CN116698137A - Low-head power station concrete volute flow measurement system - Google Patents

Abstract

The application discloses a low-head power station concrete volute flow measuring system, which comprises a remote system, a control system and a control system, wherein the remote system comprises a circuit breaker module, an operation controller connected with the circuit breaker module, and a monitoring terminal connected with the operation controller; the acquisition system comprises a signal acquisition module, a plurality of groups of flow rate sensors and a water level sensor, wherein the signal acquisition module is in wireless connection with the operation controller, the plurality of groups of flow rate sensors are connected with the signal acquisition module, and the water level sensor is connected with the signal acquisition module; the hoisting device is arranged at the water inlet access door slot of the hydropower station and used for controlling the position change of the plurality of groups of sensors. The application has the beneficial effects that the technical problem of flow measurement of the volute of the low-head high-flow unit is solved, the working stability and the reliability of the flow measurement are obviously improved compared with the traditional differential pressure flow measurement, and the flow measurement precision is superior to that of the existing differential pressure flow measurement. The system has lower construction cost, the equipment is easy to manufacture and install, the flow rate sensor is cheaper than the currently used differential pressure measurement sensor, and the data processing system can utilize the existing computer monitoring system hardware equipment. The installation and maintenance are convenient, and because the access door slot is in an idle state when the unit normally operates, the equipment of the measuring system is easy to install and overhaul.

Description

Low-head power station concrete volute flow measurement system

Technical Field

The application relates to the technical field of hydroelectric generation, in particular to a system for measuring the flow of a concrete volute of a low-head power station.

Background

In the field of hydroelectric generation, low-head high-flow hydroelectric generating sets are widely distributed in large rivers in China, and the type of generating sets generally adopt a concrete volute type, and are characterized by large flow channel inlet sectional area, low flow velocity and large flow. The accurate measurement of the flow for generating electricity of a unit is always a technical problem puzzling the type of power station, and the current measurement mode is to arrange two groups of measurement pipelines on the concrete wall of a volute at a certain interval, and indirectly measure the flow of the volute by utilizing the Bernoulli equation of fluid and the geometric dimension of the volute through the pressure difference of the two groups of pressure measurement pipelines. In actual operation, this measurement method has the following drawbacks:

1. the pressure measuring pipeline is easy to be blocked in the running process, especially in hydropower stations with poor water quality, so that the differential pressure measuring sensor cannot work normally.

2. The low-head high-flow concrete volute type unit is low in water flow speed, the differential pressure measured value is low after passing through a long pressure measuring pipeline, the requirement on the detection precision of a differential pressure flow measuring sensor is high, and the precision cannot be achieved by a plurality of sensors at present.

3. The measuring system is difficult to arrange, the pressure measuring pipeline needs to be pre-buried, and in order to prevent pipeline damage, the standby pressure measuring pipeline is often needed, and the engineering cost is high.

Disclosure of Invention

This section is intended to outline some aspects of embodiments of the application and to briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section as well as in the description of the application and in the title of the application, which may not be used to limit the scope of the application.

The present application has been made in view of the above-mentioned or existing problems occurring in the prior art.

Therefore, the application aims to provide a low-head power station concrete volute flow measurement system which can collect information through a hoisting device control sensor arranged at a water inlet and access door slot of a hydropower station and can early warn in time after the information is processed and displayed in real time.

In order to solve the technical problems, the application provides the following technical scheme: the system comprises a remote system, a circuit breaker module, an operation controller connected with the circuit breaker module and a monitoring terminal connected with the operation controller;

the acquisition system comprises a signal acquisition module, a plurality of groups of flow rate sensors and a water level sensor, wherein the signal acquisition module is in wireless connection with the operation controller, the plurality of groups of flow rate sensors are connected with the signal acquisition module, and the water level sensor is connected with the signal acquisition module;

the hoisting device is arranged at the water inlet access door slot of the hydropower station and used for controlling the position change of the plurality of groups of sensors.

As a preferred scheme of the low head power station concrete volute flow measurement system of the application, wherein: the remote system also comprises a display module, a warning module and an output module which are connected with the monitoring terminal; the warning module comprises a warning lamp; the output module includes a printer.

As a preferred scheme of the low head power station concrete volute flow measurement system of the application, wherein: the acquisition system also comprises a temperature sensor and a pressure sensor which are connected with the signal acquisition module; the temperature sensor, the pressure sensor and the liquid level sensor are respectively used for measuring temperature and pressure data and transmitting the temperature and pressure data to the operation controller through the signal acquisition module so as to assist a worker in judging the water flow condition.

