A water supply system and control method for a pumped storage power station

Abstract

This invention provides a water supply system and control method for a pumped storage power station. The water supply system includes a main water supply pipe and a main drainage pipe. The main water supply pipe is sequentially equipped with a maintenance ball valve, a flow indicator, a flow regulating valve, a technical water supply pump module, a pressure sensor, and a temperature sensor. The technical water supply pump module sequentially includes a maintenance ball valve, a variable frequency pump P1, a check valve, a water filter, and another maintenance ball valve. The drainage pipe is also equipped with a maintenance ball valve. The main water supply pipe also includes a main shaft sealing water supply branch and upper and lower leak-proof ring sealing branches. Between the main water supply pipe and the drainage pipe, there are also an upper guide bearing cooler, a generator air cooler, a thrust / lower guide bearing external circulation cooler, and a water guide external circulation cooler. The variable frequency pump P1, the flow regulating valve, and the control module can adapt to different unit loads and different water temperatures in the lower reservoir, adjusting the opening of the flow regulating valves and the pump speed of each user branch, achieving energy-saving and intelligent control functions.

Description

Technical Field

[0001] This invention relates to the field of water conservancy and hydropower technology, specifically to a water supply system and control method for pumped storage power stations. Background Technology

[0002] Pumped storage power stations have become important energy storage facilities to cope with the new power grid structure. However, the operation and maintenance of many pumped storage power stations still suffer from problems such as low levels of informatization, digitalization and intelligence. In particular, the auxiliary systems of the generating units are often neglected, and there are a series of problems in their design, equipment selection and operation scheduling.

[0003] Pumped storage power station technical water supply systems typically employ a unit-type water supply method. Each unit includes one water pump / turbine, one generator / motor, and a corresponding main transformer; each unit has two sets of water supply equipment, serving as primary and backup for each other; each set of water supply equipment includes one water pump, one filter, and various related valves, with connecting valves between the two sets of equipment. The commonly used water source is the tailwater of the unit; in special circumstances, water can be drawn from the public water supply system. The main problems with this technical water supply system are as follows:

[0004] (1) The technical water supply system is the main user of energy consumption in the power station operation, accounting for approximately 23.86% of the total annual power consumption of the power station, second only to the heating, ventilation, and air conditioning system. Researching energy-saving and consumption-reducing measures for the auxiliary water system can effectively promote energy conservation and consumption reduction in pumped storage power stations;

[0005] (2) When designing the technical water supply system of the unit, in order to cover the range of water temperature changes in the tailwater flow channel throughout the year, the primary side inlet water temperature of the cooler is designed according to the highest value of the year. Under this condition, the cooling water volume is large, which indirectly leads to the high-efficiency equipment often being in an inefficient operating state on site.

[0006] (3) The technical water supply pump operates according to the design conditions, and the outlet flow rate is not adjustable. Although the generator air cooler, thrust bearing, and upper guide bearing oil temperatures are equipped with electric regulating valves, which are automatically adjusted by the user's hot air temperature or oil temperature, forming a separate system. However, in the case of high-temperature operation in summer, where the thrust bearing oil temperature reaches or even exceeds the safety threshold, and the generator air cooler hot air temperature has a large safety margin, the electric valves cannot automatically achieve a more reasonable flow distribution. Therefore, repeated manual testing is required, resulting in a long response cycle. Furthermore, considering the overall safety of the unit, the adjustment range should not be too large, and there is a lack of theoretical support.

[0007] Furthermore, with the innovation and application of new technologies such as artificial intelligence, cloud platforms, and big data in the intelligent construction of hydropower plants, the level of intelligence and digitalization of hydropower stations is becoming increasingly higher. However, there is a lack of intelligent and efficient monitoring, analysis, prediction, and early warning functions for auxiliary systems such as oil, gas, and water. This results in the inability to guarantee the hydraulic safety and normal and stable operation of the technical water supply system's pipeline network, further affecting the safe operation of the generating units, and leading to a series of engineering problems such as decreased pump utilization and low energy efficiency. Summary of the Invention

[0008] The first objective of this invention is to provide a water supply system for pumped storage power plants, addressing the aforementioned problems.

