CN112145241A - Flow characteristic fine setting method for multi-sequence valve control mode of steam turbine set - Google Patents
Flow characteristic fine setting method for multi-sequence valve control mode of steam turbine set Download PDFInfo
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
- F01D17/00—Regulating or controlling by varying flow
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
- F01D17/00—Regulating or controlling by varying flow
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Abstract
A flow characteristic fine setting method of a multi-sequence valve control mode of a steam turbine set is characterized in that complete information of a valve control pre-starting valve and an idle stroke area is obtained by improving a valve control flow characteristic nonlinear characteristic information test method and by means of the automatic control function of a valve control of a unit set; the method comprises the following steps of (1) finishing the standardized setting of flow characteristics and overlapping degree of a multi-sequence valve control mode steam turbine set according to a given valve sequence value mapping principle; developing a field verification test for the standardized setting of the overlap steam distribution function; based on the refined steam distribution reference curve of the overlapping degree and the steam inlet flow local deviation standard exceeding information obtained by the test, the actual flow of the overlapping area of the throttle valve does not need to be checked, and the refined adjusting steam distribution function of the overlapping degree in a multi-step sequence valve control mode is directly obtained. The invention realizes that the deviation of the steam inlet flow control is less than or equal to 0.3-0.5%, further improves the steam inlet flow regulation precision of the steam turbine set, is helpful to eliminate the power oscillation of the steam turbine set caused by slight abnormality of the flow characteristic and supports the economic operation of the valve point sliding pressure of the steam turbine set in a multi-step valve control mode.
Description
Technical Field
The invention relates to a fine setting method for flow characteristics of a steam turbine set in a multi-step valve control mode, and belongs to the technical field of steam turbine set operation.
Background
Modern steam turbine units have widely adopted a Digital Electro-Hydraulic Control System (DEH) to implement valve management. In daily peak regulation operation, a multi-step valve control mode has great significance for improving the operation economy and flexibility of the turbine set, and is an optimal valve management mode of the steam turbine set. Common multi-sequence valve control modes include a sequence valve mode of a nozzle steam distribution unit (for example, for a nozzle steam distribution unit with 4 steam inlet valves, a three-step sequence valve control mode of "CV 1/2 → CV3 → CV 4" is generally adopted), and a two-step sequence valve control mode of an overload steam-supplementing throttling steam distribution unit (namely, "main valve-steam-supplementing valve").
The flow characteristic of the steam turbine set refers to the numerical value corresponding relation between the actual flow and the valve position of the valve under the established steam distribution structure and valve sequence mode when the steam turbine set runs in a variable load and constant parameter mode. The linearization of the flow characteristic of the regulating valve of the steam turbine set is the basis and guarantee for carrying out the work of modeling of a speed regulating system, excavating valve point sliding pressure bonus, optimizing the coordination performance of a hoist network and main parameters and the like. Whether the steam distribution function can correctly reflect the nonlinear characteristics of the regulating valve or not determines the accuracy of the steam inlet flow control and the power regulation of the steam turbine. In part of the units, the steam distribution function is a group of 'X-Y' broken line functions taking 'total valve position instruction/flow instruction' as an X value and taking 'valve position adjustment instruction' as a Y value.
The actual flow characteristic of the steam turbine set is inconsistent with the reference calibration line (namely, non-linearity) or inconsistent with the total valve position command/flow command (in different control systems, the total valve position command/flow command has the same meaning and different names; hereinafter referred to as the flow command), which is called as flow characteristic abnormality. The inlet flow control offset is numerically equal to the difference between the "actual flow" and the "flow command". The fact that the DEH steam distribution function does not accord with the actual flow characteristics of the steam turbine set is the root cause of flow characteristic malfunction.
According to the steam distribution principle of the established valve sequence numerical value mapping, developing the normalized setting of the flow characteristic and the overlap degree of the regulating valve of the steam turbine set is an effective means for improving the regulation precision of the steam inlet flow and solving the problem of the abnormality of the flow characteristic of the steam turbine set. However, even if the regulation valve flow characteristic and the overlap degree are subjected to normalized setting in operation, the phenomenon of low-frequency oscillation of the unit power at the MW level caused by slight abnormality (deviation of steam inlet flow control is 0.5-5%) of the regulation valve flow characteristic still exists in a partial flow instruction area, and particularly in the regulation valve overlap degree area, the unit in a multi-step sequence valve control mode is difficult to put into valve point sliding pressure economic operation. In order to further improve the regulation precision of the steam inlet flow of the steam turbine set, ensure that the deviation of the steam inlet flow control is less than or equal to 0.3-0.5%, eliminate the problem that the flow characteristic is slightly abnormal to cause the power oscillation of the steam turbine set and support the economic operation of the steam turbine set in a multi-step valve control mode at the valve point sliding pressure, the steam distribution function needs to be further refined and set on the basis of the normalized setting of the valve regulation flow characteristic and the overlap degree of the steam turbine set.
