Dynamically reconfigured steam turbine power generating unit and method of operation

Abstract

The present invention provides a dynamically reconfigured steam turbine power generating unit and an operating method thereof, the steam turbine power generating unit includes a high pressure compensation pressure stage and / or an intermediate pressure compensation pressure stage, and the operating load mode of the steam turbine unit is firstly divided, and in the high load mode, the normal high pressure cylinder and the intermediate pressure cylinder are put into operation, and the high pressure compensation pressure stage and / or the intermediate pressure compensation pressure stage are idled or stopped, and in the low load mode, the high pressure compensation pressure stage is operated in series with the high pressure cylinder and / or the intermediate pressure compensation pressure stage is operated in series with the intermediate pressure cylinder. In the flow system, the pressure stages are connected in series to increase the work share, and the high operating pressure of the unit is maintained by pressure transmission. According to the operating load mode, the flow state of the turbine unit is dynamically reconfigured, so that the problem of the sudden drop in energy efficiency caused by the drop in the main reheat steam operating pressure when the steam turbine unit is in the medium and low load mode is avoided, and the adaptability of the operating conditions of the steam turbine unit is improved.

Description

[Technical Field]

[0001] The present invention relates to the technical field of steam turbine power generation, and more particularly to a dynamically reconfigured steam turbine power generation unit and method of operation. [Background technology]

[0002] The "dual carbon" strategy promotes the construction of a new power system dominated by new energy sources. As large-scale, randomly fluctuating new energy sources such as photovoltaics and wind power are integrated into the grid, coal-fired power generation, the primary power source, is being forced to fully participate in the adjustment process. The design of coal-fired thermal power plants primarily considers their operating efficiency at full load. During the adjustment process, the power generation efficiency of units operating at medium and low loads deteriorates dramatically. Compared to full load operation, coal consumption at 30% full load for typical coal-fired thermal power plants increases by 30-40g / kW·h. The direct cause of this is that under the "constant-smooth-constant" operating mode, the main steam pressure drops significantly at medium and low loads, reducing the circulation efficiency of the direct thermal power system and increasing the steam turbine's flow loss.

[0003] In the past, once a steam turbine unit was manufactured and installed, its structural connection state was standardized, and each pressure cylinder could only operate in a predetermined state. Because each pressure cylinder was designed for full load mode, when the steam turbine unit operated in medium or low load mode, the main steam operating pressure would drop, making it impossible to reconstruct the steam turbine unit structure, ultimately resulting in a sharp decline in energy efficiency during the depth adjustment process. Summary of the Invention

[0004] In order to overcome the shortcomings of the prior art, an object of the present invention is to provide a dynamically reconfigured steam turbine power generation unit and an operating method for solving the problem that, when a steam turbine unit in the prior art operates in a medium or low load mode, its structural connection state cannot be adaptively reconfigured in response to changes in the load mode, resulting in a sudden deterioration in energy efficiency.

[0005] In order to solve the above problems, the technical solution adopted by the present invention is as follows.

[0006] A first aspect provides a dynamically reconfigured steam turbine power generation unit including a boiler, a first rotating shaft, a high-pressure cylinder, and an intermediate-pressure cylinder, wherein a main steam outlet end of the boiler is connected to a steam inlet end piping of the high-pressure cylinder by a main steam pipe, the main steam pipe being provided with a main valve, an exhaust outlet end of the high-pressure cylinder is connected to a reheat steam inlet end piping of the boiler by a cold reheat steam pipe, and a reheat steam outlet end of the boiler is connected to a steam inlet end piping of the intermediate-pressure cylinder by the reheat steam pipe, the reheat steam pipe being provided with a fourth valve, and the high-pressure cylinder and the intermediate-pressure cylinder are sequentially arranged along a central axis direction of the first rotating shaft.

[0007] The dynamically reconfigured steam turbine power generation unit further includes a second rotating shaft, a high-pressure compensating pressure stage, and an energy conversion device, wherein the high-pressure compensating pressure stage and the energy conversion device are sequentially arranged along the central axial direction of the second rotating shaft, a first valve is provided between the main valve and the high-pressure cylinder, and a second valve is provided between the main valve and the high-pressure compensating pressure stage, and the exhaust outlet end of the high-pressure compensating pressure stage is connected to the steam outlet end piping of the first valve by a third valve, and then further connected to the steam inlet end piping of the high-pressure cylinder.

[0008] A second aspect provides a dynamically reconfigured steam turbine power generation unit, which includes a boiler, a first rotating shaft, a high-pressure cylinder, and an intermediate-pressure cylinder, wherein a main steam outlet end of the boiler is connected to a steam inlet end piping of the high-pressure cylinder by a main steam pipe, the main steam pipe being provided with a main valve, an exhaust outlet end of the high-pressure cylinder is connected to a reheat steam inlet end piping of the boiler by a cold reheat steam pipe, and a reheat steam outlet end of the boiler is connected to a steam inlet end piping of the intermediate-pressure cylinder by a reheat steam pipe, the reheat steam pipe being provided with a fourth valve, and the high-pressure cylinder and the intermediate-pressure cylinder are sequentially arranged along a central axis direction of the first rotating shaft.

