CN103266923B - Method for obtaining effective data from turbine actuator parameter measured data - Google Patents

Abstract

The present invention introduces a method for obtaining effective data from the measured data of steam turbine actuator parameters, the method comprising the following steps: (1) curve fitting to obtain a smooth data curve; (2) differential processing to obtain differentially processed data v; (3) Threshold value judges the differentially processed data v; (4) Selects valid data segments. By performing curve fitting, differential processing, and threshold judgment sequentially from the actual measurement of the parameters of the steam turbine actuator, the method can accurately and effectively obtain the effective data in the actual measurement data of the steam turbine actuator parameters, thereby improving the parameters of the steam turbine actuator. Measure the efficiency and effect of effective data acquisition work, thereby further improving the efficiency and accuracy of steam turbine actuator parameter identification, which is very beneficial to the stability analysis and calculation of the power grid.

Description

The method of obtaining effective data from the measured data of steam turbine actuator parameters

technical field

The invention belongs to the technical field of steam turbines, in particular to the actual measurement, identification and modeling of the parameters of the steam turbine actuators, in particular to a method for obtaining effective data from the actual measurement data of the parameters of the steam turbine actuators.

Background technique

The actuator is an important link in the steam turbine model. Therefore, the implementation of parameter measurement, identification and modeling for this part of the steam turbine is an essential step to establish an accurate steam turbine model, which is of great significance to the stability analysis and calculation of the power grid. Generally speaking, the actual measurement of the parameters of the actuator of the steam turbine is completed through the step test of the actuator. The effective data for identification that can be obtained by using this method is only the data of the step opening and step closing process of the actuator. A large amount of steady-state data is invalid for identification and needs to be eliminated to improve identification efficiency and accuracy. However, the acquisition of the effective data of the actual measurement of the traditional steam turbine actuator parameters is carried out manually, that is, the required data section is selected by manually observing the graphic curve of the actual measurement data. Due to the large amount of data and the subjectivity of manual observation, it often leads to a large workload and long time-consuming consequences. Even so, the obtained data is still doped with a large amount of invalid data, which seriously affects the efficiency and accuracy of steam turbine actuator parameter identification.

Contents of the invention

The technical problem to be solved by the present invention is to provide a method for obtaining effective data from the measured data of the steam turbine actuator parameters in view of the defects in the prior art. Using this method can accurately and quickly select the effective data needed for parameter identification of steam turbine actuators, eliminate the interference of invalid data on identification, and improve the efficiency and accuracy of parameter identification of steam turbine actuators.

The technical solution of the present invention is that the method for obtaining effective data from the actual measurement data of the steam turbine actuator parameters provided above includes the following steps:

(1) Curve fitting: Due to the influence of many factors such as the actual measurement environment, the quality of the data sampling device, and electromagnetic interference, most of the actual measurement data of the steam turbine actuator parameters are mixed with noise data, so curve fitting is required to obtain a Smooth data curve. Specifically, a least square method is used to perform a conventional fitting operation on the measured data of the steam turbine actuator parameters to obtain a smooth data curve of the steam turbine actuator parameter measured data;

(2), Differential processing: Carry out conventional differential operation to the smooth data curve gained in step (1), obtain the data v after the differential processing of the measured data of the above-mentioned steam turbine actuator parameters, the physical meaning of the data v after the differential processing of the gained is each time point The corresponding actuator action speed;

(3), threshold judgment: in the steady-state operation process before or after the above-mentioned steam turbine actuator step action, the theoretical action speed of this steam turbine actuator is 0%/s, and s represents second in the formula; The theoretical action speed during the jump action process is determined by the inherent characteristics of the steam turbine actuator. Therefore, the steady-state operation process data of the steam turbine actuator and the step operation process data of the steam turbine actuator can be distinguished by setting the action speed threshold of the actuator. Specifically, set the operating speed threshold of the steam turbine actuator as v ₀ , and use the threshold v ₀ to make the following judgments on each differentiated data v obtained in step (2): if v>v ₀ , it belongs to the steam turbine The effective data section of the actuator to open the step action test, record the start and end time of this section as t ₁ , t ₁ ′, where t represents the time; if v<-v ₀ , it belongs to the closing stage of the steam turbine actuator The effective data section of the jumping action test, record the start and end time of this section as t ₂ , t ₂ ′;

(4), select valid data segment: in order to ensure that all valid data is obtained, the value of _t1 or _t2 obtained in step (3) is respectively subtracted by 1 second, and the value of _t1 ' or _t2 ' obtained in step (3) The value of each plus 1 second. In this way, the original measured data in the (t ₁ -1) and (t ₁ '+1) time intervals obtained include all valid data of the steam turbine actuator opening step action test; the obtained (t ₂ -1), The original measured data in the time period (t ₂ ′+1) includes all valid data of the closing step action test of the steam turbine actuator.