As a preferred scheme of the low head power station concrete volute flow measurement system of the application, wherein: the system also comprises a signal conversion module connected with the flow rate sensor; the acquisition system is provided with a flow velocity sensor for measuring the flow velocity of the inlet section; a water level sensor is arranged for measuring the water depth of the flow velocity measuring position of the section of the inlet; each sensor is converted into a 4-20mA signal after passing through the pre-signal conversion module and is input into the signal acquisition module, and the operation controller acquires real-time data from the signal acquisition module.

As a preferred scheme of the low head power station concrete volute flow measurement system of the application, wherein: the monitoring terminal comprises a computer; the display module comprises an external display screen.

As a preferred scheme of the low head power station concrete volute flow measurement system of the application, wherein: the operation controller receives the real-time data and transmits the real-time data to the monitoring terminal, and the monitoring terminal processes the data and displays the data in real time through the display module.

As a preferred scheme of the low head power station concrete volute flow measurement system of the application, wherein: when the flow velocity data and the water level data processed by the monitoring terminal reach the range of the preset warning value, the monitoring terminal gives an early warning through the warning module.

As a preferred scheme of the low head power station concrete volute flow measurement system of the application, wherein: the breaker module comprises a mounting frame unit and a breaker; the mounting frame unit comprises a hollow base component, a movable supporting plate component movably inserted with the hollow base component, a lifting table component arranged at one end of the hollow base component, and a positioning clamping component which is in limit connection with the lifting table component and is partially arranged in the movable supporting plate component.

As a preferred scheme of the low head power station concrete volute flow measurement system of the application, wherein: the hollow base component comprises a hollow wire holder, a wire connection port arranged above the hollow wire holder, a limiting monorail arranged at one end of the middle part of the hollow wire holder, a stop plate arranged at one end of the hollow wire holder, and a spring connected with the inner wall of the stop plate and the outer wall of the movable supporting plate component; the movable supporting plate component comprises a top moving plate arranged at one end of the movable supporting plate component, a panel connected with one side of the top moving plate, and four groups of limiting supporting plates arranged at one side of the panel along the vertical direction in an array manner; a positioning support space is formed between the two groups of positioning support plates; the lifting platform assembly comprises limit double rails symmetrically arranged, four groups of bearing plates arranged on the outer sides of the limit double rails along the vertical direction in an array mode, arc-shaped positioning grooves arranged on the bearing plates, and through lifting openings arranged on the inner sides of the bearing plates.

As a preferred scheme of the low head power station concrete volute flow measurement system of the application, wherein: the positioning clamping assembly comprises a threaded mounting plate, a threaded rod, a supporting rotating head, a stopping disc, a conical top, a connecting plate, a positioning plugboard, a double-layer clamping piece and an elastic fastener, wherein the two ends of the threaded mounting plate are in threaded connection with the limiting double-rail limiting plug, the threaded rod is in threaded connection with the threaded mounting plate, the supporting rotating head is arranged at one end of the threaded rod, the stopping disc is fixedly connected with the other end of the threaded rod, the conical top is connected with the stopping disc and the wide diameter of the conical top is from large to small, the connecting plate is arranged at one side of the threaded mounting plate, the positioning plugboard is connected with the tail end of the connecting plate, the double-layer clamping piece is arranged at one end of the positioning plugboard, is in contact with the conical top and is in plug connection with the positioning plugboard, and the elastic fastener is arranged at one end of the positioning plugboard and is in plug connection with the positioning plugboard.

The application has the beneficial effects that: the application solves the technical problem of flow measurement of the volute of the low-head high-flow unit, and compared with the traditional differential pressure flow measurement, the working stability and reliability are obviously improved, and the flow measurement precision is superior to the existing differential pressure flow measurement. The system has lower construction cost, the equipment is easy to manufacture and install, the flow rate sensor is cheaper than the currently used differential pressure measurement sensor, and the data processing system can utilize the existing computer monitoring system hardware equipment. The installation and maintenance are convenient, and because the access door slot is in an idle state when the unit normally operates, the equipment of the measuring system is easy to install and overhaul.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the description of the embodiments will be briefly described below, it being obvious that the drawings in the following description are only some embodiments of the present application, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art. Wherein:

fig. 1 is a schematic diagram of a first implementation of a low head power station concrete volute flow measurement system.

