Water supply system and power generation facility
By directly driving the main feedwater pump with the main steam turbine and using a hydraulic coupling to regulate the water supply, the problem of low energy utilization rate of feedwater pumps in thermal power generating units is solved, achieving high-efficiency energy utilization and reducing energy conversion losses, and simplifying the system structure.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- CHINA CITY ENVIRONMENT PROTECTION ENGINEERING LIMITED COMPANY
- Filing Date
- 2025-06-16
- Publication Date
- 2026-04-21
AI Technical Summary
The existing thermal power generating unit feedwater pumps have low energy utilization rates, electric feedwater pumps require multiple energy conversions resulting in significant losses, and steam-driven feedwater pump systems are complex and require high equipment investment, resulting in low overall energy efficiency.
The main feedwater pump is directly driven by the main steam turbine, and the water supply is regulated by a hydraulic coupling to reduce energy conversion links. The main feedwater pump is driven by a high-efficiency main steam turbine, eliminating the need for a small steam turbine. The water supply is controlled by a standby electric feedwater pump and a flow meter.
It improves steam utilization, reduces energy conversion losses, reduces equipment investment and system complexity, and enhances overall energy efficiency.
Smart Images
Figure CN224149655U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of feed water for thermal power generating units, and particularly relates to a feed water system and a power generation facility. Background Technique
[0002] The energy conservation and consumption reduction of thermal power generating units have always mainly developed along the direction of high parameters and high efficiency. The main steam parameters of the units have continuously developed towards higher parameters and higher efficiency subcritical, supercritical, and ultra-supercritical parameters, greatly improving the energy utilization efficiency of the units. While the thermal power generating units are developing towards high parameters and high efficiency, the boiler feed water pressure of the thermal power generating units has also increased significantly, resulting in a significant increase in the head and power consumption of the feed pumps supporting the high-parameter and high-efficiency thermal power generating units, and a significant increase in the power required for driving the feed pumps.
[0003] The feed pump is a key auxiliary equipment of thermal power generating units. According to different driving methods, the existing feed pumps mainly adopt two driving methods: electric feed pumps and steam-driven feed pumps. Among them, the electric feed pump is driven by an electric motor, and the steam-driven feed pump is driven by a small steam turbine. For the electric feed pump, the power of the motor supporting the feed pump has increased significantly, resulting in a relatively large increase in the plant power consumption rate of the unit, and the capacity and equipment investment of the speed control devices such as the frequency converter supporting the electric feed pump have also increased significantly; at the same time, the energy required for driving the electric feed pump needs to be first converted from mechanical energy to electrical energy by the main steam turbine generator set, and then converted from electrical energy to mechanical energy for driving the feed pump by the feed pump motor. The number of conversions between electrical energy and mechanical energy is relatively large, and the energy conversion loss is relatively large. The steam-driven feed pump needs to add a small steam turbine with a relatively high equipment investment cost outside the steam turbine of the thermal power generating unit, and steam needs to be extracted from the high-parameter and high-efficiency main steam turbine to drive the small steam turbine, and the system is relatively complex; at the same time, compared with the efficiency of the high-efficiency main steam turbine, the efficiency of the small steam turbine for driving the feed pump is relatively low, and there is steam heat energy loss in the steam extraction of the main steam turbine to drive the small steam turbine of the feed pump, weakening the overall energy efficiency of the unit. There is a problem of relatively low energy utilization rate. Content of the Utility Model
[0004] The main purpose of the utility model is to propose a feed water system and a power generation facility, aiming to improve the problem of relatively low energy utilization rate.
[0005] To achieve the above object, the feed water system proposed by the utility model includes:
[0006] A main steam turbine, the steam inlet of the main steam turbine is used to connect to the outlet of the superheater, and the steam outlet of the main steam turbine is used to connect to the condenser;
[0007] A main feed pump, the water inlet of the main feed pump is used to connect to the deaerated feed water, and the water outlet of the main feed pump is used to connect to the main boiler feed water; and,
[0008] The hydraulic coupling has a pump wheel shaft and a turbine shaft, wherein the main shaft of the main steam turbine is driven to be connected to the pump wheel shaft, and the turbine shaft is driven to be connected to the pump shaft of the main feedwater pump.
