Feedwater pump governing system for thermal power production

Abstract

The application provides a feed water pump adjusting system for thermal power production, comprising: a feed water pump, which is arranged on a water supply pipe communicated with a thermal power production device, and has an input shaft connected with an output shaft of a speed increasing box, and the input shaft of the speed increasing box is connected with an output shaft of a motor; a high-voltage frequency converter, which is electrically connected with the motor, and is used for adjusting the rotating speed of the motor; an energy consumption monitoring device, which is arranged on an energy consumption monitoring pipeline communicated with the thermal power production device, and is used for monitoring the energy consumption of the thermal power production device and obtaining an energy consumption value; and a control unit, which is electrically connected with the feed water pump, the high-voltage frequency converter and the energy consumption monitoring device, and is used for receiving the energy consumption value and adjusting the output frequency and output voltage of the high-voltage frequency converter according to the energy consumption value to control the rotating speed of the motor, so as to realize the adjustment of the water supply amount of the feed water pump to the thermal power production device. The application improves the efficiency of the water supply of the feed water pump to the thermal power production device, and ensures the stable operation of the thermal power production process.

Description

Technical Field

[0001] This application relates to the field of thermoelectric production technology, and in particular to a feedwater pump regulation system for thermoelectric production. Background Technology

[0002] Feedwater pumps are an indispensable piece of equipment in cogeneration. Their main function is to transport water (at a certain temperature) from the deaerator tank to the boiler to meet the boiler's water requirements and ensure the normal operation of the boiler system and power generation efficiency. In cogeneration, the flow regulation of the feedwater pump is a key factor in ensuring the stable operation of the system.

[0003] Currently, the flow regulation of feedwater pumps in cogeneration processes is mainly achieved through speed-increasing hydraulic couplers. However, hydraulic couplers transmit torque through a liquid medium, which always results in slip (speed difference), causing some power to be lost as heat. In other words, the existing method of regulating the flow of feedwater pumps in cogeneration processes using speed-increasing hydraulic couplers is inefficient and wasteful of energy. Based on this, this application proposes a feedwater pump regulation system for cogeneration. Utility Model Content

[0004] This application provides a feedwater pump regulation system for thermal power generation to solve the technical problems described in the background art.

[0005] To solve the above-mentioned technical problems, this application adopts the following technical solution: This application provides a feedwater pump regulating system for thermal power generation, comprising: A water supply pump is installed on a water supply pipe connected to the thermal power generation equipment, and its input shaft is connected to the output shaft of a speed increaser, the input shaft of which is connected to the output shaft of a motor. A high-voltage frequency converter, which is electrically connected to the motor, is used to adjust the speed of the motor; An energy consumption monitoring device is installed on an energy consumption monitoring pipeline connected to the thermal power production equipment, and is used to monitor the energy consumption of the thermal power production equipment and obtain the energy consumption value; The control unit is electrically connected to the water pump, the high-voltage frequency converter, and the energy consumption monitoring device. It is used to receive the energy consumption value and adjust the output frequency and output voltage of the high-voltage frequency converter according to the energy consumption value to control the speed of the motor and thereby adjust the amount of water supplied by the water pump to the thermal power generation equipment.

[0006] Optionally, a pre-pump is provided between the motor and the speed increaser, the output shaft of the motor is connected to the input shaft of the pre-pump, and the output shaft of the pre-pump is connected to the input shaft of the speed increaser.

[0007] Optionally, the input terminal of the high-voltage frequency converter is connected to a power supply, which is 6kV.

[0008] Optionally, an electricity meter is provided between the high-voltage frequency converter and the power supply. The input terminal of the electricity meter is connected to the output terminal of the power supply, and the output terminal of the electricity meter is connected to the input terminal of the high-voltage frequency converter.

[0009] Optionally, there are multiple pieces of equipment for thermal power generation, and each piece of equipment corresponds to one of the water supply pumps, one of the speed increasers, one of the motors, one of the high-voltage frequency converters, and one of the energy consumption monitoring devices.