[0009] To achieve the above objectives, the present invention adopts the following technical solution:

[0010] A water supply system for a pumped storage power station includes a main water supply pipe and a main drainage pipe. The main water supply pipe is connected to a water intake, and the main drainage pipe is connected to a drain outlet. The main water supply pipe is sequentially equipped with a maintenance ball valve, a flow indicator, a flow regulating valve, a technical water supply pump module, a pressure sensor, and a temperature sensor. The technical water supply pump module sequentially includes a maintenance ball valve, a variable frequency pump P1, a check valve, a water filter, and a maintenance ball valve. The main drainage pipe is equipped with a maintenance ball valve.

[0011] The main water supply pipe is also equipped with a spindle sealing water supply branch and upper and lower leak-proof ring sealing branches. The spindle sealing water supply branch is equipped with a spindle sealing water supply pump module, a flow regulating valve, a flow indicator, a pressure sensor, and a maintenance ball valve in sequence. The spindle sealing water supply pump module is equipped with a maintenance ball valve, a water pump P2, a maintenance ball valve, a pressure indicator, a water filter, a check valve, and a maintenance ball valve in sequence.

[0012] The upper and lower leak-proof ring sealing branches are sequentially equipped with a maintenance ball valve, a water filter, a flow regulating valve, a pressure sensor, a flow indicator, a check valve, and a maintenance ball valve.

[0013] Between the main water supply pipe and the main drainage pipe, there is also an upper guide bearing cooler, a generator air cooler, a thrust / lower guide bearing external circulation cooler, and a water guide external circulation cooler.

[0014] While adopting the above technical solutions, the present invention may also adopt or combine the following technical solutions:

[0015] As a preferred technical solution of the present invention: the water supply branch pipes of the upper guide bearing cooler, the generator air cooler, the thrust / lower guide bearing external circulation cooler, and the water guide external circulation cooler are sequentially equipped with a flow regulating valve and a maintenance ball valve.

[0016] As a preferred technical solution of the present invention: the upper guide bearing cooler, the generator air cooler, the thrust / lower guide bearing external circulation cooler, the water guide external circulation cooler drain branch pipe flow indicator, and the maintenance ball valve.

[0017] As a preferred technical solution of the present invention: the cooler body and front and rear of the upper guide bearing cooler, generator air cooler, thrust / lower guide bearing external circulation cooler, and water external circulation cooler are provided with temperature sensors.

[0018] As a preferred embodiment of the present invention, pressure signal devices are provided before and after the generator air cooler.

[0019] As a preferred technical solution of the present invention: a water thermometer is provided in the lower reservoir of the tailrace emergency gate.

[0020] As a preferred embodiment of the present invention, the water supply system further includes a user temperature monitoring module, a variable frequency pump control module, a flow regulating valve control module, an alarm protection control module, and a logic control module.

[0021] The user temperature monitoring module is used to monitor the water temperature in the lower reservoir, the water temperature in the main technical water supply pipe, the water temperature before and after the coolers in each branch of the technical water supply, and the user tile temperature in each branch.

[0022] The variable frequency pump control module is used to control the start-up, shutdown, and speed change of the variable frequency water pump P1 in the technical water supply pump module of the system.

[0023] The flow control module can control the opening degree of the flow control valves in the main water supply pipe and each branch pipe.

[0024] The alarm protection control module is used to trigger an alarm based on the temperature alarm setting value of each branch user.

[0025] The logic control module is used to control the frequency converter pump control module and the flow regulating valve control module according to the preset logic control system and the input user temperature monitoring module.

[0026] The second objective of this invention is to provide a control method for a water supply system of a pumped storage power station.