Disclosure of Invention
The invention aims to provide a fine setting method for the flow characteristic of a multi-sequence valve control mode of a steam turbine set, which aims to further improve the regulation precision of the steam inlet flow of the steam turbine set, and the control deviation is less than or equal to 0.3%.
Undoubtedly, the problem of slight abnormality of flow characteristics (namely, the deviation of steam inlet flow control is ensured to be less than or equal to 0.3-0.5%) is solved, and higher technical index requirements are provided for the setting quality of the steam distribution function of the steam turbine set. Essentially, the steam distribution function configuration is a concrete implementation means or way for numerically mapping the flow characteristics of the steam turbine. Under a given steam distribution structure and a given valve sequence, parameters of the steam turbine in the variable working condition process of the steam distribution end can be mapped with each other, the theoretical basis of the flow characteristic setting and the steam distribution calculation of the steam turbine set with various structure types is provided, and the theoretical basis is also the only standard for judging whether the steam distribution calculation is reasonable or not. In order to realize the refined setting of the flow characteristic and the overlapping degree of the valve of the steam turbine set in a multi-step valve control mode, the core still strictly follows the steam distribution principle of the numerical value mapping of the established valve sequence, and the foundation lies in obtaining representative complete information of a valve control pre-starting valve and an idle stroke area; meanwhile, the key point is to skillfully avoid the system error caused by the mutual coupling of the flow characteristics of the gates in the overlapping area. The specific analysis is as follows:
1. adjusting nonlinear characteristic information: taking the N600 ultra-supercritical unit manufactured by the eastern turbine plant as an example, the regulating valve is designed as a counter-flow unloading valve. After the pre-opened valve in the main valve core of the regulating valve is opened, steam enters the unloading chamber of the main valve core from the regulating stage of the steam turbine through the steam guide pipe and then through the pre-opened valve port (for balancing the pressure difference between the upper part and the lower part when the main valve core is opened). That is, the turbine inlet flow is not substantially increased when the pre-open valve is opened. According to the factory set diagram, the stroke of the pre-starting valve is 5CM, and the total stroke of the main valve is 50.8 CM; the pre-opened valve occupies 9.8% of the full stroke of the main valve when being fully opened. However, in the past flow characteristic test, a plurality of units show the phenomenon that the percentage of the stroke of the pre-starting valve exceeds 13% and even reaches 21%. The main reason is that the unit is limited by the DEH system function, and in the steam turbine flow characteristic test process, the flow instruction needs to be manually assigned. If the flow instruction is reduced to be near 60% from 100% in the test process, in order to increase the number of test samples, the field manual assignment frequency needs to reach 300-400 times at intervals of 0.1%, so that the working intensity is high, the risk of mis-delivery and non-stop is caused, the manual assignment cannot follow the change of the system state in the nonlinear region of the regulating valve, meanwhile, the manual assignment cannot make the system state continuously and uniformly change, and the representative complete nonlinear characteristic information of the regulating valve is difficult to obtain, so that the false phenomenon that the stroke percentage of the pre-starting valve is far beyond the design value is generated in the previous test.
2. And (3) regulating the normalization and setting of the overlap degree of the regulating valve: the flow characteristics of the valves in the valve position overlapping state are mutually coupled and extremely complicated, so that an ideal solution for setting the overlapping degree of the valves completely following the actual conditions on site does not exist at present. Firstly, setting the allowable increase of the valve position command of the valve to be 10% when the flow command is increased by 1%; when the valve position amplification exceeds 10%, marking as the overlapping initial position of the preamble adjusting valve; then, calculating the actual flow contribution and the flow loss under the condition that the amplitude ratio of the preorder regulating valve is increased according to the 10% valve position along with the increase of the flow instruction according to the actual flow gain curve of a single regulating valve; and finally, calculating the valve position command reaching value of the subsequent regulating valve which grows along with the flow command by the flow missing quantity. The simplified processing method by means of the established valve sequence reverse mapping has the advantages that the overlapped initial valve positions of the preorder valves follow the flow characteristics of single valves, and the defects that the flow gain of each valve is considered in isolation, the mutual coupling is neglected, the steam turbine principle is not met, the site practice is not followed, and the slight deviation of the actual flow and the flow instruction is caused inevitably.