[0010] Optionally, each of the energy consumption monitoring devices includes a level gauge, a liquid flow meter, and a gas flow meter, and the level gauge, liquid flow meter, and gas flow meter corresponding to each of the energy consumption monitoring devices are electrically connected to the control unit; The level gauge is installed in the liquid chamber containing liquid in the thermal power production equipment and is used to detect the liquid level value in the liquid chamber. The liquid flow meter is installed on the fluid pipeline connected to the thermoelectric production equipment and is used to detect the flow rate of the fluid passing through the fluid pipeline. The gas flow meter is installed on the gas pipeline connected to the thermal power generation equipment and is used to detect the flow rate of the gas passing through the gas pipeline.

[0011] The feedwater pump regulation system for thermal power generation provided in this application monitors the energy consumption of the thermal power generation equipment using energy consumption monitoring equipment, obtains the energy consumption value, and then transmits the energy consumption value to the control unit. The control unit adjusts the output frequency and voltage of the high-voltage frequency converter based on the received energy consumption value to control the motor speed. This achieves regulation of the water supply from the feedwater pump to the thermal power generation equipment. The high-voltage frequency converter, by adjusting the output frequency and voltage, prevents the motor from operating at full load for extended periods. In other words, it can adjust the motor speed and torque in a timely manner according to the actual operating conditions of the thermal power equipment during thermal power generation, significantly reducing the motor's energy consumption. Furthermore, a speed increaser is installed between the motor and the feedwater pump. The speed increaser uses direct mechanical gear transmission, eliminating slip power loss and ensuring precise speed control. It also avoids the speed fluctuation problems associated with hydraulic couplings, effectively reducing energy consumption. In other words, compared with the existing technology, this application can achieve motor speed regulation by combining a high-voltage frequency converter and a speed increaser. Furthermore, the water supply from the feed water pump to the thermal power production equipment can be precisely adjusted during the motor speed regulation process, so that the water supply can meet the dynamic needs of the thermal power production equipment. This improves the efficiency of water supply to the thermal power production equipment through the feed water pump and ensures the stable operation of the thermal power production process. Attached Figure Description

[0012] To more clearly illustrate the technical solutions in the embodiments of this application 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 some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0013] Figure 1 A schematic diagram of the structure of a feedwater pump regulating system for thermal power generation provided in an embodiment of this application; Figure 2 A schematic diagram of the structure of a feedwater pump regulating system for thermal power generation provided in another embodiment of this application; Figure 3 A schematic diagram of the structure of a feedwater pump regulating system for thermal power generation provided in another embodiment of this application; Figure 4 A schematic diagram of the structure of a feedwater pump regulating system for thermal power generation provided in another embodiment of this application.

[0014] In the diagram: 100, water pump; 200, thermal power generation equipment; 201, water supply pipe; 202, liquid chamber; 203, liquid pipeline; 204, gas pipeline; 300, speed increaser; 400, motor; 500, high-voltage frequency converter; 600, energy consumption monitoring equipment; 601, level gauge; 602, liquid flow meter; 603, gas flow meter; 700, control unit; 800, pre-pump; 900, power supply; 1000, electricity meter. Detailed Implementation

[0015] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions in the embodiments of this application are described clearly and completely below. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are also within the scope of protection of this application.

[0016] refer to Figures 1 to 4 This application provides a feedwater pump regulating system for thermal power generation, comprising: A water supply pump 100 is installed on a water supply pipe 201 that is connected to the thermal power generation equipment 200, and its input shaft is connected to the output shaft of a speed increaser 300, the input shaft of which is connected to the output shaft of a motor 400; wherein, the thermal power generation equipment 200 can be a boiler.

[0017] A high-voltage frequency converter 500 is electrically connected to the motor 400 and is used to regulate the speed of the motor 400. The high-voltage frequency converter 500 allows for adjustable motor speed, preventing the motor 400 from operating at full load for extended periods. This enables timely adjustments to the motor 400's speed and torque based on the actual operating conditions of the thermal power generation equipment 200 during the thermal power production process, significantly reducing the motor 400's energy consumption. Furthermore, the high-voltage frequency converter's output voltage is 0-6kV, allowing direct drive of the motor 400 without the need for a voltage booster, simplifying the system structure. Its output power can be 0-50 Hz. Since the motor 400, water pump 100, and other loads in thermal power generation need to adjust their speeds according to changes in heating or power generation loads, the high-voltage frequency converter 500's frequency can be freely adjusted from 0-50Hz, thus enabling speed regulation of the motor 400 and, consequently, more precise flow regulation of the water pump 100.