[0027] Therefore, the above-mentioned objective of the present invention is achieved through the following technical solution:

[0028] A control method for a water supply system of a pumped storage power station, characterized in that: the control method is based on the water supply system described above and includes the following steps:

[0029] S1: The user temperature detection module obtains the heat output and water temperature of each user when the unit is running at different loads, and inputs them into the logic control module. When the temperature of a user in a certain branch exceeds the set value, it is input into the alarm protection control module.

[0030] S2: The logic control module calculates the water demand of different user branches and the total flow required by the main pipe. The alarm protection control module controls the flow regulating valve control module and the frequency converter pump control module to adjust the flow regulating valve to the preset maximum opening and the frequency converter pump to the preset maximum speed. If the water temperature of a user branch still exceeds the set value, the alarm protection is triggered and the machine is stopped for inspection.

[0031] S3: Input the calculation results of the logic control module into the flow regulating valve control module and the frequency converter pump control module;

[0032] S4: Set the opening degree of the flow control valve and the speed of the variable frequency pump by querying the load-lower reservoir water temperature-flow control valve opening table and the load-lower reservoir water temperature-variable frequency pump speed table respectively.

[0033] This invention provides a water supply system and control method for pumped storage power stations, which has the following advantages: the variable frequency pump P1, the flow regulating valve and the control module can adapt to different unit loads and different water temperatures in the lower reservoir, and adjust the opening degree of the flow regulating valve and the pump speed of each user branch, thus realizing the functions of energy saving and intelligent regulation. Attached Figure Description

[0034] Figure 1 This is a layout diagram of the water supply system for a pumped storage power station provided by the present invention.

[0035] Figure 2 This is a logic diagram of the control method provided by the present invention.

[0036] In the diagram: 1-Main water supply pipe; 2-Technical water supply pump module; 3-Drainage main pipe; 4-Main shaft seal water supply branch; 5-Upper and lower leak-proof ring seal branch; 6-Upper guide bearing cooler; 7-Generator air cooler; 8-Thrust / lower guide bearing external circulation cooler; 9-Water guide bearing external circulation cooler; 41-Main shaft seal water supply pump module. Detailed Implementation

[0037] The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.

[0038] like Figure 1-2 As shown, a water supply system for a pumped storage power station includes a main water supply pipe and a main drainage pipe. The main water supply pipe is connected to a water intake, and the main drainage pipe is connected to a drain outlet. The main water supply pipe is sequentially equipped with a maintenance ball valve, a flow indicator, a flow regulating valve, a technical water supply pump module, a pressure sensor, and a temperature sensor. The technical water supply pump module sequentially includes a maintenance ball valve, a variable frequency water pump P1, a check valve, a water filter, and a maintenance ball valve. The main drainage pipe is equipped with a maintenance ball valve.

[0039] The main water supply pipe is also equipped with a spindle sealing water supply branch and upper and lower leak-proof ring sealing branches. The spindle sealing water supply branch is equipped with a spindle sealing water supply pump module, a flow regulating valve, a flow indicator, a pressure sensor, and a maintenance ball valve in sequence. The spindle sealing water supply pump module is equipped with a maintenance ball valve, water pump P2, a maintenance ball valve, a pressure indicator, a water filter, a check valve, and a maintenance ball valve in sequence.

[0040] The upper and lower leak-proof ring sealing branches are equipped with a maintenance ball valve, a water filter, a flow regulating valve, a pressure sensor, a flow indicator, a check valve, and a maintenance ball valve in sequence.

[0041] Between the water supply main pipe and the drainage main pipe, there are also upper guide bearing coolers, generator air coolers, thrust / lower guide bearing external circulation coolers, and water guide external circulation coolers.

[0042] The water supply branch pipes of the upper guide bearing cooler, generator air cooler, thrust / lower guide bearing external circulation cooler, and water guide external circulation cooler are sequentially equipped with flow regulating valves and maintenance ball valves.

