Energy-saving device and method for enabling steam extraction to participate in primary frequency modulation
By designing a device including a steam turbine main generator set, a steam turbine water supply unit and a water supply heating pipeline, the steam volume and air intake valve are adjusted by using the water supply turbine and auxiliary generator sets to adjust the steam volume and air intake valves, the problem of difficulty in fully opening the air intake valves during the first frequency regulation of the steam turbine generator set is solved, and the economy and frequency regulation efficiency of the unit are improved.
Patent Information
- Application Number
- CN202510022038.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-07
- Publication Date
- 2025-05-23
AI Technical Summary
When the steam turbine generator set meets the unit's primary frequency regulation performance requirements, it is difficult for the prior art to achieve full opening of the intake valve, resulting in the unit being unable to operate with sliding pressure, which sacrifices economy, especially under low loads, the valve throttling loss is greater.
设计了一种节能型抽汽参与一次调频的装置，包括汽轮主发电机组、汽轮给水机组和给水加热管线。通过给水汽轮机与汽轮主发电机组的排气管线连接，利用给水加热管线和辅助发电机组，调节进气阀门和给水泵的转速，实现蒸汽量的动态调整。
It improves the economical operation of the unit, reduces valve throttling losses, and ensures the economical operation and efficient frequency regulation capabilities of the unit at low loads.
Smart Images
Figure CN120033723A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of power generation frequency modulation, and in particular relates to an energy-saving steam extraction device and method for participating in primary frequency modulation. Background Art
[0002] Generator sets connected to the grid are generally required to have a primary frequency regulation function, which can quickly adjust the unit load within a certain amplitude range and at a certain inequality rate according to changes in the grid frequency, so that the power output of the generator set matches the load of the grid, preventing overload or underload, thereby ensuring the stable operation of the grid.
[0003] The most economical operation mode of a steam turbine generator set is to fully open the intake valve of the steam turbine and operate the unit at sliding pressure. However, since the intake valve is fully open, the intake valve loses its ability to continue to open wider and quickly increase the load of the unit (i.e., the ability to increase the output load during primary frequency regulation. When the load of the power grid increases, the output load (electric energy) of the generator set needs to be increased. The increase in the intake volume of the steam turbine can increase the output load of the generator set). How to meet the performance requirements of the power grid dispatching for the primary frequency regulation of the unit is a big problem. In order to meet the performance requirements of primary frequency regulation and increased output load, the intake valve of the existing steam turbine is usually not fully opened, and the valve throttling operation mode is adopted, which makes the unit unable to operate at sliding pressure, sacrificing a large degree of economy, especially under low load, the throttling loss of the valve is greater. Summary of the invention
[0004] In view of this, the object of the present invention is to provide an energy-saving device and method for extracting steam to participate in primary frequency regulation, so as to improve the economy of unit operation.
[0005] The present invention solves the above problems by the following technical means: An energy-saving device for extracting steam to participate in primary frequency modulation includes a steam turbine main generator set, a steam turbine feedwater unit and a feedwater heating pipeline. The steam turbine feedwater unit includes a feedwater turbine and a feedwater pump that are transmission-connected. The air intake end of the feedwater turbine is connected to the exhaust pipeline of the steam turbine main generator set through the feedwater turbine air intake pipeline, and the feedwater heating pipeline is also connected to the exhaust pipeline of the steam turbine main generator set.
[0006] After the steam performs work in the main generator set of the steam turbine, it is discharged through the exhaust pipeline. Most of the steam flows back to the boiler for heating, and then circulates into the main generator set of the steam turbine to perform work; part of it flows to the feedwater turbine to perform work, so that the feedwater turbine drives the feedwater pump to start, and supplies water to the boiler through the feedwater pump; the other part flows to the feedwater heating pipeline to heat the supply water.
[0007] Furthermore, a feedwater turbine air intake valve is provided on the feedwater turbine air intake pipeline.