[0009] The dynamically reconfigured steam turbine power generation unit further includes a second rotating shaft, an intermediate pressure compensating pressure stage, and an energy conversion device, wherein the intermediate pressure compensating pressure stage and the energy conversion device are sequentially arranged along the central axis direction of the second rotating shaft, and the steam inlet end of the intermediate pressure compensating pressure stage is connected to the steam inlet end piping of the fourth valve by a fifth valve, and the exhaust outlet end of the intermediate pressure compensating pressure stage is connected to the steam outlet end piping of the fourth valve by a sixth valve, and then further connected to the steam inlet end piping of the intermediate pressure cylinder.

[0010] A third aspect provides a dynamically reconfigured steam turbine power generation unit, which includes a boiler, a first rotating shaft, a high-pressure cylinder, and an intermediate-pressure cylinder, wherein a main steam outlet end of the boiler is connected to a steam inlet end piping of the high-pressure cylinder by a main steam pipe, the main steam pipe being provided with a main valve, an exhaust outlet end of the high-pressure cylinder is connected to a reheat steam inlet end piping of the boiler by a cold reheat steam pipe, and a reheat steam outlet end of the boiler is connected to a steam inlet end piping of the intermediate-pressure cylinder by a reheat steam pipe, the reheat steam pipe being provided with a fourth valve, and the high-pressure cylinder and the intermediate-pressure cylinder are sequentially arranged along a central axial direction of the first rotating shaft.

[0011] The dynamically reconfigured steam turbine power generation unit further includes a second rotating shaft, a high-pressure compensating pressure stage, an intermediate-pressure compensating pressure stage, and an energy conversion device, which are sequentially arranged along the central axis of the second rotating shaft, a first valve being provided between the main valve and the high-pressure cylinder, and a second valve being provided between the main valve and the high-pressure compensating pressure stage, an exhaust outlet end of the high-pressure compensating pressure stage being connected to a steam outlet end piping of the first valve by a third valve and then to a steam inlet end piping of the high-pressure cylinder, a steam inlet end of the intermediate-pressure compensating pressure stage being connected to a steam inlet end piping of the fourth valve by a fifth valve, and an exhaust outlet end of the intermediate-pressure compensating pressure stage being connected to a steam outlet end piping of the fourth valve by a sixth valve and then to a steam inlet end piping of the intermediate-pressure cylinder.

[0012] Furthermore, the load factor at the first state reconfiguration point of the steam turbine power generation unit is set to n%, and the flow area of ​​the high pressure compensation pressure stage is set to 0.4n% to 1.5n% of the flow area of ​​the high pressure cylinder.

[0013] Furthermore, the load factor of the second state reconfiguration point of the steam turbine power generation unit is set to m%, and the flow area of ​​the intermediate pressure compensation pressure stage is set to 0.4m% to 1.5m% of the flow area of ​​the intermediate pressure cylinder.

[0014] A fourth aspect provides an operating method for the dynamically reconfigured steam turbine power generation unit according to the first or third aspect, in which, in a high load mode, the first valve is opened, the second valve and the third valve are closed, and the high pressure compensation pressure stage is idled or stopped.

[0015] In a low load mode, the second and third valves are opened and the first valve is closed, causing the high pressure compensating pressure stage to operate in series with the high pressure cylinder.

[0016] A fifth aspect provides an operating method for a dynamically reconfigured steam turbine power generation unit according to the second or third aspect, in which, in a high load mode, the fourth valve is opened, the fifth and sixth valves are closed, and the intermediate pressure compensator pressure stage is idled or stopped.

[0017] In a low load mode, the fifth and sixth valves are opened and the fourth valve is closed, causing the medium pressure compensating pressure stage to operate in series with the medium pressure cylinder.

[0018] A sixth aspect provides an operating method for the dynamically reconfigured steam turbine power generation unit according to the third aspect, in which, in a high load mode, the first and fourth valves are opened and the second, third, fifth and sixth valves are closed, and the high pressure compensating pressure stage and the intermediate pressure compensating pressure stage are idled or stopped.

[0019] In a low load mode, the second, third, fifth, and sixth valves are opened, the first and fourth valves are closed, the high pressure compensation pressure stage is operated in series with the high pressure cylinder, and the medium pressure compensation pressure stage is operated in series with the medium pressure cylinder.

[0020] Furthermore, the high load mode is 70% or more of the rated load mode.

[0021] Furthermore, the low load mode is 10% to 70% of the rated load mode.

[0022] Compared with the prior art, the present invention has at least the following advantageous effects:

[0023] The operating load mode of the steam turbine unit is classified. In high-load mode, the normal high-pressure cylinder and medium-pressure cylinder are put into operation, and the high-pressure compensating pressure stage and / or the medium-pressure compensating pressure stage are idled or stopped, reducing the flow area and avoiding a significant drop in main steam pressure during slip-pressure operation of the steam turbine unit. In low-load mode, the high-pressure compensating pressure stage is operated in series with the high-pressure cylinder, and / or the medium-pressure compensating pressure stage is operated in series with the medium-pressure cylinder. In the flow system, connecting the pressure stages in series increases the work share and maintains high unit operating pressure through pressure transmission. The flow state of the turbine unit is dynamically reconfigured based on the operating load mode, avoiding the problem of a sudden drop in energy efficiency due to a drop in main reheat steam operating pressure when the steam turbine unit is in medium- or low-load mode, and improving the adaptability of the steam turbine unit's operating conditions.

[0024] The present invention will now be described in more detail with reference to the drawings and specific embodiments. [Brief explanation of the drawings]

[0025] The present invention will be further described with reference to the drawings, but the embodiments in the drawings do not constitute any limitations on the present invention, and those skilled in the art can obtain other drawings based on the following drawings without paying creative labor.