Fig. 2 is a simplified schematic diagram of a first embodiment of a low head power station concrete volute flow measurement system.

Fig. 3 is a schematic diagram of a second implementation of a low head power station concrete volute flow measurement system.

Fig. 4 is a schematic diagram of a third implementation of a low head power station concrete volute flow measurement system.

Fig. 5 is a schematic diagram showing the front view of the structure of the mounting frame unit of the low-head power station concrete volute flow measurement system.

Fig. 6 is a schematic side view of the structure of the mounting frame unit of the low head power station concrete volute flow measurement system.

Fig. 7 is a schematic top view of the structure of the mounting frame unit of the low head power station concrete volute flow measurement system.

Fig. 8 is a schematic structural diagram of a hoisting device for the method for measuring the flow of the concrete volute of the low-head power station.

Fig. 9 is a measurement schematic diagram of a low head power station concrete volute flow measurement method.

Fig. 10 is a flow diagram of a method for measuring the flow of the concrete volute of the low-head power station.

Detailed Description

In order that the above-recited objects, features and advantages of the present application will become more readily apparent, a more particular description of the application will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application, but the present application may be practiced in other ways other than those described herein, and persons skilled in the art will readily appreciate that the present application is not limited to the specific embodiments disclosed below.

Further, reference herein to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic can be included in at least one implementation of the application. The appearances of the phrase "in one embodiment" in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments.

Example 1

Referring to fig. 1 to 4, in a first embodiment of the present application, a low head power station concrete volute flow measurement system is provided, which can collect information through a control sensor of a lifting device installed at a water inlet access door slot of a hydropower station, and timely early warning after real-time processing and display of the information.

Specifically, the remote system 1 comprises a breaker module 10, an operation controller 11 connected with the breaker module 10, and a monitoring terminal 12 connected with the operation controller 11;

the acquisition system 2 comprises a signal acquisition module 20 which is in wireless connection with the operation controller 11, a plurality of groups of flow rate sensors 21 which are connected with the signal acquisition module 20, and a water level sensor 22 which is connected with the signal acquisition module 20;

and the hoisting device 3 is arranged at the water inlet access door slot of the hydropower station and used for controlling the position change of the plurality of groups of sensors.

Further, the remote system 1 further includes a display module 13, a warning module 14 and an output module 15 connected to the monitor terminal 12; the warning module 14 includes a warning lamp 141; the output module 15 includes a printer 151. The measured data can be printed and saved by the printer 151, so that the subsequent reference is facilitated.

Further, the acquisition system 2 further comprises a temperature sensor and a pressure sensor connected with the signal acquisition module 20; the temperature sensor, the pressure sensor and the liquid level sensor are respectively used for measuring temperature and pressure data and transmitting the data to the operation controller 11 through the signal acquisition module 20 so as to assist a worker in judging the water flow condition.

Further, the monitor terminal 12 includes a computer 121; the display module 13 comprises an external display screen 131; protection of the power supply lines and electrical equipment is carried out at the remote system 1 by means of the breaker module 10, which automatically breaks the circuit when they are subjected to severe overload or short-circuit or under-voltage faults.

Further, the acquisition system 2 further comprises a signal conversion module 23 connected to the flow rate sensor 21.

It should be noted that in this embodiment, each device and module may be implemented by using the existing technology, and only the necessary energy supply needs to be provided. If the lifting device 3 can adopt the existing lifting device, the lifting device is used for controlling the position change of a plurality of groups of sensors, and is convenient for measurement. The breaker module 10 includes a mounting frame unit 100 and a breaker, and in this embodiment, the breaker module 10 may use an existing switchgear cabinet frame and a breaker installed in the switchgear cabinet frame, for wiring with a power source or an electrical device, so as to play a role of protection.

The working principle of the system is as follows: the acquisition system 2 is provided with a flow rate sensor 21 for measuring the flow rate of the inlet section; the water level sensor 22 is used for measuring the water depth of an inlet section flow velocity measuring position; each sensor is converted into a 4-20mA signal through the front signal conversion module 23 and then is input into the signal acquisition module 20, and the operation controller 11 acquires real-time data from the signal acquisition module 20. The arithmetic controller 11 receives real-time data and transmits the data to the monitor terminal 12, and the monitor terminal 12 processes the data and displays the data in real time through the display module 13. When the flow rate data and the water level data processed by the monitoring terminal 12 reach the range of the preset warning value, the monitoring terminal 12 will be warned by the warning module 14.