The technical scheme of the invention is that a fine setting method for the flow characteristic of a multi-step sequence valve control mode of a steam turbine set is realized, and the method obtains representative complete information of a valve control pre-starting valve and an idle stroke area by improving a valve control flow characteristic nonlinear characteristic information test method and with the help of the automatic control function of the valve control of the unit set; the method comprises the following steps of (1) finishing the standardized setting of flow characteristics and overlapping degree of a multi-sequence valve control mode steam turbine set according to a given valve sequence value mapping principle; developing a field verification test for the standardized setting of the overlap steam distribution function; based on the refined steam distribution reference curve of the overlapping degree and the steam inlet flow local deviation standard exceeding information obtained by the test, the actual flow of the overlapping area of the throttle valve does not need to be checked, and the refined adjusting steam distribution function of the overlapping degree in a multi-step sequence valve control mode is directly obtained.
The method comprises the following steps:
(1) before the test, the unit quits the automatic AGC (automatic Generation Control) power Generation function and quits the primary frequency modulation function of a CCS (coordinated Control System) system and a DEH system so as to avoid the interference of power grid frequency fluctuation. The load of the unit is increased to 90% of the rated load by an operator, and all the valves are in a fully open state by setting the pressure bias of a CCS system; after the parameters are stable, taking all the adjusting valve fully-opened states and corresponding main steam pressures as test initial working conditions and initial pressures, and completing the test of the zero-overlap flow characteristic of the unit to be implemented in a multi-step valve control mode under the original steam distribution function; by means of the automatic control function of the unit set gate regulating, the method for testing the nonlinear characteristic information of the gate regulating flow characteristic is improved as follows: in the test process, manually and continuously reducing the load instruction of the boiler master control in the CCS system at a certain speed; according to the automatic control mode of the regulating valve of the implementing unit, a CCS (turbine follow) steam turbine tracking mode or an OA (operator automation) control mode of a DEH (digital instrumentation) system can be selected, so that each regulating valve is continuously, slowly and unidirectionally and automatically closed, and representative complete information of a nonlinear area of the flow characteristic of the regulating valve is obtained.
(2) Sequentially calculating actual flow of 'taking all-open working condition parameters of all the valves as per unit values' corresponding to valve position instructions of all the valves according to zero-overlap flow characteristic test data of a multi-step sequence valve control mode under the original steam distribution function; taking the actual flow as an abscissa and the corresponding valve position instructions of the valves as an ordinate, and generating a normalized setting zero-overlap steam distribution curve of a multi-step valve control mode from the minimum valve position of the test to the full-open range of the valves; and selecting a representative valve position state point in a nonlinear region of the valve regulation flow characteristic to obtain a normalized setting zero-overlap steam distribution function in a multi-step sequence valve control mode.
(3) According to the normalized setting zero-overlap steam distribution curve of the multi-step valve control mode, calculating the corresponding valve position amplification of the preorder regulating valve when the flow instruction is amplified by 1%; when the valve position amplification exceeds 10%, marking as the overlapping initial position of the preamble adjusting valve; then setting the preamble adjusting door to increase the linear opening until the door is fully opened.
And calculating the amplification of the actual flow corresponding to different valve position instructions in the opening process of the valve one by taking the actual flow when the valve is fully closed as a reference according to the valve position instructions and the corresponding actual flow of each valve obtained by the multi-step valve control mode zero-overlap degree test to obtain the actual flow gain curve of a single valve.
Calculating the actual flow contribution and the flow loss under the condition that the preorder regulating valve increases along with the flow instruction according to the actual flow gain curve of the preorder regulating valve according to the 10 percent valve position amplification proportion; then, according to the actual flow gain curve of the subsequent regulating gate, a valve position command reaching value of the subsequent regulating gate, which is increased along with the flow command, is reversely mapped by the flow missing quantity so as to make up for the insufficient flow gain generated by delayed opening of the preamble regulating gate; at this point, the normalized setting of the adjusting valve overlapping degree is completed; and further obtaining a normalized setting overlap steam distribution function of a multi-sequence valve control mode.