[0009] In one embodiment, the water supply system further includes a generator set located between the main steam turbine and the hydraulic coupler. The main shaft of the main steam turbine is driven to be connected to the main shaft of the generator set, and the main shaft of the generator set is driven to be connected to the pump wheel shaft of the hydraulic coupler.
[0010] In one embodiment, both the pump wheel shaft and the turbine shaft are equipped with clutches.
[0011] In one embodiment, the clutch includes a multi-plate electromagnetic clutch.
[0012] In one embodiment, the hydraulic coupler includes an electro-hydraulic coupler.
[0013] In one embodiment, a flow meter is installed at the outlet of the main water supply pump.
[0014] In one embodiment, the water supply system further includes a controller, and both the electric hydraulic coupler and the flow meter are electrically connected to the controller.
[0015] In one embodiment, the water supply system further includes a generator set and a standby electric feedwater pump, wherein the main shaft of the main steam turbine is drivenly connected to the main shaft of the generator set, and the standby electric feedwater pump is electrically connected to the generator set.
[0016] In one embodiment, the rated flow rate of the standby electric water supply pump is not less than 30% of the rated flow rate of the main water supply pump; and / or,
[0017] The rated flow rate of the standby electric water supply pump shall not exceed 50% of the rated flow rate of the main water supply pump.
[0018] This utility model also proposes a power generation facility, including the aforementioned water supply system.
[0019] The water supply system includes:
[0020] The main steam turbine has an inlet for connecting to the superheater outlet and an outlet for connecting to the condenser.
[0021] A main feedwater pump, wherein the inlet of the main feedwater pump is connected to the deaerator feedwater, and the outlet of the main feedwater pump is connected to the boiler main feedwater; and,
[0022] The hydraulic coupling has a pump wheel shaft and a turbine shaft, wherein the main shaft of the main steam turbine is driven to be connected to the pump wheel shaft, and the turbine shaft is driven to be connected to the pump shaft of the main feedwater pump.
[0023] In this invention, the main steam turbine directly powers the main feedwater pump, reducing intermediate energy conversion. The elimination of a small steam turbine improves steam utilization and overall energy efficiency. Furthermore, by controlling the hydraulic coupler, the torque transmitted by the coupler can be controlled by adjusting its level or oil volume without altering the main steam turbine's rotational speed, thereby regulating the feedwater pump's real-time water supply. This overall improvement in steam and energy utilization enhances efficiency. Attached Figure Description
[0024] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.
[0025] Figure 1 A schematic diagram of the structure of an embodiment of the water supply system provided by this utility model;
[0026] Figure 2 This is a schematic diagram of another embodiment of the water supply system provided by this utility model.
[0027] Explanation of icon numbers:
[0028] 1. Main steam turbine; 2. Main feedwater pump; 3. Hydraulic coupling; 4. Generator set; 5. Clutch; 6. Flow meter; 7. Controller; 8. Standby electric feedwater pump; 9. Electric valve.
[0029] The realization of the purpose, functional features and advantages of this utility model will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation
[0030] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present utility model.
[0031] It should be noted that if there are directional indications (such as up, down, left, right, front, back...) involved in the embodiments of the present utility model, the directional indications are only used to explain the relative positional relationship and movement conditions between components in a specific posture. If the specific posture changes, the directional indications will also change accordingly.
[0032] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present utility model, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In addition, if "and / or" or "and / or" appears throughout the text, its meaning includes three parallel scenarios. Taking "A and / or B" as an example, it includes Scenario A, or Scenario B, or the scenario where both A and B are satisfied simultaneously. In addition, the technical solutions between various embodiments can be combined with each other, but it must be based on the ability of those of ordinary skill in the art to implement. When the combination of technical solutions results in contradictions or is unachievable, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present utility model.
[0033] The energy conservation and consumption reduction of thermal power generating units have mainly been along the development direction of high parameters and high efficiency. The main steam parameters of the units have continuously developed towards higher parameters and higher efficiency subcritical, supercritical, and ultra-supercritical parameters, significantly improving the energy utilization efficiency of the units. While the thermal power generating units are developing towards high parameters and high efficiency, the boiler feed water pressure of the thermal power generating units has also increased significantly, resulting in a significant increase in the head and power consumption of the feed pumps supporting the high-parameter and high-efficiency thermal power generating units, and a substantial increase in the power required for driving the feed pumps.