[0026] [Figure 1] 1 is a structural schematic diagram of a dynamically reconfigured steam turbine power generating unit provided in the present embodiment 1.

[0027] [Figure 2] 1 is a structural schematic diagram of a dynamically reconfigured steam turbine power generating unit provided in this second embodiment.

[0028] [Figure 3] 1 is a structural schematic diagram of a dynamically reconfigured steam turbine power generating unit provided in the third embodiment.

[0029] [Figure 4]1 is a structural schematic diagram of a dynamically reconfigured steam turbine power generating unit provided in Example 4.

[0030] [Figure 5] 1 is a schematic diagram of standard coal consumption in full load mode for a 330MW conventional thermal power generation unit.

[0031] [Figure 6] 1 is a schematic diagram of the regulating stage back pressure and "constant-smooth-constant" main steam pressure change in a 330MW normal thermal power generation unit in full load mode.

[0032] [Figure 7] 10 is a schematic diagram showing how the main steam pressure changes depending on the load when a dynamically reconfigured steam turbine power generation unit and a steam turbine power generation unit in a normal operation mode are used in Example 9.

[0033] [Figure 8] 10 is a schematic diagram of standard coal consumption in full load mode using a dynamically reconfigured steam turbine power generating unit and a steam turbine power generating unit in a normal operation mode in Example 9. DETAILED DESCRIPTION OF THE INVENTION

[0034] The following clearly and completely describes the technical solutions of the present invention with the aid of drawings, but it is clear that the described embodiments are only some of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present invention.

[0035] In describing the present invention, the orientations or positional relationships indicated by terms such as "center," "top," "bottom," "left," "right," "vertical," "horizontal," "inside," and "outside" are based on the orientations or positional relationships shown in the drawings and are intended solely to facilitate and simplify the description of the present invention, and do not indicate or imply that the devices or elements referred to must be configured or operated in a particular orientation, and therefore should not be understood as limitations of the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not understood to indicate or imply relative importance.

[0036] In the description of the present invention, when a specific device is located between a first device and a second device, an intermediate device may or may not exist between the specific device and the first or second device. When describing the case where another device is connected to a specific device, the specific device may be directly connected to the other device without an intermediate device, or may have an intermediate device without being directly connected to the other device.

[0037] Techniques, methods and devices known to those skilled in the art may not be discussed in detail, but where appropriate, said techniques, methods and devices should be considered part of the specification. Example 1:

[0038] Referring to FIG. 1 , this embodiment 1 provides a dynamically reconfigured steam turbine power generating unit, which includes a boiler 12, a first rotating shaft 1, a high-pressure cylinder 3, and an intermediate-pressure cylinder 4, in which the main steam outlet end of the boiler 12 is connected to the steam inlet end piping of the high-pressure cylinder 3 by a main steam pipe, and the main steam pipe is provided with a main valve 13, the exhaust outlet end of the high-pressure cylinder 3 is connected to the reheat steam inlet end piping of the boiler 12 by a cold reheat steam pipe, and the reheat steam outlet end of the boiler 12 is connected to the steam inlet end piping of the intermediate-pressure cylinder 4 by the reheat steam pipe, and the reheat steam pipe is provided with a fourth valve 17, and the high-pressure cylinder 3 and the intermediate-pressure cylinder 4 are sequentially arranged along the central axis direction of the first rotating shaft 1.

[0039] The dynamically reconfigured steam turbine power generation unit further includes a second rotating shaft 2, a high-pressure compensating pressure stage 7, and an energy converter 9. The high-pressure compensating pressure stage 7 and the energy converter 9 are sequentially arranged along the central axis of the second rotating shaft 2. A first valve 14 is provided between the main valve 13 and the high-pressure cylinder 3. A second valve 15 is provided between the main valve 13 and the high-pressure compensating pressure stage 7. The exhaust outlet end of the high-pressure compensating pressure stage 7 is connected to the steam outlet end piping of the first valve 14 by a third valve 16, and then to the steam inlet end piping of the high-pressure cylinder 3. This corresponds to one high-pressure compensating pressure stage 7 being connected in parallel to both the inlet and outlet ends of the first valve 14. When the second valve 15 and the third valve 16 at both ends of the high-pressure compensating pressure stage 7 are closed and the first valve 14 is opened, the main steam passes through the main valve 13 and the first valve 14 sequentially and enters the steam inlet end of the high-pressure cylinder 3. This method is suitable for operation in high load mode. When the second valve 15 and the third valve 16 at both ends of the high pressure compensating pressure stage 7 are opened and the first valve 14 is closed, the main steam passes through the main valve 13, the second valve 15, the high pressure compensating pressure stage 7, and the third valve 16 in sequence, and then enters the steam inlet end of the high pressure cylinder 3, which is equivalent to operating the high pressure compensating pressure stage 7 in series with the high pressure cylinder 3. This method is suitable for operation in low load mode.