[0018] An energy consumption monitoring device 600 is installed on an energy consumption monitoring pipeline connected to the thermal power production equipment 200. The device is used to monitor the energy consumption of the thermal power production equipment 200 and obtain energy consumption values. There are multiple energy consumption values, such as liquid level value, liquid flow rate value and gas flow rate value, which depend on the energy consumption parameters to be monitored. This application will not elaborate on them further.

[0019] The control unit 700 is electrically connected to the water pump 100, the high-voltage frequency converter 500, and the energy consumption monitoring device 600. It receives energy consumption values ​​and adjusts the output frequency and voltage of the high-voltage frequency converter 500 based on these values ​​to control the speed of the motor 400, thereby regulating the amount of water supplied by the water pump 100 to the thermal power generation equipment 200. The control unit 700 is a distributed control system. A distributed control system is a new generation of instrument control system based on a microprocessor, employing the design principles of distributed control functions, centralized display and operation, and a balance between decentralized autonomy and comprehensive coordination. Specifically, it adopts the basic design concept of distributed control and centralized operation and management, using a multi-level, hierarchical, cooperative, and autonomous structure. Its main characteristics are centralized management and distributed control. Currently, distributed control systems are widely used in various industries such as power, metallurgy, and petrochemicals. Therefore, the control technology and principles of distributed control systems are existing technologies, and this application will not elaborate on them here.

[0020] The feedwater pump regulation system for thermal power generation provided in this application monitors the energy consumption of the thermal power generation equipment 200 using an energy consumption monitoring device 600, obtains the energy consumption value, and then transmits this value to a control unit 700. The control unit 700 adjusts the output frequency and voltage of the high-voltage frequency converter 500 based on the received energy consumption value to control the speed of the motor 400. This achieves regulation of the water supply from the feedwater pump 100 to the thermal power generation equipment 200. Furthermore, the high-voltage frequency converter 500, by adjusting its output frequency and voltage, prevents the motor 400 from operating at full load for extended periods. This allows for timely adjustment of the motor 400's speed and torque based on the actual operating conditions of the thermal power generation equipment 200 during thermal power generation, significantly reducing the motor 400's energy consumption. In addition, a speed increaser 300 is installed between the motor 400 and the feedwater pump 100. The speed increaser 300 uses direct mechanical gear transmission, eliminating slip power loss and ensuring precise speed control. It also avoids the speed fluctuation problems associated with hydraulic couplings, effectively reducing energy consumption. In other words, compared with the prior art, this application, by combining the high-voltage frequency converter 500 and the speed increaser 300, can achieve the adjustment of the speed of the motor 400. Furthermore, through the adjustment of the speed of the motor 400, the water supply from the water pump 100 to the thermal power production equipment 200 can be precisely adjusted, so that the water supply can meet the dynamic needs of the thermal power production equipment 200. This improves the efficiency of water supply from the water pump 400 to the thermal power production equipment 200 and ensures the stable operation of the thermal power production process.

[0021] In some embodiments, reference Figure 2 In this application, a pre-pump 800 is provided between the motor 400 and the speed increaser 300. The output shaft of the motor 400 is connected to the input shaft of the pre-pump 800, and the output shaft of the pre-pump 800 is connected to the input shaft of the speed increaser 300.

[0022] In the above embodiments, the feed water is pre-pressurized by the pre-pump 800 to ensure that the water entering the feed water pump 100 has sufficient pressure, so that the water pressure entering the feed water pump 100 is much higher than the saturated vapor pressure at that water temperature, thereby effectively avoiding cavitation at the impeller of the feed water pump 100 and thus improving the service life of the feed water pump 100.