[0034] Feedwater pumps are key auxiliary equipment in thermal power generating units. Depending on the drive method, existing feedwater pumps mainly employ two types: electric feedwater pumps and steam-driven feedwater pumps. Electric feedwater pumps are driven by an electric motor, while steam-driven feedwater pumps are driven by a small steam turbine. For electric feedwater pumps, the power of the motor increases significantly, leading to a substantial rise in the unit's power consumption rate. Furthermore, the capacity and investment in speed control devices such as frequency converters for electric feedwater pumps also increase significantly. Simultaneously, the energy required to drive electric feedwater pumps must first be converted from mechanical energy to electrical energy by the main steam turbine generator unit, and then the electrical energy is converted back into mechanical energy for the feedwater pump motor. This involves multiple energy conversions between electrical and mechanical energy, resulting in relatively large energy conversion losses. Steam-driven feedwater pumps require the addition of a small steam turbine outside the main steam turbine of the thermal power generating unit, resulting in higher equipment investment costs. Furthermore, steam must be extracted from the high-parameter, high-efficiency main steam turbine to drive the small turbine, making the system more complex. At the same time, compared to the high efficiency of the main steam turbine, the efficiency of the small steam turbine driving the feedwater pump is relatively low. The extraction of steam to drive the small steam turbine also leads to steam heat energy loss, weakening the overall energy efficiency of the unit. This results in a problem of low energy utilization.
[0035] This utility model proposes a water supply system.
[0036] Please see Figure 1 In one embodiment of this utility model, the feedwater system includes a main steam turbine 1, a main feedwater pump 2, and a hydraulic coupling 3. The steam inlet of the main steam turbine 1 is connected to the superheater outlet, and the steam outlet of the main steam turbine 1 is connected to the condenser. The inlet of the main feedwater pump 2 is connected to the deaerator feedwater, and the outlet of the main feedwater pump 2 is connected to the boiler main feedwater. The hydraulic coupling 3 has a pump impeller shaft and a turbine shaft. The main shaft of the main steam turbine 1 is drivenly connected to the pump impeller shaft, and the turbine shaft is drivenly connected to the pump shaft of the main feedwater pump 2.
[0037] In this invention, the main steam turbine 1 directly powers the main feedwater pump 2, reducing intermediate energy conversion. The elimination of a small steam turbine improves steam utilization and overall energy efficiency. Simultaneously, by controlling the hydraulic coupling 3, the torque transmitted by the coupling 3 can be controlled by adjusting its level or oil volume without altering the main steam turbine 1's rotational speed. This allows for regulation of the water supply to the main feedwater pump 2, adjusting its real-time water volume. Overall, this improves both steam and energy utilization.
[0038] The main steam turbine 1 is the main steam turbine 1 of the power plant, not a separately installed small steam turbine. The main feedwater pump 2 is a mechanical pump that can be driven by external forces such as an electric motor; in this application, the main feedwater pump 2 is driven by the main steam turbine 1, and the hydraulic coupling 3 can transmit torque to control the speed of the main feedwater pump 2.
[0039] The water supply system also includes a generator set 4, which is located between the main steam turbine 1 and the hydraulic coupling 3. The main shaft of the main steam turbine 1 is driven to be connected to the main shaft of the generator set 4, and the main shaft of the generator set 4 is driven to be connected to the pump wheel shaft of the hydraulic coupling 3.
[0040] The generator set 4 is the main generator set 4 of the power plant, which can ensure the power generation of the generator set 4 and ensure the drive connection between the main steam turbine 1 and the main feedwater pump 2.
