Pump storage model test device capable of measuring sediment concentration and test method thereof

Abstract

The present application belongs to the technical field of pumped storage power station model test, and specifically discloses a pumped storage model test device capable of measuring sediment concentration through the machine and a test method thereof, which comprises a model upper reservoir, a model lower reservoir and a forebay, and a pumped model and a discharged model are arranged between the model upper reservoir and the model lower reservoir; the pumped model and the discharged model are both composed of a flow intelligent control module, a sediment monitoring module through the machine and a water delivery pipeline. The present application uses the pumped storage model test device capable of measuring sediment concentration through the machine and the test method thereof, and from the perspective of model test, the sediment concentration through the machine is measured in real time for the operation condition of the pumped storage power station, the response change thereof to different water and sediment conditions is investigated, scientific basis is provided for the safe operation of the water pump and the optimization of the sediment control strategy, and thus the problem of insufficient monitoring and understanding of the sediment concentration through the machine in the actual operation process of the pumped storage power station in the prior art is solved.

Description

Technical Field

[0001] This invention belongs to the technical field of pumped storage power station model testing, specifically relating to a pumped storage model testing device and its testing method that can measure the sediment content of pumped water. Background Technology

[0002] In recent years, the installed capacity of clean energy sources such as wind and solar power in my country has continued to climb, but their output is greatly affected by natural conditions. Pumped storage power stations, as key facilities for peak shaving and valley filling in the power system and balancing the volatility of new energy sources, play an important role in building a new power system.

[0003] Of the nine newly planned clean energy bases in my country, more than half are located in sediment-laden river basins such as the middle and upper reaches of the Yellow River and the Jinsha River. However, the water flow in these areas carries a large amount of sediment. During pumped-storage power generation, the water flow and sediment act together on the turbine blades and flow channels, leading to severe erosion damage, reduced efficiency, and shortened equipment lifespan. Therefore, precise control and monitoring of sediment content passing through the turbines has become a core challenge in the design, operation, and optimization of pumped-storage power stations on sediment-laden rivers.

[0004] Currently, the method for determining the sediment load through pumped-storage power stations can be calculated using mathematical models (see Chinese Invention Patent CN201610705864.2 and Chinese Invention Patent CN202310872576.6 for relevant patents). However, the verification of mathematical models requires substantial support from actual data, and the current amount of measured sediment load through pumped-storage stations is insufficient, making it difficult to guarantee the reliability of the models. Existing pumped-storage model experiments mainly focus on the hydraulic characteristics of the inlet and outlet of pumped-storage power stations (see Chinese Invention Patent CN202311232379.4 for relevant patents), but there is a lack of clear understanding of the real-time changes in sediment load through pumped-storage power stations during actual operation and its relationship with the sediment load at the intake.

[0005] Therefore, there is a need in this field to develop a pumped storage model test device and its test method that can measure the sediment content of pumped water, so as to effectively solve the above problems. Summary of the Invention

[0006] The purpose of this invention is to provide a pumped storage model test device and its test method that can measure the sediment content passing through the pump. From the perspective of model testing, the device measures the sediment content passing through the pump in real time under the operating conditions of the pumped storage power station, and examines its response to different water and sediment conditions. This provides a scientific basis for the safe operation of the pump and the optimization of sediment control strategies, thereby solving the problem of insufficient monitoring and understanding of sediment content passing through the pump in the actual operation of the pumped storage power station in the existing technology.

[0007] To achieve the above objectives, the present invention provides a pumped storage model test device capable of measuring sediment content passing through the pump, comprising an upper model reservoir, a lower model reservoir, and a forebay. A pumping model and a discharge model are provided between the upper and lower model reservoirs. Both the pumping and discharge models consist of a flow intelligent control module and a sediment monitoring module. Sediment monitoring modules are provided at both ends of the flow intelligent control module. The flow intelligent control module and the sediment monitoring module, as well as the upper and lower model reservoirs and the sediment monitoring module, are connected by water pipelines.

[0008] Preferably, both the upper and lower reservoirs of the model are adapted to the shape of the prototype reservoir and have been scaled down; both the upper and lower reservoirs of the model are made of LLDPE material.

[0009] Preferably, the forebay is equipped with a sand inlet and a mixing pump. The forebay and the model's lower reservoir are connected sequentially by a first water pump and a PVC wire hose. A certain amount of clean water is placed in the forebay. According to the test requirements, the corresponding mass of silt is added through the sand inlet. The mixing pump is turned on to mix the water and silt evenly to reach the set silt content. Then, the silt is fed into the model's lower reservoir through the PVC wire hose.