[0023] In some embodiments, reference Figure 3 The input terminal of the high-voltage frequency converter 500 in this application is connected to a power supply 900, which is 6kV.

[0024] In the above embodiment, the power supply 900 provides stable and controllable high-frequency AC power to the high-voltage frequency converter 500 to achieve voltage transformation, electrical isolation, and energy transfer, thereby ensuring the flow regulation of the feedwater pump 100 during the thermal power production process and thus ensuring the stable operation of the thermal power production process. In addition, the 6kV power supply has the following advantages: 1) The 6kV power supply 900 can directly or after being stepped up by a transformer to meet the needs of high-voltage loads, reducing the losses and complexity of multi-stage conversion. 2) The 6kV power supply 900 is a common voltage level in industrial systems; selecting this voltage ensures compatibility with existing infrastructure (such as cables and switchgear), thereby reducing equipment customization costs and maintenance difficulties.

[0025] In some embodiments, reference Figure 3 In this application, an electricity meter 1000 is provided between the high-voltage frequency converter 500 and the power supply 900. The input terminal of the electricity meter 1000 is connected to the output terminal of the power supply 900, and the output terminal of the electricity meter 1000 is connected to the input terminal of the high-voltage frequency converter 500.

[0026] In the above embodiments, the data displayed by the electricity meter 1000 can reflect the load changes and power quality (such as voltage and current fluctuations) of the high-voltage frequency converter 500, assisting in the diagnosis of equipment faults or power grid anomalies, facilitating timely optimization of the control strategy of the high-voltage frequency converter 500, and reducing system operating costs.

[0027] In some embodiments, there are multiple thermal power generation devices 200 in this application, each corresponding to a water supply pump 100, a speed increaser 300, a motor 400, a high-voltage frequency converter 500, and an energy consumption monitoring device 600. The thermal power generation device 200 may be a boiler.

[0028] In the above embodiments, since the thermal power plant uses more than one thermal power production equipment 200, and the feed water pump 100, speed increaser 300, motor 400, high-voltage frequency converter 500 and energy consumption monitoring equipment 600 corresponding to multiple thermal power production equipment 200 are all regulated by the control unit 700, thereby realizing the linkage control of the feed water pump 100 corresponding to multiple thermal power production equipment 200, and automatically tracking and adjusting the water supply of the feed water pump 100 to the thermal power production equipment 200 according to the load changes of the thermal power production equipment 200 monitored by the energy consumption monitoring equipment 600, thereby reducing the operational pressure on the operators.

[0029] In some embodiments, reference Figure 4Each energy consumption monitoring device 600 in this application includes a level gauge 601, a liquid flow meter 602, and a gas flow meter 603. The level gauge 601, liquid flow meter 602, and gas flow meter 603 corresponding to each energy consumption monitoring device 600 are electrically connected to the control unit 700. The thermal power generation equipment 200 in this application can be a boiler, and the energy consumption monitoring device 600 includes, but is not limited to, the level gauge 601, liquid flow meter 602, and gas flow meter 603. The level gauge 601, liquid flow meter 602, and gas flow meter 603 are commonly used energy consumption monitoring devices 600 in the thermal power generation equipment 200. That is to say, the specific energy consumption monitoring device 600 can be set according to the specific type of thermal power generation equipment 200, and this application does not specifically limit it.

[0030] A level gauge 601 is installed in the liquid chamber 202 of the thermal power production equipment 200, which contains liquid, to detect the liquid level value in the liquid chamber 202. The level gauge 601 transmits the detected liquid level value in the liquid chamber 202 of the thermal power production equipment 200 to the control unit 700, and the control unit 700 adjusts the water supply volume and water supply rate of the water pump 100 in a timely manner based on the received liquid level value.

[0031] A liquid flow meter 602 is installed on a fluid pipeline 203 connected to the thermal power generation equipment 200 to detect the flow rate of the fluid passing through the fluid pipeline 203. The liquid flow meter 602 transmits the detected flow rate of the fluid in the fluid pipeline 203 connected to the thermal power generation equipment 200 to the control unit 700, and the control unit 700 adjusts the water supply volume and water supply rate of the water pump 100 in a timely manner based on the received flow rate.