(4) And (4) repeating the step (1) to finish the flow characteristic test of the unit to be implemented under the normalized setting overlap steam distribution function obtained in the step (3).
(5) According to the test data in the step (4), calculating in sequence to obtain the actual flow corresponding to the valve position instructions of each valve, wherein the actual flow takes the all-open working condition parameters of all the valves as per unit values; and then, taking the actual flow as an abscissa and the corresponding valve position instructions of the valves as an ordinate, so as to generate a refined overlapping steam distribution reference curve of a multi-step sequence valve control mode from the minimum valve position of the test to the full-open range of the valves.
(6) Comparing the flow characteristic test result of the normalized setting overlap steam distribution function obtained in the step (4) with a reference calibration line, and finding out a flow range with the deviation between the actual flow and the flow instruction being more than or equal to 0.3%; according to the local deviation overproof information of the steam inlet flow, the actual flow of the throttle valve overlapping area is not required to be calculated, representative valve position state points of the throttle valve flow characteristic nonlinear area are selected on a refined overlapping degree steam distribution reference curve obtained through the test, and a final refined overlapping degree steam distribution function in a multi-step sequence valve control mode is formed through smooth connection.
The refined setting overlap degree steam distribution function of the multi-step valve control mode is a steam distribution function with overlap degree formed by smooth connecting lines and selecting representative valve position state points in a nonlinear area of the throttle flow characteristic on a refined overlap degree steam distribution reference curve obtained by a test without calculating the actual flow of the throttle overlap area.
The invention has the advantages that the representative complete information of nonlinear regions such as a valve pre-opening valve, an idle stroke and the like can be obtained; meanwhile, the actual flow recorded when the valves are sequentially closed according to a set valve sequence in the flow characteristic test process under the normalized setting overlap steam distribution function is directly regarded as the flow command, and a multi-sequence valve control mode overlap steam distribution curve with completely consistent actual flow and flow command is obtained; the method not only strictly follows the steam distribution principle of the established valve sequence numerical value mapping in the implementation process, and has accurate result, but also keeps the relative valve positions of the preorder regulating valve and the postorder regulating valve in the normalized setting overlapping degree steam distribution function unchanged in the implementation process, so that the overlapping degree of the regulating valves does not need to be re-checked according to the step (3) of the method, and the system error caused by mutual coupling of the flow characteristics of the regulating valves in the overlapping area is avoided. Therefore, the deviation of the steam inlet flow control is less than or equal to 0.3-0.5%, the regulation precision of the steam inlet flow of the steam turbine set is further improved, the power oscillation of the steam turbine set caused by slight abnormality of the flow characteristic is avoided, and the economic operation of the steam turbine set valve point sliding pressure in a multi-step valve control mode is supported.
Drawings
FIG. 1 shows the power low frequency oscillation phenomenon of the test set of this embodiment;
FIG. 2 is the nonlinear characteristic information of the valve adjusting pre-opening valve obtained by the improved testing method according to the embodiment;
FIG. 3 is a multi-step sequence valve control mode overlap steam distribution curve of the test unit in this embodiment;
fig. 4 is a fine tuning of the steam distribution curve (with overlapping degree) of the test unit in this embodiment.
Detailed Description
The specific embodiments of the invention are shown in the attached drawings. The technical solution in the embodiment of the present invention will be clearly and completely described below with reference to fig. 1 to 4 in the embodiment of the present invention.
The unit of the embodiment is an ultra-supercritical 660 MW-grade steam turbine unit, and the sequence of the opening sequence of the gate is GV2/4 (synchronous) → CV3 → CV1 under the mode of a sequence valve. Fig. 1 shows the power low frequency oscillation phenomenon during the operation of the experimental set of this embodiment.