[0040] As described above, the steam turbine unit in this embodiment 1 has two work units in the high-pressure section, namely the high-pressure cylinder 3 and the high-pressure compensation pressure stage 7, which can be switched to different connection states according to different load modes, thereby realizing dynamic reconfiguration of the steam turbine unit. Example 2:

[0041] Referring to FIG. 2 , the second embodiment provides a dynamically reconfigured steam turbine power generating unit, which includes a boiler 12, a first rotating shaft 1, a high-pressure cylinder 3, and an intermediate-pressure cylinder 4, in which the main steam outlet end of the boiler 12 is connected to the steam inlet end piping of the high-pressure cylinder 3 by a main steam pipe, and the main steam pipe is provided with a main valve 13, the exhaust outlet end of the high-pressure cylinder 3 is connected to the reheat steam inlet end piping of the boiler 12 by a cold reheat steam pipe, and the reheat steam outlet end of the boiler 12 is connected to the steam inlet end piping of the intermediate-pressure cylinder 4 by the reheat steam pipe, and the reheat steam pipe is provided with a fourth valve 17, and the high-pressure cylinder 3 and the intermediate-pressure cylinder 4 are sequentially arranged along the central axis of the first rotating shaft 1.

[0042] The dynamically reconfigured steam turbine power generation unit further includes a second rotating shaft 2, a medium-pressure compensating pressure stage 8, and an energy converter 9. The medium-pressure compensating pressure stage 8 and the energy converter 9 are sequentially arranged along the central axis of the second rotating shaft 2. The steam inlet end of the medium-pressure compensating pressure stage 8 is connected to the steam inlet pipe of the fourth valve 17 via a fifth valve 18. The exhaust outlet end of the medium-pressure compensating pressure stage 8 is connected to the steam outlet pipe of the fourth valve 17 via a sixth valve 19, and then to the steam inlet pipe of the medium-pressure cylinder 4. This corresponds to one medium-pressure compensating pressure stage 8 being connected in parallel to both the inlet and outlet ends of the fourth valve 17. When the fifth valve 18 and the sixth valve 19 at both ends of the medium-pressure compensating pressure stage 8 are closed and the fourth valve 17 is opened, reheated steam passes through the fourth valve 17 sequentially and enters the steam inlet end of the medium-pressure cylinder 4. This method is suitable for operation in high load mode. When the fifth valve 18 and the sixth valve 19 at both ends of the medium pressure compensating pressure stage 8 are opened and the fourth valve 17 is closed, the reheated steam passes through the fifth valve 18, the medium pressure compensating pressure stage 8, and the sixth valve 19 in sequence, and then enters the steam inlet end of the high / medium pressure cylinder 4. This is equivalent to operating the medium pressure compensating pressure stage 8 in series with the medium pressure cylinder 4, and this method is suitable for operation in low load mode.

[0043] As described above, the steam turbine unit in this embodiment 2 has two work units in the medium pressure section, namely the medium pressure cylinder 4 and the medium pressure compensation pressure stage 8, which can be switched to different connection states according to different load modes, thereby realizing dynamic reconfiguration of the steam turbine unit. Example 3:

[0044] Referring to FIG. 3 , the third embodiment provides a dynamically reconfigured steam turbine power generating unit, which includes a boiler 12, a first rotating shaft 1, a high-pressure cylinder 3, and an intermediate-pressure cylinder 4, in which the main steam outlet end of the boiler 12 is connected to the steam inlet end piping of the high-pressure cylinder 3 by a main steam pipe, and the main steam pipe is provided with a main valve 13, the exhaust outlet end of the high-pressure cylinder 3 is connected to the reheat steam inlet end piping of the boiler 12 by a cold reheat steam pipe, and the reheat steam outlet end of the boiler 12 is connected to the steam inlet end piping of the intermediate-pressure cylinder 4 by the reheat steam pipe, and the reheat steam pipe is provided with a fourth valve 17, and the high-pressure cylinder 3 and the intermediate-pressure cylinder 4 are sequentially arranged along the central axis of the first rotating shaft 1.

[0045] The dynamically reconfigured steam turbine power generation unit further includes a second rotating shaft 2, a high-pressure compensating pressure stage 7, an intermediate-pressure compensating pressure stage 8, and an energy conversion device 9, which are sequentially arranged along the central axis of the second rotating shaft 2. A first valve 14 is provided between the main valve 13 and the high-pressure cylinder 3, and a second valve 15 is provided between the main valve 13 and the high-pressure compensating pressure stage 7. The exhaust outlet end of the high-pressure compensating pressure stage 7 is connected to the steam outlet end piping of the first valve 14 by a third valve 16, and then to the steam inlet end piping of the high-pressure cylinder 3. The steam inlet end of the intermediate-pressure compensating pressure stage 8 is connected to the steam inlet end piping of the fourth valve 17 by a fifth valve 18. The exhaust outlet end of the intermediate-pressure compensating pressure stage 8 is connected to the steam outlet end piping of the fourth valve 17 by a sixth valve 19, and then to the steam inlet end piping of the intermediate-pressure cylinder 4.

[0046] This embodiment 3 corresponds to a combination of the embodiment 1 and the embodiment 2, and a high-pressure compensation pressure stage 7 is added to the high-pressure section, and an intermediate-pressure compensation pressure stage 8 is added to the intermediate-pressure section.