The beneficial effect of the present invention is that: the method can accurately and effectively acquire effective data in the measured data of the parameters of the steam turbine actuator by sequentially performing curve fitting, differential processing, and threshold value judgment from the actual measurement of the parameters of the steam turbine actuator. It is precisely because of the ability to accurately and quickly obtain the actual measured effective data of the steam turbine actuator parameters, so that the efficiency and effect of obtaining the actual measured effective data of the steam turbine actuator parameters can be improved, thereby further improving the efficiency and accuracy of the steam turbine actuator parameter identification, It is very beneficial to the stability analysis and calculation of the power grid.

Detailed ways

Example 1:

(1), curve fitting: adopt the least square method, carry out conventional fitting operation to the measured data of steam turbine actuator parameters, obtain the smooth data curve of the measured data of the steam turbine actuator parameters;

(2), Differential processing: Carry out conventional differential operation to the smooth data curve gained in step (1), obtain the data v after differential processing of the measured data of the above-mentioned steam turbine actuator parameters, the physical meaning of the data v after the differential processing of the gained is each time point The corresponding actuator action speed;

(3) Threshold judgment: Assuming that the operating speed threshold of the steam turbine actuator is v ₀ , use the threshold v ₀ to make the following judgment on each differentially processed data v obtained in step (2): v>v ₀ , which belongs to the The steam turbine actuator opens the effective data section of the step action test, and the start and end time of this section are recorded as t ₁ and t ₁ ′;

(4) Select valid data segments: subtract 1 second from the value of t ₁ obtained in step (3), and add 1 second to the value of t ₁ ′ obtained in step (3). The obtained original measured data in the time intervals of (t ₁ -1) and (t ₁ ′+1) include all valid data of the steam turbine actuator opening step action test.

Example 2:

Steps (1)～(2) are with embodiment 1;

(3) Threshold judgment: Assuming that the operating speed threshold of the steam turbine actuator is v ₀ , use the threshold v ₀ to make the following judgment on each differentially processed data v obtained in step (2): v<-v ₀ , which belongs to all Describe the valid data section of the steam turbine actuator closing step action test, record the start and end time of this section as t ₂ , t ₂ ′;

(4) Select valid data segments: subtract 1 second from the value of t ₂ obtained in step (3), and add 1 second to the value of t ₂ ′ obtained in step (3). The obtained original measured data in the time intervals of (t ₂ −1) and (t ₂ ′+1) include all valid data of the closing step action test of the actuator of the steam turbine.

Claims (1)

1. A method for obtaining effective data from steam turbine actuator parameter measured data, the method may further comprise the steps: (1), curve fitting: adopt the least square method, carry out conventional fitting operation to the measured data of steam turbine actuator parameters, obtain the smooth data curve of the measured data of the steam turbine actuator parameters; (2), Differential processing: Carry out conventional differential operation to the smooth data curve gained in step (1), obtain the data v after the differential processing of the measured data of the above-mentioned steam turbine actuator parameters, the physical meaning of the data v after the differential processing of the gained is each time point The corresponding actuator action speed; (3) Threshold value judgment: Assuming that the operating speed threshold of the steam turbine actuator is v ₀ , use this threshold value v ₀ to make the following judgment on each differentially processed data v obtained in step (2): if v>v ₀ , it belongs to The effective data section of the steam turbine actuator opening step action test, record the start and end time of this section as t ₁ , t ₁ ′; if v<-v ₀ , it belongs to the steam turbine actuator closing step action test The effective data segment of , record the start and end time of this segment as t ₂ , t ₂ ′; (4), select the effective data section: subtract 1 second from the value of t ₁ or t ₂ obtained in step (3) respectively, add 1 second to the value of t ₁ ′ or t ₂ ′ obtained in step (3), respectively, the obtained The original measured data in the (t ₁ -1), (t ₁ ′+1) time period, including all valid data of the steam turbine actuator opening step action test; the obtained (t ₂ -1), (t ₂ '+1) The original measured data in the time zone includes all valid data of the step action test of the steam turbine actuator closing.