The method for finely setting the flow characteristics of the steam turbine set in the multi-step valve control mode comprises the following steps:
(1) before the test, the unit quits the automatic AGC (automatic Generation Control) power Generation function and quits the primary frequency modulation function of a CCS (coordinated Control System) system and a DEH system so as to avoid the interference of power grid frequency fluctuation. The load of the unit is increased to 90% of the rated load by an operator, and all the valves are in a fully open state by setting the pressure bias of the CCS system. And after the parameters are stable, taking all the adjusting valve fully-opened states and the corresponding main steam pressure as the initial working condition and the initial pressure of the test, and completing the test of the zero-overlap flow characteristic of the unit to be implemented in a multi-step valve control mode under the original steam distribution function. In order to obtain representative complete information of a valve pre-opening valve and an idle stroke area, the method for testing the nonlinear characteristic information of the valve flow characteristic is improved by means of the automatic control function of the unit set valve, and comprises the following steps: in the test process, manually and continuously reducing the load instruction of the boiler master control in the CCS system at a certain speed; according to the automatic control mode of the throttle of the unit, a CCS system tf (turbine follow) steam turbine tracking mode or a DEH system oa (operator automation) control mode can be selected, and each throttle is continuously, slowly and unidirectionally and automatically closed, so as to obtain representative complete information of a nonlinear region of the throttle flow characteristic (see fig. 2).
In the unit test process, a TF mode is skillfully utilized to induce the regulating valve to be slowly and unidirectionally closed at a certain speed, and the flow characteristic information of the pre-opening valve is completely recorded. Fig. 2 clearly shows that the percentage of full open stroke of the pre-opened valve is 8.1%, which is substantially in accordance with the design paper. The previous 20% artefact is due to the severe non-linearity of the flow characteristic of the main spool at small openings.
(2) Sequentially calculating actual flow corresponding to valve position instructions of each valve by taking all valve fully-open working condition parameters as per unit values according to zero-overlap flow characteristic test data of a multi-step valve control mode under the original steam distribution function; then, by taking the actual flow as an abscissa and the corresponding valve position instructions of the valves as an ordinate, a normalized setting zero-overlap steam distribution curve of a multi-step sequence valve control mode from the minimum valve position of the test to the full-open range of the valves can be generated; according to the structural characteristics of the steam distribution configuration of the implementing unit, representative valve position state points of a nonlinear region of the flow characteristic of the regulating valve are selected to obtain a normalized setting zero-overlap steam distribution function of a multi-step sequence valve control mode.
The normalization setting overlap degree steam distribution function of the multi-step sequence valve control mode is a steam distribution function which is used for completing normalization setting of the turnstile overlap degree (namely, a normalization simple processing is carried out according to an actual flow gain curve of a single turnstile in a non-overlap degree state by neglecting mutual coupling between a preamble and a subsequent turnstile steam inlet flow) on the basis of the normalization setting zero overlap degree steam distribution function of the multi-step sequence valve control mode.
(3) Firstly, according to the normalized setting zero-overlap steam distribution curve of the multi-sequence valve control mode obtained in the step (2), calculating the valve position amplification size corresponding to the preamble valve when the flow instruction is amplified by 1%; when the valve position amplification exceeds 10%, marking as the overlapping initial position of the preamble adjusting valve; then setting the preamble adjusting door to increase the linear opening until the door is fully opened.
Secondly, calculating valve position instructions of each valve and corresponding actual flow one by one according to the zero-overlap test data of the multi-step sequence valve control mode in the step (2), and calculating the amplification of the actual flow corresponding to different valve position instructions in the opening process of the valve one by taking the actual flow when each valve is completely closed as a reference to obtain an actual flow gain curve of a single valve; calculating the actual flow contribution and the flow loss under the condition that the preorder regulating valve increases along with the flow instruction according to the actual flow gain curve of the preorder regulating valve according to the 10 percent valve position amplification proportion; and then according to the actual flow gain curve of the subsequent regulating gate, reversely mapping a valve position command reaching value of the subsequent regulating gate increased along with the flow command by the flow missing quantity so as to make up for the insufficient flow gain generated by delayed opening of the preamble regulating gate.
And at this moment, completing the normalized setting of the adjusting valve overlapping degree. Further, a normalized setting overlap steam distribution function of a multi-sequence valve control mode is obtained (see the normalized setting result legend in table 1 and fig. 3).