[0047] One high-pressure compensating pressure stage 7 is connected in parallel to both ends of the inlet and outlet of the first valve 14, and one intermediate-pressure compensating pressure stage 8 is connected in parallel to both ends of the inlet and outlet of the fourth valve 17. When operating in high-load mode, the second and third valves 15 and 16 on both ends of the high-pressure compensating pressure stage 7 are closed and the first valve 14 is opened, so that main steam passes through the main valve 13 and the first valve 14 in sequence and enters the steam inlet end of the high-pressure cylinder 3. In addition, the fifth and sixth valves 18 and 19 on both ends of the intermediate-pressure compensating pressure stage 8 are closed and the fourth valve 17 is opened, so that reheat steam passes through the fourth valve 17 in sequence and enters the steam inlet end of the intermediate-pressure cylinder 4. When operating in low load mode, the second valve 15 and the third valve 16 at both ends of the high pressure compensating pressure stage 7 are opened, the first valve 14 is closed, and the main steam passes through the main valve 13, the second valve 15, the high pressure compensating pressure stage 7, the third valve 16 in sequence, and then enters the steam inlet end of the high pressure cylinder 3, which corresponds to operating the high pressure compensating pressure stage 7 in series with the high pressure cylinder 3. Also, the fifth valve 18 and the sixth valve 19 at both ends of the intermediate pressure compensating pressure stage 8 are opened, and the fourth valve 17 is closed, and the reheat steam passes through the fifth valve 18, the intermediate pressure compensating pressure stage 8, the sixth valve 19 in sequence, and then enters the steam inlet end of the high and intermediate pressure cylinder 4, which corresponds to operating the intermediate pressure compensating pressure stage 8 in series with the intermediate pressure cylinder 4. Example 4

[0048] 4, in this fourth embodiment, based on the first or third embodiment, a seventh valve 20 is added. More specifically, the exhaust outlet end of the high pressure compensating pressure stage 7 is connected to the reheat steam inlet end piping of the boiler 12 by the seventh valve 20. In full load mode, the first valve 14, the second valve 15, and the seventh valve 20 are opened, and the third valve 16 is closed, so that the high pressure compensating pressure stage 7 is connected in parallel to the high pressure cylinder 3. The main steam from the boiler 12 is divided into two parts, which respectively enter the high pressure compensating pressure stage 7 and the high pressure cylinder 3. The outlet steams of the high pressure compensating pressure stage 7 and the high pressure cylinder 3 then enter the boiler 12 together for reheating, thereby further improving the work capacity of the steam turbine unit in full load mode. Note that in full load mode, the seventh valve 20 is opened and the third valve 16 is closed to realize parallel operation. In the remaining high load mode and low load mode, the seventh valve 20 is always closed.

[0049] Furthermore, as a further improvement over Examples 1 to 3, a high-pressure cylinder 3, a medium-pressure cylinder 4, a low-pressure cylinder 5, and a generator 6 are arranged in this order along the central axis of the first rotating shaft 1, a condenser 10 is connected to the exhaust outlet end of the low-pressure cylinder 5, and a condensed water outlet of the condenser 10 is connected to a condensed water pump 21, a low-pressure heater 22, a deoxygenator 23, a feed water pump 11, a high-pressure heater 24, and a feed water inlet of a boiler 12 in this order via pipes, thereby forming a circulation system.

[0050] In some embodiments, the load factor at the first state reconfiguration point of the steam turbine power generation unit is n%, the flow area of ​​the high pressure compensation pressure stage 7 is 0.4n% to 1.5n% of the flow area of ​​the high pressure cylinder 3, the load factor at the second state reconfiguration point of the steam turbine power generation unit is m%, and the flow area of ​​the intermediate pressure compensation pressure stage 8 is 0.4m% to 1.5m% of the flow area of ​​the intermediate pressure cylinder 4.

[0051] The values ​​of n and m may be the same or different, and the range of values ​​is 30 to 70%, and the first state reconfiguration point determines at what load rate the high-pressure compensating pressure stage 7 is activated and operated in series with the high-pressure cylinder 3, and the second state reconfiguration point determines at what load rate the intermediate-pressure compensating pressure stage 8 is activated and operated in series with the intermediate-pressure cylinder 4. At a load rate of 30 to 70%, the operating pressure of the steam turbine unit drops significantly, so in this load range, it is necessary to connect the high-pressure compensating pressure stage 7 and / or the intermediate-pressure compensating pressure stage 8 in series to increase the operating pressure. Example 5:

[0052] In this embodiment, the first valve 14 is opened, and the second valve 15 and the third valve 16 are closed. The high pressure compensating pressure stage 7 is idled or stopped according to the load. The idle operation is also a thermal reserve. The flow structure between the high pressure compensating pressure stage 7 and the high pressure cylinder 3 is closed. The main steam is sent from the outlet main steam pipe of the boiler 12 directly to the high pressure cylinder 3 to expand and perform work. The low pressure steam is discharged from the exhaust outlet end of the high pressure cylinder 3 and sent to the reheat steam inlet end of the boiler 12. This reduces the flow area of ​​the high pressure section and prevents a significant drop in the main steam pressure during sliding operation in the high load mode of the unit.

[0053] In the low load mode, the second valve 15 and the third valve 16 are opened, and the first valve 14 is closed, so that the high pressure compensating pressure stage 7 is operated in series with the high pressure cylinder 3. The main steam is sent from the outlet main steam pipe of the boiler 12 to the high pressure compensating pressure stage 7 to expand and perform work. The high pressure compensating pressure stage 7 drives the energy conversion device 9 via the second rotating shaft 2. After performing work, the steam is discharged from the exhaust outlet end of the high pressure compensating pressure stage 7 and flows to the steam inlet end of the high pressure cylinder 3 to expand and continue to perform work. Then, the low pressure steam is discharged from the exhaust outlet end of the high pressure cylinder 3 and sent to the reheat steam inlet end of the boiler 12. By operating the high pressure compensating pressure stage 7 and the high pressure cylinder 3 in series, the work output is increased and a high unit operating pressure is maintained through pressure transmission. Example 6:

[0054] In the sixth embodiment, which is applied to the dynamically reconfigured steam turbine power generating unit of the second or third embodiment, the dynamic reconfiguration of the steam turbine power generating unit is performed in a high-load mode and a low-load mode. In the high-load mode, the fourth valve 17 is opened, and the fifth and sixth valves 18 and 19 are closed. The intermediate-pressure compensating pressure stage 8 is idled or stopped according to the load. The idle mode is also a thermal reserve mode. The flow structure between the intermediate-pressure compensating pressure stage 8 and the intermediate-pressure cylinder 4 is closed. The reheated steam is sent from the reheated steam outlet end of the boiler 12 through a pipe directly to the intermediate-pressure cylinder 4 to expand and perform work. The low-pressure steam is discharged from the exhaust outlet end of the intermediate-pressure cylinder 4 and sent to the steam inlet end of the low-pressure cylinder 5. This reduces the flow area of ​​the intermediate-pressure section and improves the main steam pressure during the sliding operation of the unit.

[0055] In the low load mode, the fifth valve 18 and the sixth valve 19 are opened, and the fourth valve 17 is closed, so that the medium-pressure compensating pressure stage 8 is operated in series with the medium-pressure cylinder 4. The reheated steam is discharged from the reheated steam outlet end of the boiler 12 and sent to the medium-pressure compensating pressure stage 8 through the pipe to expand and perform work. The medium-pressure compensating pressure stage 8 drives the energy conversion device 9 through the second rotating shaft 2. After performing work, the steam is discharged from the exhaust port of the medium-pressure compensating pressure stage 8 and flows to the inlet port of the medium-pressure cylinder 4 to expand and continue to perform work. Then, the low-pressure steam is discharged from the exhaust outlet end of the medium-pressure cylinder 4 and sent to the low-pressure cylinder 5. By operating the medium-pressure compensating pressure stage 8 and the medium-pressure cylinder 4 in series, the work output is increased and a high unit operating pressure is maintained through pressure transmission. Example 7

[0056] This embodiment 7 is used in the dynamically reconfigured steam turbine power generating unit in the above embodiment 3. First, it distinguishes between a high load mode and a low load mode. In the high load mode, the first valve 14 and the fourth valve 17 are opened, and the second valve 15, the third valve 16, the fifth valve 18, and the sixth valve 19 are closed. The high pressure compensating pressure stage 7 and the intermediate pressure compensating pressure stage 8 are idled or stopped. The flow structure between the high pressure compensating pressure stage 7 and the high pressure cylinder 3 is closed, and the flow structure between the intermediate pressure compensating pressure stage 8 and the intermediate pressure cylinder 4 is closed. The main steam is sent directly from the boiler 12 outlet main steam pipe to the high pressure cylinder 3, where it expands and performs work. The method for operating a dynamically reconfigured steam turbine power generating unit improves the main steam pressure during sliding pressure operation by reducing the flow areas of the high-pressure and medium-pressure sections, thereby reducing the flow areas of the high-pressure and medium-pressure sections and avoiding a significant drop in the main steam pressure during sliding pressure operation in a unit high-load mode.

[0057] In the low load mode, the second valve 15, the third valve 16, the fifth valve 18, and the sixth valve 19 are open, the first valve 14 and the fourth valve 17 are closed, the high pressure compensating pressure stage 7 is operated in series with the high pressure cylinder 3, and the medium pressure compensating pressure stage 8 is operated in series with the medium pressure cylinder 4.

[0058] The main steam is sent from the boiler 12 outlet main steam pipe to the high pressure compensating pressure stage 7, where it expands and does work. The high pressure compensating pressure stage 7 drives the energy conversion device 9 via the second rotary shaft 2, and after doing work, the steam is discharged from the exhaust outlet end of the high pressure compensating pressure stage 7 and flows to the steam inlet end of the high pressure cylinder 3, where it expands and continues to do work. Then, the low pressure steam is discharged from the exhaust outlet end of the high pressure cylinder 3 and sent to the reheat steam inlet end of the boiler 12. The reheat steam is discharged from the reheat steam outlet end of the boiler 12 and sent to the medium pressure compensating pressure stage 8 via the pipe, where it expands and does work. Then, the medium pressure compensating pressure stage 8 drives the energy conversion device 9 via the second rotating shaft 2, and after doing work, the steam is discharged from the exhaust port of the medium pressure compensating pressure stage 8 and flows to the inlet port of the medium pressure cylinder 4, where it expands and continues to do work, and then the low pressure steam is discharged from the exhaust outlet end of the medium pressure cylinder 4 and sent to the low pressure cylinder 5, so that the high pressure compensating pressure stage 7 operates in series with the high pressure cylinder 3, and the medium pressure compensating pressure stage 8 operates in series with the medium pressure cylinder 4, thereby increasing the work output and maintaining a high unit operating pressure through pressure transmission.