[0043] Upper guide bearing cooler, generator air cooler, thrust / lower guide bearing external circulation cooler, water guide external circulation cooler drain branch pipe flow indicator, maintenance ball valve.

[0044] Temperature sensors are installed on the body and front and rear of the upper guide bearing cooler, generator air cooler, thrust / lower guide bearing external circulation cooler, and water external circulation cooler.

[0045] Pressure signal devices are also installed before and after the generator air cooler.

[0046] A water thermometer is installed in the lower reservoir of the tailrace emergency gate.

[0047] The water supply system also includes a user temperature monitoring module, a variable frequency pump control module, a flow regulating valve control module, an alarm protection control module, and a logic control module;

[0048] The user temperature monitoring module is used to monitor the water temperature in the lower reservoir, the water temperature in the main technical water supply pipe, the water temperature before and after the coolers in each branch of the technical water supply, and the user tile temperature in each branch.

[0049] The variable frequency pump control module is used to control the start-up, stop, and speed changes of the variable frequency water pump P1 in the technical water supply pump module of the system.

[0050] The flow control module can control the opening degree of the flow control valves in the main water supply pipe and each branch pipe;

[0051] The alarm protection control module is used to trigger an alarm based on the temperature alarm settings of each branch user.

[0052] The logic control module is used to control the variable frequency pump control module and the flow regulating valve control module according to the preset logic control system and the user temperature monitoring module.

[0053] Specifically, the water supply system for the pumped storage power station is controlled in the following manner:

[0054] The known conditions are: the flow rate-opening curve of the flow regulating valve, that is, after selecting the flow regulating valve, the flow rate value corresponding to the flow regulating valve can be obtained by adjusting the different openings of the flow regulating valve; and the speed-flow rate curve of the variable frequency pump P1, that is, after selecting the variable frequency pump, the flow rate value corresponding to the pump can be obtained by adjusting the speed of the variable frequency pump.

[0055] S1: The user temperature detection module obtains the heat output and water temperature of each user when the unit is running at different loads, and inputs them into the logic control module. When the temperature of a user in a certain branch exceeds the set value, it is input into the alarm protection control module.

[0056] S2: The logic control module calculates the water demand of different user branches and the total flow required by the main pipe. The alarm protection control module controls the flow regulating valve control module and the frequency converter pump control module to adjust the flow regulating valve to the preset maximum opening and the frequency converter pump to the preset maximum speed. If the water temperature of a user branch still exceeds the set value, the alarm protection is triggered and the machine is stopped for inspection.

[0057] S3: Input the calculation results of the logic control module into the flow regulating valve control module and the frequency converter pump control module;

[0058] S4: Set the opening degree of the flow control valve and the speed of the variable frequency pump by querying the load-lower reservoir water temperature-flow control valve opening table and the load-lower reservoir water temperature-variable frequency pump speed table respectively.

[0059] The combined operating conditions of load, lower reservoir water temperature, and flow control valve opening are shown in Table 1, and the combined operating conditions of load, lower reservoir water temperature, and variable frequency pump speed are shown in Table 2.

[0060] Table 1

[0061]

[0062] Table 2

[0063]

[0064] The above specific embodiments are used to explain and illustrate the present invention, and are only preferred embodiments of the present invention, not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made to the present invention within the spirit and scope of the claims shall fall within the protection scope of the present invention.