In conclusion, the application solves the technical problem of flow measurement of the volute of the low-head high-flow unit, and compared with the traditional differential pressure flow measurement, the working stability and reliability are obviously improved, and the flow measurement precision is superior to that of the existing differential pressure flow measurement. The system has lower construction cost, the equipment is easy to manufacture and install, the flow rate sensor is cheaper than the currently used differential pressure measurement sensor, and the data processing system can utilize the existing computer monitoring system hardware equipment. The installation and maintenance are convenient, and because the access door slot is in an idle state when the unit normally operates, the equipment of the measuring system is easy to install and overhaul.

Example 2

Referring to fig. 5 to 7, for the second embodiment of the present application, a specific structure of the mounting frame unit 100 is provided, and the rest is the same as embodiment 1, which can rapidly fix and flexibly adjust the height of the circuit breaker simply by adjusting the threaded rod, and maintain locking of the adjusted height.

Specifically, the mounting frame unit 100 includes a hollow base component 101, a movable supporting plate component 102 movably inserted with the hollow base component 101, a lifting table component 103 disposed at one end of the hollow base component 101, and a positioning clamping component 104 in limited connection with the lifting table component 103 and partially disposed in the movable supporting plate component 102.

Further, the hollow base component 101 includes a hollow wire holder 101a, a wire connection port 101b disposed above the hollow wire holder 101a, a limit monorail 101c disposed at one end of the middle of the hollow wire holder 101a, a stop plate 101d disposed at one end of the hollow wire holder 101a, and a spring 101e connected to the inner wall of the stop plate 101d and to the outer wall of the movable supporting plate component 102;

and a hollow clamping groove is formed in the limiting monorail 101 c.

Further, the movable supporting plate assembly 102 includes a top moving plate 102a disposed at one end thereof, a panel 102b connected to one side of the top moving plate 102a, and four sets of limiting supporting plates 102c disposed at one side of the panel 102b in an array along a vertical direction;

a positioning support space M is formed between the two groups of limit support plates 102c;

the bottom of the panel 102b is provided with a limit moving block which is clamped with the groove of the hollow base component 101.

Further, the lifting platform assembly 103 includes a limit double rail 103a symmetrically arranged, four groups of bearing plates 103b arranged on the outer side of the limit double rail 103a along the vertical direction in an array manner, an arc-shaped positioning groove 103c arranged on the bearing plate 103b, and a through lifting opening 103d arranged on the inner side of the bearing plate 103 b;

a hollow clamping groove is formed in the limiting double rail 103 a.

Further, the positioning clamping assembly 104 comprises a threaded mounting plate 104a with two ends in limiting insertion connection with the limiting double rails 103a, a threaded rod 104b in threaded connection with the threaded mounting plate 104a, a supporting rotary head 104c arranged at one end of the threaded rod 104b, a stopping disc 104d fixedly connected with the other end of the threaded rod 104b, a conical top 104e connected with the stopping disc 104d and having a wide diameter ranging from large to small, a connecting plate 104f arranged at one side of the threaded mounting plate 104a, a positioning inserting plate 104g connected with the tail end of the connecting plate 104f, a double-layer clamping piece 104h arranged at one end of the positioning inserting plate 104g, in contact with the conical top 104e and in insertion connection with the positioning inserting plate 104g, and an elastic fastening piece 104i arranged at one end of the positioning inserting plate 104g and in insertion connection with the positioning inserting plate 104 g.

Further, the double-layer clamping member 104h includes a bevel short plate 104h-1 contacting the tapered surface of the tapered plug 104e, and a first clamping plate 104h-2 connected to the bevel short plate 104 h-1; the bottom of the bevel shortboard 104h-1 and the first clamping board 104h-2 are provided with a connected cooperating board and thus are movable together.

The elastic fastener 104i comprises a second clamping plate 104i-1, a fixed plate 104i-2 and a tightening damping spring 104i-3, wherein the bottom of the second clamping plate 104i-1 is movably connected with the positioning plugboard 104g, the fixed plate 104i-2 is fixedly connected with one end of the positioning plugboard 104g, and the tightening damping spring 104i-3 is respectively connected with the second clamping plate 104i-1 and the fixed plate 104 i-2;

the inner walls of the first clamping plate 104h-2 and the second clamping plate 104i-1 are provided with friction layers, so that the stability during clamping can be improved by arranging the friction layers, and the shapes of the first clamping plate 104h-2 and the second clamping plate 104i-1 are shown only as schematic, and can be adaptively modified according to the requirements.