[0008] Furthermore, a water heating air intake valve is provided on the water heating pipeline.
[0009] Furthermore, a heater is provided on the water heating pipeline.
[0010] Steam is transported through the feedwater heating pipeline and combined with the heater to heat the feed water delivered to the boiler; the feedwater heating air inlet valve can regulate the steam delivery volume of the feedwater heating pipeline.
[0011] Furthermore, it also includes an auxiliary generator set drivingly connected to the feedwater steam turbine.
[0012] Part of the output power of the feedwater turbine is used to drive the feedwater pump, and part is used to assist the generator set in generating electricity. In actual operation, the speed of the feedwater pump usually has to meet the set constant speed. When the output power of the feedwater turbine fluctuates based on its intake steam flow, the power generation of the auxiliary generator set is adjusted in real time to maintain the feedwater pump at a constant speed.
[0013] An energy-saving steam extraction method for participating in primary frequency regulation using the above-mentioned device, when the steam turbine main generator set is operating normally, the air intake valve of the steam turbine main generator set is adjusted to make the steam turbine main generator set operate at sliding pressure; at this time, the air intake valve of the feedwater turbine is fully opened, and the rotation speed of the feedwater pump is balanced by the power generation size of the auxiliary generator set, and the feedwater heating air intake valve is also fully opened to ensure the feedwater temperature; when primary frequency regulation is required to reduce the output power of the steam turbine main generator set, the air intake valve of the steam turbine main generator set is adaptively closed; when primary frequency regulation is required to increase the output power of the steam turbine main generator set, the air intake valve of the feedwater turbine and the feedwater heating air intake valve are adaptively closed to increase the amount of steam circulating into the steam turbine main generator set to do work, thereby increasing the output power of the steam turbine main generator set; after the boiler load is increased, the small feedwater turbine air intake valve and the feedwater heating air intake valve are fully opened to maintain the economic operation of the unit and improve the economy of the unit operation.
[0014] Beneficial effects of the present invention: The present application provides an energy-saving device and method for extracting steam to participate in primary frequency modulation, the device includes a steam turbine main generator set, a steam turbine feedwater unit and a feedwater heating pipeline, the steam turbine feedwater unit includes a feedwater steam turbine and a feedwater pump connected in a transmission manner, the air intake end of the feedwater steam turbine is connected to the exhaust pipeline of the steam turbine main generator set through the feedwater steam turbine air intake pipeline, and the feedwater heating pipeline is also connected to the exhaust pipeline of the steam turbine main generator set. The device and method of the present application improve the economic efficiency of the unit operation. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.
[0016] Figure 1 It is a schematic diagram of a preferred embodiment of the present invention. DETAILED DESCRIPTION
[0017] The present invention will be described in detail below with reference to the accompanying drawings. Figure 1 As shown: the energy-saving steam extraction device participating in primary frequency modulation of the present invention includes a steam turbine main generator set 1, a steam turbine feed water unit and a feed water heating pipeline 3, the steam turbine feed water unit includes a feed water turbine 9 and a feed water pump 7 connected by transmission, the air intake end of the feed water turbine is connected to the exhaust pipeline 2 of the steam turbine main generator set through the feed water turbine air intake pipeline 6, and the feed water heating pipeline is also connected to the exhaust pipeline of the steam turbine main generator set.
[0018] After the steam performs work in the main generator set of the steam turbine, it is discharged through the exhaust pipeline. Most of the steam flows back to the boiler for heating, and then circulates into the main generator set of the steam turbine to perform work; part of it flows to the feedwater turbine to perform work, so that the feedwater turbine drives the feedwater pump to start, and supplies water to the boiler through the feedwater pump; the other part flows to the feedwater heating pipeline to heat the supply water.
[0019] The feedwater turbine air intake pipeline is provided with a feedwater turbine air intake valve 8 .
[0020] The water heating pipeline is provided with a water heating air intake valve 4 and a heater 5 .