Claims

1. A water supply system for a pumped-storage power station, comprising a main water supply pipe and a main drainage pipe, wherein the main water supply pipe is connected to a water intake, and the main drainage pipe is connected to a drainage outlet, characterized in that: The main water supply pipe is sequentially equipped with a maintenance ball valve, a flow indicator, a flow regulating valve, a technical water supply pump module, a pressure sensor, and a temperature sensor. The technical water supply pump module sequentially includes a maintenance ball valve, a variable frequency water pump P1, a check valve, a water filter, and a maintenance ball valve. The main drain pipe is equipped with a maintenance ball valve. The main water supply pipe is also equipped with a spindle sealing water supply branch and upper and lower leak-proof ring sealing branches. The spindle sealing water supply branch is equipped with a spindle sealing water supply pump module, a flow regulating valve, a flow indicator, a pressure sensor, and a maintenance ball valve in sequence. The spindle sealing water supply pump module is equipped with a maintenance ball valve, a water pump P2, a maintenance ball valve, a pressure indicator, a water filter, a check valve, and a maintenance ball valve in sequence. The upper and lower leak-proof ring sealing branches are sequentially equipped with a maintenance ball valve, a water filter, a flow regulating valve, a pressure sensor, a flow indicator, a check valve, and a maintenance ball valve. Between the main water supply pipe and the main drainage pipe, there is also an upper guide bearing cooler, a generator air cooler, a thrust / lower guide bearing external circulation cooler, and a water guide external circulation cooler.

2. The water supply system for a pumped storage power station according to claim 1, characterized in that: The water supply branch pipes of the upper guide bearing cooler, generator air cooler, thrust / lower guide bearing external circulation cooler, and water guide external circulation cooler are sequentially equipped with a flow regulating valve and a maintenance ball valve.

3. The water supply system for a pumped storage power station according to claim 1, characterized in that: The upper guide bearing cooler, generator air cooler, thrust / lower guide bearing external circulation cooler, water guide external circulation cooler drain branch pipe flow indicator, and maintenance ball valve are all mentioned.

4. The water supply system for a pumped storage power station according to claim 1, characterized in that: Temperature sensors are provided on the cooler body and front and rear of the upper guide bearing cooler, generator air cooler, thrust / lower guide bearing external circulation cooler, and water external circulation cooler.

5. The water supply system for a pumped storage power station according to claim 1, characterized in that: Pressure signal devices are also installed before and after the generator air cooler.

6. The water supply system for a pumped storage power station according to claim 1, characterized in that: A water thermometer is installed in the lower reservoir of the tailrace emergency gate.

7. The water supply system for a pumped storage power station according to claim 1, characterized in that: The water supply system also includes a user temperature monitoring module, a variable frequency pump control module, a flow regulating valve control module, an alarm protection control module, and a logic control module; The user temperature monitoring module is used to monitor the water temperature in the lower reservoir, the water temperature in the main technical water supply pipe, the water temperature before and after the coolers in each branch of the technical water supply, and the user tile temperature in each branch. The variable frequency pump control module is used to control the start-up, shutdown, and speed change of the variable frequency water pump P1 in the technical water supply pump module of the system. The flow control module can control the opening degree of the flow control valves in the main water supply pipe and each branch pipe. The alarm protection control module is used to trigger an alarm based on the temperature alarm setting value of each branch user. The logic control module is used to control the frequency converter pump control module and the flow regulating valve control module according to the preset logic control system and the input user temperature monitoring module.

8. A control method for a water supply system of a pumped storage power station, characterized in that: The control method is based on the water supply system for pumped storage power stations as described in any one of claims 1-7, and includes the following steps: S1: The user temperature detection module obtains the heat output and water temperature of each user when the unit is running at different loads, and inputs them into the logic control module. When the temperature of a user in a certain branch exceeds the set value, it is input into the alarm protection control module. S2: The logic control module calculates the water demand of different user branches and the total flow required by the main pipe. The alarm protection control module controls the flow regulating valve control module and the frequency converter pump control module to adjust the flow regulating valve to the preset maximum opening and the frequency converter pump to the preset maximum speed. If the water temperature of a user branch still exceeds the set value, the alarm protection is triggered and the machine is stopped for inspection. S3: Input the calculation results of the logic control module into the flow regulating valve control module and the frequency converter pump control module; S4: Set the opening degree of the flow control valve and the speed of the variable frequency pump by querying the load-lower reservoir water temperature-flow control valve opening table and the load-lower reservoir water temperature-variable frequency pump speed table respectively.

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