Preferably, a clamping block in limit insertion connection with the limit monorail 101c is arranged at one end of the positioning insertion plate 104 g. T-shaped blocks which are inserted into the T-shaped grooves of the positioning plugboard 104gT are arranged at the bottoms of the double-layer clamping piece 104h and the second clamping plate 104 i-1. The arc-shaped positioning groove 103c is matched with the diameter of the supporting rotary head 104 c. The height of the positioning plugboard 104g is matched with the height of the positioning supporting space M.

It should be noted that, the threaded mounting plate 104a is provided with a threaded opening that is screwed with the threaded rod 104b, so that the threaded rod 104b can be screwed into or out of the threaded mounting plate 104a and kept stable. Because the inclined short plate 104h-1 contacts the conical surface of the conical plug 104e, when the conical plug 104e is screwed in, the double-layer clamping piece 104h can be pushed by the conical plug 104e to approach the elastic fastener 104i to clamp the circuit breaker inwards because the diameter of the conical plug 104e when contacting the inclined short plate 104h-1 gradually becomes larger. And because the threaded rod 104b at one end of the conical plug 104e is connected with the threaded mounting plate 104a, the transverse position is not changed, so when the contact diameter of the conical plug 104e and the inclined short plate 104h-1 reaches the maximum, the first clamping plate 104h-2 is in close contact with the circuit breaker, the jacking damping spring 104i-3 of the elastic fastener 104i is compressed to the maximum and elastically clamps the circuit breaker, and the circuit breaker is fixed. Because the diameter of the stopping plate 104d is the same as the maximum diameter of the conical plug 104e, when the threaded rod 104b continues to rotate in, the stopping plate 104d and the inclined short plate 104h-1 can still keep the clamping force unchanged, and the damage to the circuit breaker due to the excessive clamping force is avoided. The diameters of the stopper 104d and the tapered plug 104e can be adaptively adjusted as required, and thus are not described in detail.

When the circuit breaker is used, the use process is divided into two steps, wherein the first step is to fix the circuit breaker quickly, and the second step is to adjust the height of the circuit breaker after the circuit breaker is clamped so as to adapt to the installation space and the installation requirement.

When the circuit breaker is fixed, the circuit breaker can be clamped and kept with proper clamping force only by controlling the threaded rod 104b without complicated steps. First, a worker simply positions the circuit breaker between the first clamping plate 104h-2 and the second clamping plate 104i-1, and then manually controls the threaded mounting plate 104a to remain stable and rotates the threaded rod 104b. The threaded rod 104b is gradually screwed into the threaded mounting plate 104a and gradually increases the diameter of the tapered plug 104e as it contacts the beveled stub 104h-1, eventually causing the double-layered clamp 104h to push the circuit breaker into movement and into close apposition with the elastic fastener 104i, the circuit breaker is clamped, and since the threaded rod 104b is a rigid rod, the double-layered clamp 104h cannot come and go and remain stable. At this time, the supporting swivel 104c is stopped at the edge of the arc-shaped positioning groove 103c of the bearing plate 103b, and the arc-shaped positioning groove 103c supports and locks the positioning clamping assembly 104 to prevent falling; since the positioning and clamping assembly 104 is initially arranged in the positioning and supporting space M, the upper and lower sets of positioning and supporting plates 102c longitudinally limit the positioning plugboard 104g of the positioning and clamping assembly 104; the limiting double rail 103a laterally limits the threaded mounting plate 104a of the adjustment clamp assembly 104, thereby ensuring the stability of the circuit breaker after being clamped.

When the height of the circuit breaker needs to be adjusted, the threaded rod 104b is continuously screwed in only when the threaded mounting plate 104a is manually controlled, the supporting rotary head 104c is separated from the bearing plate 103b and gradually moves to the position of the through lifting opening 103d, the stopping plate 104d is contacted with the inclined short plate 104h-1, the displacement distance of the double-layer clamping piece 104h is kept unchanged, and the circuit breaker is prevented from being damaged by increasing the clamping force. The tapered plug 104e will contact the top travel plate 102a as it continues to move and displace the top travel plate 102a when it is against by the tapered plug 104e, the panel 102b will gradually approach the stop plate 101d and cause the spring 101e to be compressed with a tendency to rebound. The outer movement of the panel 102b will make the four groups of positioning support plates 102c at one side of the panel break away from contact with the positioning clamping assembly 104, when the threaded rod 104b is screwed into the maximum, the positioning clamping assembly 104 is completely separated from the positioning support space M, and the positioning clamping assembly 104 can be controlled to move up and down to a proper height along the length direction of the positioning double rail 103a, so that the functions of moisture prevention, space utilization, wire adaptation and the like can be achieved in practical application. After the height is adjusted to a proper height, the supporting rotary head 104c is screwed into the arc-shaped positioning groove 103c to be supported and locked by only reversely rotating the threaded rod 104b, and the positioning plugboard 104g enters the positioning supporting space M with different heights again to complete the height adjustment. When the threaded rod 104b is adjusted, the whole limit double rail 103a of the installation threaded rod 104b is positioned towards the outside, so that a worker does not need to operate in a narrow switch cabinet space, and adjustment and maintenance and replacement of the circuit breaker are facilitated.