[0059] In the above embodiment, in the low load mode, the operation effect of the unit is equivalent to increasing the steam work portion, and the operation pressure of the unit in this embodiment is effectively improved compared to the normal unit, so that the unit circulation efficiency and power generation energy efficiency are significantly improved. In some embodiments, the high load mode is 70% or more, preferably 70-90%, of the rated load mode, and the low load mode is 10-70% of the rated load mode. Example 8:

[0060] In the eighth embodiment, used in the dynamically reconfigured steam turbine power generating unit in the fourth embodiment, in the 90-100% full load mode, the high-pressure compensation pressure stage 7 is operated in parallel with the high-pressure cylinder 3, that is, the first valve 14, the second valve 15, and the seventh valve 20 are opened, and the third valve 16 is closed. Example 9:

[0061] Taking a 330MW thermal power unit as an example, Figure 5 shows the standard coal consumption of the 330MW conventional thermal power unit in full load mode, and Figure 6 shows a schematic diagram of the changes in the regulating stage back pressure and the "constant-smooth-constant" main steam pressure of the 330MW conventional thermal power unit in full load mode. In Example 9, using the dynamically reconfigured steam turbine / generator technology of the present invention, the steam turbine / generator flow structure is reconfigured and adjusted to maintain the main steam pressure near the maximum allowable main steam pressure. As shown in Figure 7, comparing the main steam pressure of the dynamically reconfigured steam turbine / generator and the steam turbine / generator in normal operation mode, while the main steam pressure of the conventional power unit drops more quickly with load reduction, the dynamically reconfigured steam turbine / generator in Example 9 maintains the main steam pressure at a high level, effectively improving the unit's power generation energy efficiency. The standard coal consumption is reduced by an average of 12g / kWh, and the standard coal consumption in full load mode is shown in Figure 8.

[0062] Compared with the prior art, the above embodiment provides a dynamically reconfigured steam turbine power generation unit and operating method, which distinguishes between the operating load modes of the steam turbine unit. In high load mode, the normal high pressure cylinder 3 and medium pressure cylinder 4 are put into operation, and the high pressure compensating pressure stage 7 and / or the medium pressure compensating pressure stage 8 are idled or stopped to reduce the flow area and avoid a significant drop in main steam pressure during slip pressure operation of the steam turbine unit. In low load mode, the high pressure compensating pressure stage 7 is operated in series with the high pressure cylinder 3 and / or the medium pressure compensating pressure stage 8 is operated in series with the medium pressure cylinder 4. Through series operation, work is increased and pressure transmission is maintained at a high unit operating pressure. This prevents a sudden drop in energy efficiency due to a drop in main steam operating pressure during peak and low load modes of the steam turbine unit according to the operating load mode and the connection status of the dynamically reconfigured steam turbine unit, thereby improving the mode adaptability of the steam turbine unit.

[0063] The above embodiments are merely preferred embodiments of the present invention, which do not limit the scope of protection of the present invention, and any insubstantial changes and substitutions made by those skilled in the art based on the present invention also fall within the scope of protection claimed by the present invention. [Explanation of symbols]

[0064] 1 First rotating shaft, 2 Second rotating shaft, 3 High-pressure cylinder, 4 Medium-pressure cylinder, 5 Low-pressure cylinder, 6 Generator, 7 High-pressure compensating pressure stage, 8 Medium-pressure compensating pressure stage, 9 Energy conversion device, 10 Condenser, 11 Feed pump, 12 Boiler, 13 Main valve, 14 First valve, 15 Second valve, 16 Third valve, 17 Fourth valve, 18 Fifth valve, 19 Sixth valve, 20 Seventh valve, 21 Condensate pump, 22 Low-pressure heater, 23 Deoxygenator, 24 High-pressure heater.

Claims

1. 1. A dynamically reconfigured steam turbine power generation unit, comprising: a first rotary shaft, a high-pressure cylinder, and an intermediate-pressure cylinder, wherein a main steam outlet end of the boiler is connected to a steam inlet end piping of the high-pressure cylinder by a main steam pipe, the main steam pipe being provided with a main valve; an exhaust outlet end of the high-pressure cylinder is connected to a reheat steam inlet end piping of the boiler by a cold reheat steam pipe; a reheat steam outlet end of the boiler is connected to a steam inlet end piping of the intermediate-pressure cylinder by a reheat steam pipe, the reheat steam pipe being provided with a fourth valve; and the high-pressure cylinder and the intermediate-pressure cylinder are sequentially arranged along a central axis of the first rotary shaft, the steam turbine power generating unit further includes a second rotating shaft, a high-pressure compensating pressure stage, and an energy conversion device, the high-pressure compensating pressure stage and the energy conversion device being sequentially arranged along the central axial direction of the second rotating shaft, a first valve being provided between the main valve and the high-pressure cylinder, and a second valve being provided between the main valve and the high-pressure compensating pressure stage, an exhaust outlet end of the high-pressure compensating pressure stage being connected to a steam outlet end piping of the first valve by a third valve, and then further connected to a steam inlet end piping of the high-pressure cylinder, the load factor of the first state reconfiguration point of the steam turbine power generating unit being n%, the flow area of ​​the high-pressure compensating pressure stage being 0.4n% to 1.5n% of the flow area of ​​the high-pressure cylinder, and the load factor n of the first state reconfiguration point being 30 to 70%. A dynamically reconfigured steam turbine power generating unit comprising:

2. 1. A dynamically reconfigured steam turbine power generation unit, comprising: a first rotary shaft, a high-pressure cylinder, and an intermediate-pressure cylinder, wherein a main steam outlet end of the boiler is connected to a steam inlet end piping of the high-pressure cylinder by a main steam pipe, the main steam pipe being provided with a main valve; an exhaust outlet end of the high-pressure cylinder is connected to a reheat steam inlet end piping of the boiler by a cold reheat steam pipe; a reheat steam outlet end of the boiler is connected to a steam inlet end piping of the intermediate-pressure cylinder by a reheat steam pipe, the reheat steam pipe being provided with a fourth valve; and the high-pressure cylinder and the intermediate-pressure cylinder are sequentially arranged along a central axis of the first rotary shaft, the steam turbine power generating unit further includes a second rotating shaft, an intermediate pressure compensating pressure stage, and an energy conversion device, the intermediate pressure compensating pressure stage and the energy conversion device being sequentially arranged along the central axis of the second rotating shaft, the steam inlet end of the intermediate pressure compensating pressure stage being connected to the steam inlet end piping of the fourth valve by a fifth valve, and the exhaust outlet end of the intermediate pressure compensating pressure stage being connected to the steam outlet end piping of the fourth valve by a sixth valve, and then further connected to the steam inlet end piping of the intermediate pressure cylinder, the load factor of the second state reconfiguration point of the steam turbine power generating unit being m%, the flow area of ​​the intermediate pressure compensating pressure stage being 0.4m% to 1.5m% of the flow area of ​​the intermediate pressure cylinder, and the load factor m of the second state reconfiguration point being 30 to 70%. A dynamically reconfigured steam turbine power generating unit comprising:

3. 1. A dynamically reconfigured steam turbine power generation unit, comprising: a first rotary shaft, a high-pressure cylinder, and an intermediate-pressure cylinder, wherein a main steam outlet end of the boiler is connected to a steam inlet end piping of the high-pressure cylinder by a main steam pipe, the main steam pipe being provided with a main valve; an exhaust outlet end of the high-pressure cylinder is connected to a reheat steam inlet end piping of the boiler by a cold reheat steam pipe; a reheat steam outlet end of the boiler is connected to a steam inlet end piping of the intermediate-pressure cylinder by a reheat steam pipe, the reheat steam pipe being provided with a fourth valve; and the high-pressure cylinder and the intermediate-pressure cylinder are sequentially arranged along a central axis of the first rotary shaft, The system further includes a second rotary shaft, a high-pressure compensating pressure stage, an intermediate-pressure compensating pressure stage, and an energy conversion device, the high-pressure compensating pressure stage, the intermediate-pressure compensating pressure stage, and the energy conversion device being sequentially arranged along the central axis of the second rotary shaft, a first valve being provided between the main valve and the high-pressure cylinder, and a second valve being provided between the main valve and the high-pressure compensating pressure stage, and an exhaust outlet end of the high-pressure compensating pressure stage being connected to a steam outlet end piping of the first valve by a third valve, and then further connected to a steam inlet end piping of the high-pressure cylinder. a steam inlet end of the intermediate-pressure compensating pressure stage is connected to the steam inlet end piping of the fourth valve by a fifth valve, and an exhaust outlet end of the intermediate-pressure compensating pressure stage is connected to the steam outlet end piping of the fourth valve by a sixth valve, and then connected to the steam inlet end piping of the intermediate-pressure cylinder; a load factor of a first state reconfiguration point of the steam turbine power generating unit is n%, a flow area of ​​the high-pressure compensating pressure stage is 0.4n% to 1.5n% of a flow area of ​​the high-pressure cylinder, and the load factor n of the first state reconfiguration point is 30 to 70%. A dynamically reconfigured steam turbine power generating unit comprising:

4. The load factor at the second state reconfiguration point of the steam turbine power generation unit is m%, the flow area of ​​the intermediate pressure compensation pressure stage is 0.4m% to 1.5m% of the flow area of ​​the intermediate pressure cylinder, and the load factor m at the second state reconfiguration point is 30 to 70%. The dynamically reconfigured steam turbine power unit of claim 3 .

5. A method for using the dynamically reconfigured steam turbine power generation unit according to claim 1 or 3, In a high load mode, the first valve is opened, the second valve and the third valve are closed, and the high pressure compensating pressure stage is idled or stopped; in a low load mode, the second valve and the third valve are opened, and the first valve is closed, so that the high pressure compensating pressure stage operates in series with the high pressure cylinder; The high load mode is 70% or more of the rated load mode, The low load mode is 10% to 70% of the rated load mode. A method for operating a dynamically reconfigured steam turbine power generation unit, comprising:

6. A dynamically reconfigured steam turbine power generation unit according to claim 2 or 3, In a high load mode, the fourth valve is opened, the fifth and sixth valves are closed, and the intermediate pressure compensating pressure stage is idled or stopped; in a low load mode, the fifth and sixth valves are opened and the fourth valve is closed, causing the medium pressure compensating pressure stage to operate in series with the medium pressure cylinder; The high load mode is 70% or more of the rated load mode, The low load mode is 10% to 70% of the rated load mode. A method for operating a dynamically reconfigured steam turbine power generation unit, comprising:

7. 4. The dynamically reconfigured steam turbine power generation unit of claim 3, In the high load mode, the first and fourth valves are opened, the second, third, fifth and sixth valves are closed, and the high pressure compensating pressure stage and the intermediate pressure compensating pressure stage are idled or stopped; in a low load mode, the second valve, the third valve, the fifth valve, and the sixth valve are opened, and the first valve and the fourth valve are closed, causing the high pressure compensation pressure stage to operate in series with the high pressure cylinder, and causing the medium pressure compensation pressure stage to operate in series with the medium pressure cylinder; The high load mode is 70% or more of the rated load mode, The low load mode is 10% to 70% of the rated load mode. A method for operating a dynamically reconfigured steam turbine power generation unit, comprising:

Images