[0041] The main feedwater pump 2 is coaxially arranged with the high-parameter, high-efficiency main steam turbine generator set 4. The input end of the main steam turbine generator set 4 is coaxially connected to the end of the generator set 4. The main steam turbine generator set 4 efficiently converts steam thermal energy into mechanical energy to do work, driving the generator set 4 to rotate. This mechanical energy is then coaxially transmitted to the hydraulic coupler 3, driving the hydraulic coupler 3 to rotate. The output end of the hydraulic coupler 3 is connected to the main feedwater pump 2. The mechanical energy coaxially input from the main steam turbine generator set 4 to the hydraulic coupler 3 is further transmitted through the hydraulic coupler 3 to the main feedwater pump 2, which is connected to the output end of the hydraulic coupler 3. This mechanical energy directly drives the main feedwater pump 2 to rotate.
[0042] Since the main turbine generator set 4 has a constant speed, but the main feedwater pump 2 needs to be adjusted according to the load change of the unit, the hydraulic coupler 3 adjusts the speed of the main feedwater pump 2. Utilizing the speed regulation characteristics of the hydraulic coupler 3, when the speed of the turbine generator set 4 at the input end remains unchanged, the hydraulic coupler 3 adjusts the liquid filling volume of its working chamber, changes its output torque and output speed, and thus adjusts the speed of the main feedwater pump 2 connected to the output end of the hydraulic coupler 3, so as to meet the load regulation requirements of the main feedwater pump 2 and the turbine generator set 4.
[0043] There is no need to install a drive motor for the main feedwater pump 2, reducing the equipment investment cost of the motor and its matching variable frequency speed control device, lowering the power consumption rate, reducing the number of energy conversions, and reducing energy conversion losses. In addition, the main feedwater pump 2 is directly driven by the high-efficiency main steam turbine generator set 4, eliminating the need for a small steam turbine and its supporting auxiliary systems to drive the main feedwater pump 2, reducing system complexity and the equipment investment cost of the small steam turbine; at the same time, there is no need to extract steam from the main steam turbine 1 and send it to the relatively less efficient small steam turbine, the steam directly does work in the main steam turbine 1, improving the thermal energy utilization efficiency of the steam and enhancing the overall energy efficiency of the unit.
[0044] Please see Figure 1 Both the pump wheel shaft and the turbine shaft are equipped with clutches 5. By providing clutches 5, the clutches 5 between the pump wheel shaft and the turbine shaft can be disengaged when the hydraulic coupling 3 fails, thereby facilitating the maintenance of the generator set 4 while repairing the hydraulic coupling 3.
[0045] The clutch 5 includes a multi-plate electromagnetic clutch 5. The multi-plate electromagnetic clutch 5 is easy to operate and can quickly disconnect the connection between the pump wheel shaft and the turbine shaft in the event of a failure of the hydraulic coupling 3.
[0046] The hydraulic coupling 3 includes an electric hydraulic coupling 3. The torque transmitted by the hydraulic coupling 3 can be easily adjusted to regulate the water supply of the main water pump 2, improving operational convenience.
[0047] A flow meter 6 is installed at the outlet of the main water supply pump 2. The flow meter 6 can display the real-time water supply of the main water supply pump 2.
[0048] The flow meter 6 is located at the outlet of the main water supply pump 2 and can directly read the outlet flow of the main water supply pump 2. By reading the reading of the flow meter 6, the water supply of the main water supply pump 2 can be read, so as to adjust the torque of the hydraulic coupler 3 according to the required water supply, so that the water supply of the main water supply pump 2 can reach the required water supply.
[0049] The flow meter 6 can be an electromagnetic flow meter 6, which facilitates reading the value of the flow meter 6. It also facilitates transmitting the real-time flow detected by the flow meter 6 to the controller 7.
[0050] Please see Figure 2The water supply system also includes a controller 7, and the electric hydraulic coupler 3 and the flow meter 6 are both electrically connected to the controller 7. After receiving the real-time flow data from the flow meter 6, the controller 7 compares it with the required flow rate. When the real-time flow data from the flow meter 6 is less than the required flow rate, the controller increases the torque of the electric hydraulic coupler 3 to increase the speed of the main water supply pump 2, thereby increasing the water supply of the main water supply pump 2. When the real-time flow data from the flow meter 6 is higher than the required flow rate, the controller decreases the torque of the electric hydraulic coupler 3 to decrease the speed of the main water supply pump 2, thereby decreasing the water supply of the main water supply pump 2, thus ensuring the power generation of the generator set 4.