In conclusion, the application does not need to be deeply penetrated into a narrow space by a worker to install and allocate, and can quickly install the circuit breaker and adjust the height position of the fixed circuit breaker only by adjusting the threaded rod arranged on the outer side; when the circuit breaker is fixed, different screws are not needed, and the circuit breaker can be clamped and fixed by rotating a single threaded rod, so that the circuit breaker can be quickly arranged on the bracket, and the disassembly and the assembly are quick and convenient; when the height position of the circuit breaker is adjusted, the double locking of the height of the circuit breaker can be unlocked under the condition that the clamping force of the circuit breaker is kept unchanged by continuously rotating the threaded rod, and the double locking can be recovered by rotating the threaded rod again after the height is adjusted according to the requirement, so that the stability in use is ensured.

Example 3

Referring to fig. 1 and 8 to 10, a third embodiment of the present application provides a method for measuring the flow rate of a concrete volute of a low-head power station, which can facilitate measurement and calculation, and realize accurate measurement of the flow rate of an inlet section.

The method utilizes a hydropower station water inlet access door slot to manufacture a bracket type volute water inlet flow velocity measuring system. The measuring system consists of a cross beam, a gate slot guide wheel, a propeller type flow velocity sensor, a water level sensor, a fixed bracket, a connecting wire and an acquisition and processing module. The acquisition module is internally provided with a water depth-flow velocity curve cluster which is fitted in advance through a test, during normal operation, a measuring system sensor is positioned on the transverse central axis of the rectangular section of the volute inlet, the flow and the water level of five points of the transverse central axis (the number of measuring points can be selected according to the size of the section of the inlet) are acquired in real time, the acquisition module selects a calculating water depth-flow velocity curve cluster according to the measured flow velocity of the central point, the section flow of each block is calculated by utilizing a speed-area method, and the total flow QΣ=Q1+Q2+ … QN of the section of the inlet is calculated.

The measuring method comprises the following steps:

the first step: a system mounting bracket is made, which can be made using prior art techniques.

The low-head concrete volute hydropower station runner inlet is high from the dam face, the channel is narrow, the installation flow measurement system is very difficult, the movable measuring support is manufactured by fully utilizing the position of the water inlet access door slot, and the access door slot can be used only when the power station unit is overhauled, so that the measuring support can be fixed in the access door slot to monitor the inlet flow in real time when the unit is in normal operation. The measuring bracket consists of a cross beam, a gate slot guide wheel and a sensor bracket with the position adjustable up and down, as shown in figure 8.

And a second step of: measurement system connection

The measuring system is provided with 7 flow rate sensors (the quantity of which can be adjusted according to the width of the water inlet and the measuring precision) for measuring the flow rate of the inlet section, and 1 water level sensor is used for measuring the water depth of the measuring position of the flow rate of the inlet section. Each sensor is converted into a 4-20mA signal after passing through a pre-signal processor and is input into an acquisition module, an analysis and measurement controller acquires real-time data from the acquisition module, and the system connection is shown in figure 1.

And a third step of: section flow velocity measurement curve cluster acquisition and calibration

In order to realize accurate measurement of the flow of the inlet section, a flow velocity-water level characteristic curve of the longitudinal direction (7 longitudinal sections in the scheme) of the inlet section needs to be obtained, and the obtaining method comprises the following steps:

11 working condition points are respectively arranged on the unit belt, namely 0% Pe, 10% Pe, 20% Pe, 30% Pe, 40% Pe, 50% Pe, 60% Pe, 70% Pe, 80% Pe, 90% Pe and 100% Pe, the measuring bracket is moved up and down (the measuring moving interval can be reasonably selected according to the inlet height, the smaller the interval is, the better the fitting degree of the fitted flow velocity-water level curve is), the flow velocity under different water levels of the longitudinal sections is measured, and a flow velocity distribution curve is fitted at each working condition point, so that 7 flow velocity-water head curve clusters (11 curves) of the longitudinal sections are obtained. The measurement schematic is shown in fig. 9.