[0032] A gas flow meter 603 is installed on a gas pipeline 204 connected to the thermal power generation equipment 200 to detect the flow rate of gas passing through the gas pipeline 204. The gas flow meter 603 transmits the detected gas flow rate from the gas pipeline 204 connected to the thermal power generation equipment 200 to a control unit 700, which then adjusts the water supply volume and rate of the water pump 100 based on the received gas flow rate.

[0033] In the above embodiment, the control unit 700 makes a comprehensive judgment based on the liquid level value monitored by the liquid level gauge 601, the fluid flow rate value monitored by the liquid flow meter 602, and the gas flow rate value monitored by the gas flow meter 603, and then adjusts the flow rate of the water supply pump 100 so that the water supply of the water supply pump 100 can meet the water demand of the thermal power production equipment 200 in a timely manner, thereby improving the accuracy and stability of the thermal power production process.

[0034] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A feedwater pump regulating system for thermal power generation, characterized in that, include: A water pump (100) is installed on a water supply pipe connected to the thermal power generation equipment (200), and its input shaft is connected to the output shaft of a speed increaser (300), the input shaft of which is connected to the output shaft of a motor (400); A high-voltage frequency converter (500) is electrically connected to the motor (400) and is used to adjust the speed of the motor (400); An energy consumption monitoring device (600) is installed on an energy consumption monitoring pipeline connected to the thermal power production equipment (200) for monitoring the energy consumption of the thermal power production equipment (200) and obtaining the energy consumption value. The control unit (700) is electrically connected to the water pump (100), the high-voltage frequency converter (500) and the energy consumption monitoring device (600), and is used to receive the energy consumption value and adjust the output frequency and output voltage of the high-voltage frequency converter (500) according to the energy consumption value to control the speed of the motor (400) and thereby realize the adjustment of the amount of water supplied by the water pump (100) to the thermal power generation equipment (200).

2. The feedwater pump regulating system for thermal power generation according to claim 1, characterized in that, A pre-pump (800) is provided between the motor (400) and the speed increaser (300). The output shaft of the motor (400) is connected to the input shaft of the pre-pump (800), and the output shaft of the pre-pump (800) is connected to the input shaft of the speed increaser (300).

3. The feedwater pump regulating system for thermal power generation according to claim 1, characterized in that, The input terminal of the high-voltage frequency converter (500) is connected to a power supply (900), which is 6kV.

4. The feedwater pump regulating system for thermal power generation according to claim 3, characterized in that, An electricity meter (1000) is provided between the high-voltage frequency converter (500) and the power supply (900). The input terminal of the electricity meter (1000) is connected to the output terminal of the power supply (900), and the output terminal of the electricity meter (1000) is connected to the input terminal of the high-voltage frequency converter (500).

5. The feedwater pump regulating system for thermal power generation according to claim 1, characterized in that, There are multiple thermal power generation equipment (200), and each of the multiple thermal power generation equipment (200) corresponds to a water supply pump (100), a speed increaser (300), a motor (400), a high-voltage frequency converter (500), and an energy consumption monitoring device (600).

6. The feedwater pump regulating system for thermal power generation according to claim 5, characterized in that, Each of the energy consumption monitoring devices (600) includes a level gauge (601), a liquid flow meter (602), and a gas flow meter (603), and the level gauge (601), the liquid flow meter (602), and the gas flow meter (603) corresponding to each of the energy consumption monitoring devices (600) are electrically connected to the control unit (700); The level gauge (601) is installed in the liquid chamber (202) containing liquid in the thermoelectric production equipment (200) and is used to detect the liquid level value in the liquid chamber (202); The liquid flow meter (602) is installed on the fluid pipeline (203) connected to the thermoelectric production equipment (200) and is used to detect the flow rate of the fluid passing through the fluid pipeline (203); The gas flow meter (603) is installed on the gas pipeline (204) connected to the thermoelectric production equipment (200) and is used to detect the flow rate of the gas passing through the gas pipeline (204).

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