[0010] The forebay is connected to the model reservoir to mix clear water and sediment, ensuring that the sediment content entering the model reservoir remains constant during the experiment.

[0011] Preferably, the intelligent flow control module consists of an intelligent DN32 anti-corrosion lined electromagnetic flow meter, a PLC controller, a frequency converter, and a second water pump;

[0012] Electromagnetic flow meters are used to indicate the flow rate of water in a pipeline in real time and convert the flow rate value into a standard process signal, which is then transmitted to the analog input module of the PLC via a signal cable.

[0013] The PLC controller presets a target flow rate value. It receives the real-time flow rate signal from the flow meter, compares it with the preset target flow rate setpoint, and performs calculations based on the preset PID (proportional-integral-derivative) control algorithm to generate and output the corresponding control signal.

[0014] The second water pump directly alters the water flow rate within the water delivery pipeline by changing its rotational speed, thus achieving dynamic control of the water flow rate. Each of the two water delivery pipelines is equipped with a water pump to simulate the pumping operation of a pumped-storage power station, enabling the pumping of sediment-laden water with a certain sediment content between the lower and upper reservoirs of the model.

[0015] The sediment monitoring module includes a Model 3150 infrared sediment analyzer, a sediment concentration monitoring sensor, a sediment sampling port, and a recording terminal. The sediment concentration monitoring sensor is located on the inner wall of the water delivery pipes at both ends (upstream and downstream) of the intelligent flow control module. Its data can be recorded on the terminal for real-time monitoring of sediment concentration in the flow. The sediment sampling port is located on the outside of the water delivery pipe of the sediment concentration monitoring sensor. The Model 3150 infrared sediment analyzer is used to measure the sediment concentration of water samples taken from upstream and downstream of the pump through the sediment sampling port, and is used for calibration and verification with the data from the sediment concentration monitoring sensor.

[0016] The intelligent flow control module is connected to the water supply pipeline via a socket joint, with adhesive filling the gap between them.

[0017] Preferably, PVC steel wire hoses are installed between the upper reservoir and the lower reservoir of the model and the water conveyance pipeline; the water conveyance pipeline includes UPVC straight pipes and UPVC 90-degree large arc bends, all of which are transparent and visible, and the internal structure can be clearly observed with the naked eye under normal lighting conditions, thus facilitating the observation of the water and sediment movement state during the experiment.

[0018] Preferably, the water supply pipeline, the intelligent flow control module, and the sediment monitoring module are all fixed on the load-bearing bracket. Ring clamps are installed every 30cm to secure the pipeline. The load-bearing bracket uses 5cm×10cm cross-section profiles. The bottom of the load-bearing bracket is equipped with several M16 adjustable support feet (D80×M16×L100), with an adjustable height of 10cm to adapt to different foundation conditions.

[0019] This invention also provides a test method for a pumped storage model test device capable of measuring sediment content during pumping, comprising the following steps:

[0020] Step S1: According to the model test conditions, drain water from the reservoir on the model to the dead water level;

[0021] Step S2: Based on the model test conditions, determine the sediment content and total water extraction volume of the reservoir under the model. Add water and sand to the forebay and stir until the sediment content of the test conditions is reached. After entering the reservoir under the model, start the test.

[0022] Step S3: Based on the model test conditions, the pumping flow rate, pumping time, stilling time, discharge flow rate, discharge time, and number of cycles are controlled and set through the flow intelligent control module to simulate the entire process of pumping, stilling, and discharging of the pumped storage power station.

[0023] Step S4: Take water samples 5 times at the sediment sampling ports of the pumping and discharging models at equal intervals of one-fifth of the pumping and discharging times, and mark the sampling times.

[0024] Step S5: After each water sample is stirred evenly, its sand content is measured using an infrared sand analyzer, and then compared, calibrated, and verified with the data from the sand content monitoring sensor.

[0025] Step S6: Establish a graph showing the change in sediment content at different times, and conduct a series of tests and quantitative studies on the influencing factors of sediment content in the passing sediment under the model test conditions.