And a third step of: real-time flow calculation

The actual measurement data are recorded into a controller database, the calculation software fits 11 flow velocity-water head curve clusters of each section according to the data, and the flow velocity-water head distribution characteristic is submerged according to the hydraulic thick-wall orifice, and the flow velocity and the water level are in a quadratic parabolic relationship, namely the following equation characteristic is satisfied:

wherein V-flow velocity, rho-water density, g-gravity acceleration, mu-water viscosity coefficient, hf-head loss are constants, H0-inlet cross section central line elevation, H-relative central water level.

When the measuring system is put into operation, the flow rate measuring sensor is positioned at the transverse central axis of the orifice, the flow rate at the position of the central axis is measured, the flow rate is also the maximum flow rate Vrel, the program automatically selects two characteristic curves with the flow rate peak value closest to the Vrel value from 11 curves according to the maximum flow rate value, namely, the peak values V1max and V2max of the selected curves satisfy the relation: v1max is less than Vrel is less than V2max, the program fits the flow velocity-water head characteristic curves of 7 longitudinal sections under the current working condition according to the two-day curves, and the total inlet flow rate Q sigma can be obtained by integrating 7 flow velocity-water head characteristic curves and accumulating the flow velocity-water head characteristic curves.

In conclusion, the method can be convenient for measurement and calculation, and accurate measurement of the flow of the inlet section is realized.

It is important to note that the construction and arrangement of the application as shown in the various exemplary embodiments is illustrative only. Although only a few embodiments have been described in detail in this disclosure, those skilled in the art who review this disclosure will readily appreciate that many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters (e.g., temperature, pressure, etc.), mounting arrangements, use of materials, colors, orientations, etc.) without materially departing from the novel teachings and advantages of the subject matter described in this application. For example, elements shown as integrally formed may be constructed of multiple parts or elements, the position of elements may be reversed or otherwise varied, and the nature or number of discrete elements or positions may be altered or varied. Accordingly, all such modifications are intended to be included within the scope of present application. The order or sequence of any process or method steps may be varied or re-sequenced according to alternative embodiments. In the claims, any means-plus-function clause is intended to cover the structures described herein as performing the recited function and not only structural equivalents but also equivalent structures. Other substitutions, modifications, changes and omissions may be made in the design, operating conditions and arrangement of the exemplary embodiments without departing from the scope of the present applications. Therefore, the application is not limited to the specific embodiments, but extends to various modifications that nevertheless fall within the scope of the appended claims.

Furthermore, in order to provide a concise description of the exemplary embodiments, all features of an actual implementation may not be described (i.e., those not associated with the best mode presently contemplated for carrying out the application, or those not associated with practicing the application).

It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions may be made. Such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure.

It should be noted that the above embodiments are only for illustrating the technical solution of the present application and not for limiting the same, and although the present application has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the technical solution of the present application may be modified or substituted without departing from the spirit and scope of the technical solution of the present application, which is intended to be covered in the scope of the claims of the present application.

Claims (10)

1. The utility model provides a low water head power station mixes earth spiral case flow measurement system which characterized in that: comprising the steps of (a) a step of,

a remote system (1) comprising a circuit breaker module (10), an arithmetic controller (11) connected with the circuit breaker module (10), and a monitoring terminal (12) connected with the arithmetic controller (11);

the acquisition system (2) comprises a signal acquisition module (20) which is in wireless connection with the operation controller (11), a plurality of groups of flow rate sensors (21) which are connected with the signal acquisition module (20), and a water level sensor (22) which is connected with the signal acquisition module (20);

and the hoisting device (3) is arranged at the water inlet access door slot of the hydropower station and used for controlling the position change of the plurality of groups of sensors.

2. A low head power plant concrete volute flow measurement system as defined in claim 1, wherein: the remote system (1) further comprises a display module (13), a warning module (14) and an output module (15) which are connected with the monitoring terminal (12); the warning module (14) comprises a warning lamp (141); the output module (15) includes a printer (151).