(4) Repeating the step (1), and completing the test of the flow characteristic of the unit to be implemented under the normalized setting overlap steam distribution function obtained in the step (3);
(5) according to the test data in the step (4), calculating in sequence to obtain the actual flow corresponding to the valve position instructions of each valve, wherein the actual flow takes the all-open working condition parameters of all the valves as per unit values; then, by taking the actual flow as an abscissa and the corresponding valve position instructions of the valves as an ordinate, a refined overlap steam distribution reference curve of a multi-step valve control mode from the minimum valve position of the test to the full-open range of the valves can be generated (see a refined setting reference legend in fig. 3 or fig. 4);
(6) comparing the flow characteristic test result of the normalized setting overlap steam distribution function obtained in the step (4) with a reference calibration line, and finding out a flow range with the deviation between the actual flow and the flow instruction being more than or equal to 0.3% (as can be seen from fig. 4, the flow deviation in two areas exceeds the standard); referring to the information that the local deviation of the steam inflow exceeds the standard, without calculating the actual flow of the overlapping area of the valve, on the refined overlapping steam distribution reference curve obtained by the experiment (for example, the refined setting reference legend in fig. 4 represents the flow characteristics of the valve at the stages of pre-opening valve opening and small opening of the main valve core), representative valve position state points (see the points of (the) ((the)) of the nonlinear area of the valve flow characteristics) are selected, and a final refined setting overlapping steam distribution function in a multi-step valve control mode is formed by smooth connection lines (see table 2).
The method for refining and setting the flow characteristic of the steam turbine set in the multi-step valve control mode is described in detail, a specific example is applied in the embodiment to explain the principle and the implementation mode of the invention, and the description of the embodiment is only used for helping to understand the method and the core idea of the invention. It should be noted that, for those skilled in the art, it is possible to make various improvements and modifications to the present invention without departing from the principle of the present invention, and those improvements and modifications also fall within the scope of the claims of the present invention.
Claims (3)
1. A fine setting method for flow characteristics of a steam turbine set in a multi-step sequence valve control mode is characterized in that the method obtains representative complete information of a valve control pre-starting valve and an idle stroke area by improving a valve control flow characteristic nonlinear characteristic information test method and with the help of an automatic control function of a unit set valve control; the method comprises the following steps of (1) finishing the standardized setting of flow characteristics and overlapping degree of a multi-sequence valve control mode steam turbine set according to a given valve sequence value mapping principle; developing a field verification test for the standardized setting of the overlap steam distribution function; based on the refined steam distribution reference curve of the overlapping degree and the steam inlet flow local deviation standard exceeding information obtained by the test, the actual flow of the overlapping area of the throttle valve does not need to be checked, and the refined adjusting steam distribution function of the overlapping degree in a multi-step sequence valve control mode is directly obtained.
2. The fine setting method for the flow characteristic of the steam turbine set in the multi-step valve control mode is characterized by comprising the following steps of:
(1) before the test, the unit quits the AGC automatic power generation function and quits the primary frequency modulation function of the CCS system and the DEH system, the load of the unit is increased to 90% of the rated load by an operator, and all the valves are in a fully open state by setting the pressure bias of the CCS system; after the parameters are stable, taking all the adjusting valve fully-opened states and corresponding main steam pressures as test initial working conditions and initial pressures, and completing the test of the zero-overlap flow characteristic of the unit to be implemented in a multi-step valve control mode under the original steam distribution function; by means of the automatic control function of the unit set gate regulating, the method for testing the nonlinear characteristic information of the gate regulating flow characteristic is improved as follows: in the test process, manually and continuously reducing the load instruction of the boiler master control in the CCS system at a certain speed; according to the automatic control mode of the throttle of the implementation unit, selecting a TF steam turbine tracking mode of a CCS system or an OA control mode of a DEH system, and enabling each throttle to be continuously, slowly and unidirectionally and automatically closed to obtain representative complete information of a nonlinear region of the throttle flow characteristic;
