is transmitted to the corresponding speed regulator via a shielded control cable between the corresponding speed regulator control cabinet and the analog output module.

4. A hydropower station surge tank water level signal measurement and transmission system as claimed in any one of claims 1 to 3, It is characterized in that The water level signal acquisition module adopts a redundantly configured immersion type liquid level sensor.

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