[0026] The present invention employs the above-mentioned pumped storage model test device and test method capable of measuring sediment content during pumping, and has the following beneficial effects:

[0027] (1) It can perform relatively accurate real-time dynamic monitoring of sediment passing through the pump: The pumped storage model test device in this invention, through the coordinated deployment of sediment content monitoring sensor and sampling calibration, not only realizes the real-time measurement and synchronous data acquisition of sediment passing through the pump, but also ensures the consistency and reliability of the data, providing real-time data support for the analysis of sediment response under dynamic working conditions.

[0028] (2) It can simulate the entire working condition of a pumped storage power station: The pumped storage model test device in this invention can detect the flow signal in real time and adjust the flow rate precisely through the flow intelligent control module, set the cycle period, simulate the entire process of pumping, stilling and releasing water, and truly reflect the dynamic interaction of water and sediment in the actual operation of the power station.

[0029] (3) Significant engineering application value: The pumped storage model test device in this invention can guide the optimization of turbine selection, the formulation of sediment control strategy and the selection of pumping time by analyzing the influencing factors and quantitative relationship of sediment content in the turbine, and provide a scientific basis for the safe operation of pumped storage power stations in sandy river basins.

[0030] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the overall structure of the pumped storage energy model test device and its test method embodiment that can measure the sediment content of the pumped water.

[0032] Figure 2 This is a schematic diagram of the structure of the forebay and the lower reservoir of the pumped storage model test device and test method for measuring sediment content during pumping, as described in the present invention.

[0033] Figure 3 This is a schematic diagram of the intelligent flow control module in an embodiment of the pumped storage model test device and test method for measuring sediment content in pumped water.

[0034] Figure 4This is a schematic diagram of the sediment monitoring module in the pumped storage model test device and test method embodiment of the present invention, which can measure sediment content during pumping.

[0035] Figure Labels

[0036] 1. Upper reservoir of the model; 2. Lower reservoir of the model; 3. Forebay; 4. Water conveyance pipeline; 5. Load-bearing support; 6. Electromagnetic flow meter; 7. First water pump; 8. Frequency converter; 9. Sediment content monitoring sensor; 10. Sediment sampling port through the machine; 11. PVC steel wire hose; 12. Support pads; 13. Mixing pump; 14. Infrared sand meter; 15. PLC controller; 16. Second water pump. Detailed Implementation

[0037] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0038] Unless otherwise defined, the technical or scientific terms used in this invention shall have the ordinary meaning as understood by one of ordinary skill in the art to which this invention pertains.

[0039] like Figure 1 As shown, the pumped storage model test device capable of measuring sediment content during pumping includes an upper reservoir 1, a lower reservoir 2, and a forebay 3. A pumping model and a discharge model are installed between the upper reservoir 1 and the lower reservoir 2. Both the pumping and discharge models consist of a flow intelligent control module and a sediment monitoring module. Sediment monitoring modules are installed at both ends of the flow intelligent control module. The flow intelligent control module and the sediment monitoring module, as well as the upper reservoir 1 and the lower reservoir 2 and the sediment monitoring module, are connected via water pipelines 4.

[0040] Both the upper reservoir 1 and the lower reservoir 2 in the model are adapted to the shape of the prototype reservoir and have been scaled down. Both the upper reservoir 1 and the lower reservoir 2 in the model are made of LLDPE material.

[0041] like Figure 2 As shown, the forepool 3 is equipped with a sand inlet and a stirring pump 13. The forepool 3 and the model reservoir 2 are connected in sequence by a first water pump 7 and a PVC steel wire hose 11.

[0042] like Figure 3 As shown, the intelligent flow control module consists of an electromagnetic flowmeter 6, a PLC controller 15, a frequency converter 8, and a second water pump 16. Figure 4 As shown, the sediment monitoring module includes an infrared sand meter 14, a sediment content monitoring sensor 9, and a sediment sampling port 10. The sediment content monitoring sensor 9 is located on the inner wall of the water supply pipe 4 at both ends of the flow intelligent control module, and the sediment sampling port 10 is located on the outside of the water supply pipe 4 of the sediment content monitoring sensor 9.

[0043] The intelligent flow control module is connected to the water supply pipe 4 via a socket joint, with adhesive filling the gap between them. A PVC steel wire hose 11 is installed between the upper reservoir 1, the lower reservoir 2, and the water supply pipe 4. The water supply pipe 4 includes a UPVC straight pipe and a UPVC 90-degree large arc bend, both of which are transparent and visible. The water supply pipe 4, the intelligent flow control module, and the sediment monitoring module are all fixed to the load-bearing bracket 5. Several adjustable support feet 12 are located at the bottom of the load-bearing bracket 5, with an adjustable height of 10cm for each foot.