(2) sequentially calculating actual flow of 'taking all-open working condition parameters of all the valves as per unit values' corresponding to valve position instructions of all the valves according to zero-overlap flow characteristic test data of a multi-step sequence valve control mode under the original steam distribution function; taking the actual flow as an abscissa and the corresponding valve position instructions of the valves as an ordinate, and generating a normalized setting zero-overlap steam distribution curve of a multi-step valve control mode from the minimum valve position of the test to the full-open range of the valves; selecting representative valve position state points in a nonlinear region of the valve regulation flow characteristic to obtain a normalized setting zero-overlap steam distribution function of a multi-step sequence valve control mode;
(3) according to the normalized setting zero-overlap steam distribution curve of the multi-step valve control mode, calculating the corresponding valve position amplification of the preorder regulating valve when the flow instruction is amplified by 1%; when the valve position amplification exceeds 10%, marking as the overlapping initial position of the preamble adjusting valve; then setting a preamble adjusting door to increase the amplitude to open linearly until the door is fully opened;
calculating the amplification of actual flow corresponding to different valve position instructions in the opening process of the valve one by taking the actual flow when the valve is fully closed as a reference according to the valve position instructions and the corresponding actual flow of the valve obtained by the multi-step valve control mode zero-overlap test to obtain an actual flow gain curve of a single valve;
calculating the actual flow contribution and the flow loss under the condition that the preorder regulating valve increases along with the flow instruction according to the actual flow gain curve of the preorder regulating valve according to the 10 percent valve position amplification proportion; then, according to the actual flow gain curve of the subsequent regulating gate, a valve position command reaching value of the subsequent regulating gate, which is increased along with the flow command, is reversely mapped by the flow missing quantity so as to make up for the insufficient flow gain generated by delayed opening of the preamble regulating gate; at this point, the normalized setting of the adjusting valve overlapping degree is completed; further obtaining a normalized setting overlap steam distribution function of a multi-sequence valve control mode;
(4) repeating the step (1), and completing the test of the flow characteristic of the unit to be implemented under the normalized setting overlap steam distribution function obtained in the step (3);
(5) according to the test data in the step (4), calculating in sequence to obtain the actual flow corresponding to the valve position instructions of each valve, wherein the actual flow takes the all-open working condition parameters of all the valves as per unit values; then, taking the actual flow as an abscissa and the corresponding valve position instructions of the valves as an ordinate, namely generating a refined overlapping steam distribution reference curve of a multi-step sequence valve control mode from the minimum valve position of the test to the full-open range of the valves;
(6) comparing the flow characteristic test result of the normalized setting overlap steam distribution function obtained in the step (4) with a reference calibration line, and finding out a flow range with the deviation between the actual flow and the flow instruction being more than or equal to 0.3%; according to the local deviation overproof information of the steam inlet flow, the actual flow of the throttle valve overlapping area is not required to be calculated, representative valve position state points of the throttle valve flow characteristic nonlinear area are selected on a refined overlapping degree steam distribution reference curve obtained through the test, and a final refined overlapping degree steam distribution function in a multi-step sequence valve control mode is formed through smooth connection.