[0051] Please see Figure 2 The water supply system also includes a generator set 4 and a standby electric feedwater pump 8. The main shaft of the main turbine 1 is drivenly connected to the main shaft of the generator set 4, and the standby electric feedwater pump 8 is electrically connected to the generator set 4. By setting the standby electric feedwater pump 8, water supply can be guaranteed when the hydraulic coupling 3 fails and the main feedwater pump 2 cannot guarantee water supply.
[0052] The inlet of the standby electric feedwater pump 8 is used to connect to the deaerator feedwater, and the outlet of the standby electric feedwater pump 8 is used to connect to the boiler main feedwater.
[0053] The rated flow rate of the standby electric water supply pump 8 is not less than 30% of the rated flow rate of the main water supply pump 2. By setting a minimum rated flow rate of the standby electric water supply pump 8, the minimum water supply can be guaranteed to meet the requirements.
[0054] Furthermore, the rated flow rate of the standby electric water supply pump 8 is no more than 50% of the rated flow rate of the main water supply pump 2. This reduces the power consumption of the standby electric water supply pump 8, reduces its size requirements, and reduces the area it occupies.
[0055] Both the outlet of the standby electric water pump 8 and the outlet of the main water pump 2 are equipped with electric valves 9, which can control the opening and closing of the outlets of the standby electric water pump 8 and the main water pump 2.
[0056] The outlet of the electric water pump 8 is connected to the inlet of the flow meter 6. When the electric water pump 8 is started to supply water alone, the flow meter 6 can detect the water supply of the electric water pump 8. Only one of the main water pump 2 and the electric water pump 8 can operate at any given time, and the flow meter 6 can detect the water supply of both the main water pump 2 and the electric water pump 8 independently.
[0057] This utility model also proposes a power generation facility, which includes a water supply system. The specific structure of the water supply system is as described in the above embodiments. Since this power generation facility adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be described in detail here.
[0058] The power generation facilities may be part or all of the facilities of a power plant, and there is no limitation on this.
[0059] The above description is merely an exemplary embodiment of the present utility model and does not limit the patent scope of the present utility model. Any equivalent structural transformations made based on the technical concept of the present utility model and the contents of the present utility model specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present utility model.
Claims
1. A water supply system, characterized in that include: The main steam turbine has an inlet for connecting to the superheater outlet and an outlet for connecting to the condenser. The main feedwater pump has an inlet for connecting to the deaerator feedwater and an outlet for connecting to the boiler main feedwater. as well as, The hydraulic coupling has a pump wheel shaft and a turbine shaft, wherein the main shaft of the main steam turbine is driven to be connected to the pump wheel shaft, and the turbine shaft is driven to be connected to the pump shaft of the main feedwater pump.
2. The water service system of claim 1, wherein The water supply system also includes a generator set, which is located between the main steam turbine and the hydraulic coupler. The main shaft of the main steam turbine is driven to be connected to the main shaft of the generator set, and the main shaft of the generator set is driven to be connected to the pump wheel shaft of the hydraulic coupler.
3. The water service system of claim 2, wherein Both the pump wheel shaft and the turbine shaft are equipped with clutches.
4. The water service system of claim 3, wherein The clutch includes a multi-plate electromagnetic clutch.
5. The water delivery system of claim 1, wherein The hydraulic coupling includes an electro-hydraulic coupling.
6. The water delivery system of claim 5, wherein A flow meter is installed at the outlet of the main water supply pump.
7. The water delivery system of claim 6, wherein The water supply system also includes a controller, and the electric hydraulic coupler and the flow meter are both electrically connected to the controller.
8. The water delivery system of claim 1, wherein The water supply system also includes a generator set and a standby electric feedwater pump. The main shaft of the main steam turbine is driven to be connected to the main shaft of the generator set, and the standby electric feedwater pump is electrically connected to the generator set.
9. The water delivery system of claim 8, wherein The rated flow rate of the standby electric water supply pump is not less than 30% of the rated flow rate of the main water supply pump; and / or, The rated flow rate of the standby electric water supply pump shall not exceed 50% of the rated flow rate of the main water supply pump.
10. A power plant characterized in that, Includes the water supply system as described in any one of claims 1 to 9.