[0044] In this embodiment, a sand content of 1.66 kg / m³ was selected. 3 The sediment particle size was 0.09 mm, the inlet and outlet distance was 6.9 cm, the pumping time was 19.2 min, and the pumping flow rate was 4.32 m³ / h. 3 / h, still water time 12min, discharge time 19.2min, discharge flow rate 5.76m³ / h 3 / h, shearing height of 36.37cm, etc. are the working conditions of the model test.

[0045] A pumped storage model test device and its test method capable of measuring sediment content during pumping, comprising the following steps:

[0046] Step S1: Making the experimental model and initial debugging:

[0047] A. Based on the actual dimensions of the pumped storage power station in the sediment-bearing watershed, a test model was constructed using similarity criteria. This model included an upper reservoir (1), a lower reservoir (2), a forebay (3), a first pump (7), and a water conveyance pipeline (4). Representative water and sediment conditions were determined based on the actual pumping operation of the pumped storage power station and converted to the scale of the model test.

[0048] B. Based on the model test conditions, the correlation between the sediment concentration and the above variables was explored by adjusting the independent variable. In this embodiment, a sediment concentration of 1.66 kg / m³ was selected. 3 Comparing sand content 0.83 kg / m 3 The effect of sediment concentration passing through the pump was investigated. The effect of a sediment particle size of 0.09 mm on the sediment concentration passing through the pump was compared to that of a sediment particle size of 0.21 mm. The effect of a pumping time of 19.2 min on the sediment concentration passing through the pump was also compared to that of a pumping time of 9.6 min.

[0049] C. Based on the model test conditions, determine the models of the electromagnetic flowmeter 6, PLC controller 15, frequency converter 8, second water pump 16, sand content monitoring sensor 9, infrared sand meter 14, etc. in the flow intelligent control module and the sediment monitoring module.

[0050] D. Program and debug the PLC controller 15 in the intelligent flow control module to convert the flow value of the electromagnetic flowmeter 6 into a standard process signal, which is then transmitted to the analog input module of the PLC controller 15 via a signal cable. The PLC controller 15 receives the real-time flow signal from the electromagnetic flowmeter 6, compares it with the preset target flow value according to the program, and performs calculations based on the preset PID (proportional-integral-derivative) control algorithm to generate a corresponding control signal. This signal is then output to the frequency converter 8, which adjusts its output frequency to drive the motor speed of the second water pump 16 to change accordingly, thereby achieving dynamic control of the water flow rate.

[0051] E. Use 4 water pipes and 11 PVC steel wire hoses to connect the various parts.

[0052] Step S2: According to the model test conditions, release water into reservoir 1 on the model until the dead water level is reached.

[0053] Step S3: Based on the model test conditions, determine the sediment content and total pumping volume of the lower reservoir 2. Add water and sand to the forebay 3 and stir until the sediment content is within the test conditions. Then, enter the lower reservoir 2 to conduct the pumping cycle test of the pumped storage power station.

[0054] Step S4: Based on the model test conditions, the pumping flow rate, pumping time, stilling time, discharge flow rate, discharge time, and number of cycles are controlled and set through the flow intelligent control module to simulate the entire process of pumping, stilling, and discharging of the pumped storage power station.

[0055] In the pumping operation, the second water pump 16 is started to transport the sediment-laden water from the lower reservoir 2 of the model to the upper reservoir 1 of the model via the water conveyance pipeline 4. During this process, the pumping flow rate is dynamically adjusted by the frequency converter 8, the pipeline flow rate is monitored in real time by the electromagnetic flowmeter 6, and the sediment content monitoring sensor 9 monitors the sediment content passing through the pump upstream and downstream in real time. In the discharging operation, the second water pump 16 is started to transport the sediment-laden water from the upper reservoir 1 of the model to the lower reservoir 2 of the model via the water conveyance pipeline 4, and all the steps of the pumping operation are repeated. Based on the set model test conditions, a cyclic "pumping-discharging" test is carried out.

[0056] Step S5: At equal intervals of one-fifth of the pumping and discharging time, take water samples 5 times at the sediment sampling port 10 of the pumping and discharging models, and mark the sampling time.

[0057] Step S6: After each water sample is stirred evenly, its sand content is measured using a Model 3150 infrared sand analyzer 14, and compared, calibrated and verified with the data from the sand content monitoring sensor 9.