[0021] Steam is transported through the feedwater heating pipeline and combined with the heater to heat the feed water delivered to the boiler; the feedwater heating air inlet valve can regulate the steam delivery volume of the feedwater heating pipeline.
[0022] It also includes an auxiliary generator set 10 drivingly connected to the feedwater steam turbine.
[0023] Part of the output power of the feedwater turbine is used to drive the feedwater pump, and part is used to assist the generator set in generating electricity. In actual operation, the speed of the feedwater pump usually has to meet the set constant speed. When the output power of the feedwater turbine fluctuates based on its intake steam flow, the power generation of the auxiliary generator set is adjusted in real time to maintain the feedwater pump at a constant speed.
[0024] An energy-saving steam extraction method for participating in primary frequency regulation using the above-mentioned device, when the steam turbine main generator set is operating normally, the air intake valve of the steam turbine main generator set is adjusted to make the steam turbine main generator set operate at sliding pressure; at this time, the air intake valve of the feedwater turbine is fully opened, and the rotation speed of the feedwater pump is balanced by the power generation size of the auxiliary generator set, and the feedwater heating air intake valve is also fully opened to ensure the feedwater temperature; when primary frequency regulation is required to reduce the output power of the steam turbine main generator set, the air intake valve of the steam turbine main generator set is adaptively closed; when primary frequency regulation is required to increase the output power of the steam turbine main generator set, the air intake valve of the feedwater turbine and the feedwater heating air intake valve are adaptively closed to increase the amount of steam circulating into the steam turbine main generator set to do work, thereby increasing the output power of the steam turbine main generator set; after the boiler load is increased, the small feedwater turbine air intake valve and the feedwater heating air intake valve are fully opened to maintain the economic operation of the unit and improve the economy of the unit operation.
[0025] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.
Claims
1. An energy-saving steam extraction device for primary frequency modulation, characterized in that: It includes a steam turbine main generator set, a steam turbine feedwater unit and a feedwater heating pipeline. The steam turbine feedwater unit includes a feedwater turbine and a feedwater pump which are transmission-connected. The air inlet end of the feedwater turbine is connected to the exhaust pipeline of the steam turbine main generator set through the feedwater turbine air inlet pipeline. The feedwater heating pipeline is also connected to the exhaust pipeline of the steam turbine main generator set.
2. The energy-saving steam extraction device for primary frequency modulation according to claim 1 is characterized in that: The feedwater turbine air intake pipeline is provided with a feedwater turbine air intake valve.
3. The energy-saving steam extraction device for primary frequency modulation according to claim 2 is characterized in that: The water heating pipeline is provided with a water heating air intake valve.
4. The energy-saving steam extraction device for primary frequency modulation according to claim 3 is characterized in that: The water supply heating pipeline is provided with a heater.
5. The energy-saving steam extraction device for primary frequency modulation according to claim 4 is characterized in that: It also includes an auxiliary generator set drivingly connected to the feedwater steam turbine.
6. An energy-saving steam extraction method for primary frequency modulation using the device as claimed in claim 5, characterized in that: When the main steam turbine generator set is operating normally, adjust the air intake valve of the main steam turbine generator set to make the main steam turbine generator set run at sliding pressure; at this time, the air intake valve of the feedwater turbine is fully opened, and the speed of the feedwater pump is balanced by the power generation of the auxiliary generator set, and the feedwater heating air intake valve is also fully opened to ensure the feedwater temperature; when a frequency regulation is required to reduce the output power of the main steam turbine generator set, the air intake valve of the main steam turbine generator set is adaptively closed; when a frequency regulation is required to increase the output power of the main steam turbine generator set, the air intake valve of the feedwater turbine and the feedwater heating air intake valve are adaptively closed to increase the amount of steam circulating into the main steam turbine generator set to do work and increase the output power of the main steam turbine generator set; after the boiler load is increased, fully open the small feedwater turbine air intake valve and the feedwater heating air intake valve to maintain the economical operation of the unit.