3. A low head power plant concrete volute flow measurement system as claimed in claim 2, wherein: the acquisition system (2) further comprises a temperature sensor and a pressure sensor which are connected with the signal acquisition module (20); the temperature sensor, the pressure sensor and the liquid level sensor are respectively used for measuring temperature and pressure data and transmitting the temperature and pressure data to the operation controller (11) through the signal acquisition module (20) so as to assist a worker in judging the water flow condition.

4. A low head power plant concrete volute flow measurement system as claimed in claim 3, wherein: the device also comprises a signal conversion module (23) connected with the flow rate sensor (21); the acquisition system (2) is provided with the flow rate sensor (21) for measuring the flow rate of the inlet section; the water level sensor (22) is used for measuring the water depth of an inlet section flow velocity measuring position; each sensor is converted into a 4-20mA signal through a front signal conversion module (23) and then is input into a signal acquisition module (20), and the operation controller (11) acquires real-time data from the signal acquisition module (20).

5. The low head power station concrete volute flow measurement system of claim 4, wherein: the monitoring terminal (12) comprises a computer (121); the display module (13) comprises an external display screen (131); protection of the power supply lines and electrical equipment is carried out at the remote system (1) by means of a circuit breaker module (10), which automatically cuts off the circuit when serious overload or short-circuit and under-voltage faults occur.

6. The low head power station concrete volute flow measurement system of claim 5, wherein: the operation controller (11) receives real-time data and transmits the real-time data to the monitoring terminal (12), and the monitoring terminal (12) processes the data and displays the data in real time through the display module (13).

7. The low head power station concrete volute flow measurement system of claim 6, wherein: when the flow speed data and the water level data processed by the monitoring terminal (12) reach the range of the preset warning value, the monitoring terminal (12) gives an early warning through the warning module (14).

8. A low head power station concrete volute flow measurement system as defined in any one of claims 1 to 7, wherein: the circuit breaker module (10) comprises a mounting frame unit (100) and a circuit breaker; the mounting frame unit (100) comprises a hollow base component (101), a movable supporting plate component (102) movably inserted with the hollow base component (101), a lifting table component (103) arranged at one end of the hollow base component (101), and a positioning clamping component (104) which is in limiting connection with the lifting table component (103) and is partially arranged in the movable supporting plate component (102).

9. The low head power station concrete volute flow measurement system of claim 8, wherein: the hollow base assembly (101) comprises a hollow wire holder (101 a), a wire connection port (101 b) arranged above the hollow wire holder (101 a), a limit monorail (101 c) arranged at one end of the middle part of the hollow wire holder (101 a), a stop plate (101 d) arranged at one end of the hollow wire holder (101 a), and a spring (101 e) connected with the inner wall of the stop plate (101 d) and connected with the outer wall of the movable supporting plate assembly (102); the movable supporting plate assembly (102) comprises a top moving plate (102 a) arranged at one end of the movable supporting plate assembly, a panel (102 b) connected with one side of the top moving plate (102 a), and four groups of limiting supporting plates (102 c) arranged on one side of the panel (102 b) along the vertical direction in an array manner; a positioning support space (M) is formed between the two groups of limit support plates (102 c); the lifting table assembly (103) comprises limit double rails (103 a) symmetrically arranged, four groups of bearing plates (103 b) arranged on the outer sides of the limit double rails (103 a) along the vertical direction in an array mode, arc-shaped positioning grooves (103 c) arranged on the bearing plates (103 b), and through lifting openings (103 d) arranged on the inner sides of the bearing plates (103 b).

10. The low head power station concrete volute flow measurement system of claim 9, wherein: the positioning clamping assembly (104) comprises a threaded mounting plate (104 a) with two ends in limiting insertion connection with the limiting double-rail (103 a), a threaded rod (104 b) in threaded connection with the threaded mounting plate (104 a), a supporting rotating head (104 c) arranged at one end of the threaded rod (104 b), a stopping disc (104 d) fixedly connected with the other end of the threaded rod (104 b), a conical top (104 e) connected with the stopping disc (104 d) and with a large diameter from large to small, a connecting plate (104 f) arranged at one side of the threaded mounting plate (104 a), a positioning inserting plate (104 g) connected with the tail end of the connecting plate (104 f), a double-layer clamping piece (104 h) arranged at one end of the positioning inserting plate (104 g) in contact with the conical top (104 e) and in insertion connection with the positioning inserting plate (104 g), and an elastic fastener (104 i) arranged at one end of the positioning inserting plate (104 g) and in insertion connection with the positioning inserting plate (104 g).