3. The fine setting method for the flow characteristic of the steam turbine set in the multi-step sequence valve control mode according to claim 2, wherein the fine setting overlap degree steam distribution function of the multi-step sequence valve control mode is a steam distribution function with overlap degree formed by smooth connecting lines by selecting representative valve position state points in a nonlinear region of the throttle flow characteristic on a fine overlap degree steam distribution reference curve obtained by a test without calculating actual flow of the throttle overlap region.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113341691A (en) * | 2021-05-20 | 2021-09-03 | 中铝中州铝业有限公司 | Steam turbine DEH system setting method |
| CN114165294A (en) * | 2021-12-06 | 2022-03-11 | 山西荣盛志达科技有限责任公司 | Novel steam turbine valve control method |
| CN114526127A (en) * | 2022-01-07 | 2022-05-24 | 呼伦贝尔安泰热电有限责任公司海拉尔热电厂 | Steam turbine valve flow characteristic test system |
Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4088875A (en) * | 1975-11-04 | 1978-05-09 | Westinghouse Electric Corp. | Optimum sequential valve position indication system for turbine power plant |
| US4178763A (en) * | 1978-03-24 | 1979-12-18 | Westinghouse Electric Corp. | System for minimizing valve throttling losses in a steam turbine power plant |
| US4418285A (en) * | 1972-11-15 | 1983-11-29 | Westinghouse Electric Corp. | System and method for controlling a turbine power plant in the single and sequential valve modes with valve dynamic function generation |
| US4866940A (en) * | 1988-07-25 | 1989-09-19 | Westinghouse Electric Corp. | Computer aided tuning of turbine controls |
| CN104849052A (en) * | 2015-04-29 | 2015-08-19 | 国家电网公司 | Nozzle governing steam turbine flow characteristic test method |
| CN105240058A (en) * | 2015-11-06 | 2016-01-13 | 国网河南省电力公司电力科学研究院 | Steam turbine flow curve identifying and optimizing method based on spray nozzle flow calculation |
| CN106014500A (en) * | 2016-05-31 | 2016-10-12 | 国网江西省电力科学研究院 | Method for identifying and setting degree-of-overlapping of steam admission regulating valves for steam turbine |
| CN109918729A (en) * | 2019-01-31 | 2019-06-21 | 国网江西省电力有限公司电力科学研究院 | A kind of Steam Turbine is hybrid to match vapour Function Synthesis setting method |
| CN110332021A (en) * | 2019-06-11 | 2019-10-15 | 国网江西省电力有限公司电力科学研究院 | A kind of DEH system adjusting valve overlap standardization setting method |
| CN110735668A (en) * | 2019-10-22 | 2020-01-31 | 国网江西省电力有限公司电力科学研究院 | indirect method steam distribution function setting value simplification realization method |
-
2020
- 2020-09-08 CN CN202010932224.1A patent/CN112145241B/en active Active
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4418285A (en) * | 1972-11-15 | 1983-11-29 | Westinghouse Electric Corp. | System and method for controlling a turbine power plant in the single and sequential valve modes with valve dynamic function generation |
| US4088875A (en) * | 1975-11-04 | 1978-05-09 | Westinghouse Electric Corp. | Optimum sequential valve position indication system for turbine power plant |
| US4178763A (en) * | 1978-03-24 | 1979-12-18 | Westinghouse Electric Corp. | System for minimizing valve throttling losses in a steam turbine power plant |
| US4866940A (en) * | 1988-07-25 | 1989-09-19 | Westinghouse Electric Corp. | Computer aided tuning of turbine controls |
| CN104849052A (en) * | 2015-04-29 | 2015-08-19 | 国家电网公司 | Nozzle governing steam turbine flow characteristic test method |
| CN105240058A (en) * | 2015-11-06 | 2016-01-13 | 国网河南省电力公司电力科学研究院 | Steam turbine flow curve identifying and optimizing method based on spray nozzle flow calculation |
| CN106014500A (en) * | 2016-05-31 | 2016-10-12 | 国网江西省电力科学研究院 | Method for identifying and setting degree-of-overlapping of steam admission regulating valves for steam turbine |
| CN109918729A (en) * | 2019-01-31 | 2019-06-21 | 国网江西省电力有限公司电力科学研究院 | A kind of Steam Turbine is hybrid to match vapour Function Synthesis setting method |
| CN110332021A (en) * | 2019-06-11 | 2019-10-15 | 国网江西省电力有限公司电力科学研究院 | A kind of DEH system adjusting valve overlap standardization setting method |
| CN110735668A (en) * | 2019-10-22 | 2020-01-31 | 国网江西省电力有限公司电力科学研究院 | indirect method steam distribution function setting value simplification realization method |
Non-Patent Citations (5)
| Title |
|---|
| 万忠海等: "DEH系统调节阀重叠度辨识及规范化整定方法", 《中国电力》 * |
| 万忠海等: "过载补汽节流配汽机组流量特性及重叠度试验研究", 《汽轮机技术》 * |
| 张志鹏等: "超超临界机组一次调频优化研究", 《山东工业技术》 * |
| 蔡文等: "国产引进型300 MW等级汽轮机组流量特性综合整定试验研究", 《江西电力》 * |
| 赵婷等: "由高调门特性问题引发的汽轮机负荷失控故障诊断", 《汽轮机技术》 * |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113341691A (en) * | 2021-05-20 | 2021-09-03 | 中铝中州铝业有限公司 | Steam turbine DEH system setting method |
| CN113341691B (en) * | 2021-05-20 | 2022-08-12 | 中铝中州铝业有限公司 | Steam turbine DEH system setting method |
| CN114165294A (en) * | 2021-12-06 | 2022-03-11 | 山西荣盛志达科技有限责任公司 | Novel steam turbine valve control method |
| CN114165294B (en) * | 2021-12-06 | 2024-05-17 | 山西荣盛志达科技有限责任公司 | Novel steam turbine valve control method |
| CN114526127A (en) * | 2022-01-07 | 2022-05-24 | 呼伦贝尔安泰热电有限责任公司海拉尔热电厂 | Steam turbine valve flow characteristic test system |
| CN114526127B (en) * | 2022-01-07 | 2024-06-04 | 呼伦贝尔安泰热电有限责任公司海拉尔热电厂 | Turbine valve flow characteristic test system |
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