[0058] Step S7: Establish a graph showing the change in sediment content at different times, and conduct a series of tests and quantitative studies on the influencing factors of sediment content in the passing sediment under the model test conditions.

[0059] Correlation analysis was conducted on the experimental data to generate two-dimensional curves (e.g., to analyze the relationship between sediment concentration and sediment concentration passing through the machine), and three-dimensional cloud maps were generated (e.g., to analyze the relationship between pumping flow rate, pumping time, and sediment concentration passing through the machine). An empirical regression model was then established.

[0060] Therefore, this invention employs the aforementioned pumped storage model test device and its test method capable of measuring sediment content passing through pumps. From the perspective of model testing, it measures the sediment content passing through pumps in real time under the operating conditions of pumped storage power stations, examines its response to different water and sediment conditions, provides a scientific basis for the safe operation of pumps and the optimization of sediment control strategies, and thus solves the problem of insufficient monitoring and understanding of sediment content passing through pumps during the actual operation of pumped storage power stations in existing technologies.

[0061] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A pumped storage model test device capable of measuring sediment concentration, characterized by, The pump model and the water release model are arranged between the model upper reservoir and the model lower reservoir; the pump model and the water release model each comprise a flow intelligent control module and a machine-passing sediment monitoring module; the flow intelligent control module is provided with the machine-passing sediment monitoring module at both ends; the flow intelligent control module and the machine-passing sediment monitoring module and the model upper reservoir and the model lower reservoir and the machine-passing sediment monitoring module are connected through water conveying pipes; The flow intelligent control module comprises an electromagnetic flowmeter, a PLC controller, a frequency converter and a second water pump; the machine-passing sediment monitoring module comprises an infrared sediment measuring instrument, a sediment concentration monitoring sensor and a machine-passing sediment sampling port; the sediment concentration monitoring sensor is arranged on the inner wall of the water conveying pipe at both ends of the flow intelligent control module; and the machine-passing sediment sampling port is arranged on the outer side of the sediment concentration monitoring sensor. The flow intelligent control module and the water conveying pipe are connected through a socket joint, and the gap therebetween is filled with an adhesive. The test method of the pumped storage model test device comprises the following steps: Step S1, according to the model test working condition, the water is released to the dead water level in the model upper reservoir; Step S2, according to the model test working condition, the sediment concentration and the total water volume of the model lower reservoir are determined, the water and sand in the forebay are stirred to the sediment concentration of the test working condition, and the test is started after entering the model lower reservoir; Step S3, according to the model test working condition, the flow intelligent control module is used to control the pumping flow, pumping time, still water time, water release flow, water release time and the number of cycle periods, so as to simulate the whole process of pumping, still water and water release of the pumped storage power station; Step S4, according to the fifth of the pumping time and the water release time, water samples are taken at the machine-passing sediment sampling ports of the pump model and the water release model for 5 times at equal intervals, and the sampling time is marked; Step S5, each water sample is stirred uniformly and then the sediment concentration thereof is measured by using the infrared sediment measuring instrument, and the data is compared with the data of the sediment concentration monitoring sensor for calibration and verification; Step S6, a variation diagram of the sediment concentration at different times is established, and a series of tests on the influencing factors of the machine-passing sediment sediment concentration are carried out and quantitative research is conducted according to the model test working condition.

2. The model test device for measuring the pumped sediment concentration according to claim 1, wherein: The model upper reservoir and the model lower reservoir are adapted to the shape of the prototype reservoir and are processed by scaling; the model upper reservoir and the model lower reservoir are made of LLDPE material.

3. The model test device for measuring sediment concentration of pumped storage according to claim 1, wherein: The sand inlet and the stirring pump are arranged in the forebay, and the forebay is connected with the model lower reservoir through the first water pump and the PVC steel wire hose in sequence.

4. The model test apparatus for measuring sediment-laden pumping of a pumped storage power plant according to claim 1, wherein: PVC steel wire hoses are arranged between the model upper reservoir, the model lower reservoir and the water conveying pipes; the water conveying pipes comprise UPVC straight pipes and UPVC 90-degree circular arc elbow pipes.

5. The model test device for measuring the sediment concentration of pumped storage according to claim 4, characterized in that: The water conveying pipes, the flow intelligent control modules and the machine-passing sediment monitoring modules are fixed on the load-bearing supports, and a plurality of support foot pads are arranged at the bottom of the load-bearing supports, and the adjustment height of the support foot pads is 10 cm.

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