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CN109826816B - Intelligent early warning system and method for fan stall - Google Patents

Intelligent early warning system and method for fan stall Download PDF

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Publication number
CN109826816B
CN109826816B CN201811642240.6A CN201811642240A CN109826816B CN 109826816 B CN109826816 B CN 109826816B CN 201811642240 A CN201811642240 A CN 201811642240A CN 109826816 B CN109826816 B CN 109826816B
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fan
data
stall
time
early warning
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CN109826816A (en
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杨建国
金宏伟
赵虹
范海东
裘立春
滕敏华
项群扬
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Zhejiang University ZJU
Zhejiang Energy Group Research Institute Co Ltd
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Zhejiang University ZJU
Zhejiang Energy Group Research Institute Co Ltd
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Abstract

本发明公开了一种风机失速智能预警系统与方法。本发明包括信号采集与预处理模块、数据计算模块、智能分析模块、预警报警模块;信号采集与预处理模块,用于从自动控制系统采集风机运行的当前时间的前的一段时间T内的历史数据,并对历史数据进行分析和处理,得到有价值的历史数据曲线信息;数据计算模块,用于计算数据变化趋势,并根据信号周期获得可靠的实时数据值及其数据偏差;智能分析模块,用于根据数据变化趋势、实时数据值、数据偏差等评估风机失速的倾向性或失速状态;预警报警模型,用于在风机出现失速倾向或已发生失速时,提供预警或报警信息。本发明在风机完全失速前数分钟进行预警,为消除失速提供充足的干预时间。

Figure 201811642240

The invention discloses a fan stall intelligent early warning system and method. The invention includes a signal acquisition and preprocessing module, a data calculation module, an intelligent analysis module, and an early warning and alarm module; the signal acquisition and preprocessing module is used to collect the history within a period of time T before the current time of fan operation from the automatic control system data, and analyze and process the historical data to obtain valuable historical data curve information; the data calculation module is used to calculate the data trend, and obtain reliable real-time data values and data deviations according to the signal cycle; the intelligent analysis module, It is used to evaluate the tendency of the fan to stall or the stall state according to the data change trend, real-time data value, data deviation, etc.; the early warning alarm model is used to provide early warning or alarm information when the fan has a stall tendency or has stalled. The present invention provides an early warning several minutes before the fan is completely stalled, and provides sufficient intervention time for eliminating the stall.

Figure 201811642240

Description

Intelligent early warning system and method for fan stall
Technical Field
The invention belongs to the technical field of production safety, and relates to an intelligent early warning system and method for fan stall.
Background
When a fan is in a normal working condition, an attack angle is small (an included angle between an airflow direction and a blade chord of the blade is an attack angle), airflow bypasses an airfoil-shaped blade to keep a streamline state, when the airflow forms a positive attack angle with an inlet of the blade, namely α is greater than 0, and the positive attack angle exceeds a certain critical value, the flow working condition of the back of the blade begins to deteriorate, a boundary layer is damaged, a vortex region appears at the tail end of the back of the blade, namely a 'stalling' phenomenon is generated.
Disclosure of Invention
In view of the limitations of the prior art and the development trend of the intelligent technology, the invention provides an intelligent early warning system and method for the stall of a fan.
The technical scheme adopted by the invention for solving the technical problems is as follows:
the system comprises a signal acquisition and preprocessing module, a data calculation module, an intelligent analysis module and an early warning and alarming module.
The signal acquisition and preprocessing module is used for acquiring historical data in a period of time T before the current time of fan operation from the automatic control system, analyzing and processing the historical data to obtain valuable historical data curve information, and is specifically realized as follows:
historical data in a period of time T before the current time of fan operation are collected from an automatic control system, wherein the historical data comprise: fan current, movable vane opening, fan flow, inlet and outlet differential pressure. The length of the time period T and the time interval of the data points are set according to the data characteristics, generally, the time period T is 1-10 minutes, and the shorter the time period is, the more sensitive the reaction is; the time interval is generally 1 second and needs to be comprehensively determined according to the data frequency and the data processing speed requirement of the automatic control system. And smoothing the collected historical data by using average moving or other mathematical methods, eliminating noise signals of a historical data curve, and removing abnormal values. And calculating the data fluctuation period of the preprocessed historical data by a mathematical method.
The data calculation module is used for calculating a data change trend (derivative) and obtaining a reliable real-time data value and a data deviation thereof according to a signal period, and specifically comprises the following steps:
according to the data fluctuation period obtained by the signal acquisition and preprocessing module, averaging the preprocessed historical data according to the period to obtain a stable curve reflecting the real data characteristics, and then respectively calculating the change slope of the periodic average curve of the fan current, the movable blade opening, the fan flow and the inlet-outlet differential pressure by using a derivative method. And calculating the average value of the last period according to the data fluctuation period as a real-time data value, and calculating the variation of historical data within one minute, namely data deviation, including fan current, fan flow and inlet-outlet differential pressure.
The intelligent analysis module is used for evaluating the tendency or stall state of the fan stall according to data change trend, real-time data values, data deviation and the like, and specifically comprises the following steps:
diagnosis of the tendency of the fan to stall: and judging whether the fan current, the fan flow, the inlet-outlet differential pressure and the movable vane opening degree exceed respective limit values or not according to the fan current, the fan flow, the inlet-outlet differential pressure and the change slope of the movable vane opening degree respectively, and if the fan current, the fan flow, the inlet-outlet differential pressure and the movable vane opening degree exceed the respective limit values, judging that the fan has stall tendency. The overall logic is: if the opening degree of the movable blade continuously increases or reaches the maximum value, the current of the fan, the flow of the fan and the inlet-outlet differential pressure are continuously reduced, and the respective change speeds exceed respective limit values, the stalling is indicated to be imminent. The variation limit value of each parameter is determined by the operation characteristics of a specific fan, big data analysis is needed according to historical data, and then supplement and verification are carried out through necessary tests.
And (3) diagnosing a stalling state of the fan: and establishing a relation model between the fan current, the fan flow, the inlet-outlet pressure difference and the movable blade opening degree by utilizing the big data, wherein the relation model comprises an average value relation and a normal region relation, for example, the fan runs under 70% of movable blade opening degree, and the fan current average value Av and the fluctuation range As of normal running under the movable blade opening degree in the historical big data are calculated. The overall logic is: if the opening degree of the movable blades is continuously increased or reaches the maximum value, the real-time values of the fan current, the fan flow and the inlet-outlet differential pressure respectively deviate from the minimum value ranges (Av-As, Fv-Fs and Pv-Ps) of the fan current, the fan flow and the inlet-outlet differential pressure corresponding to the real-time values of the opening degree of the movable blades, and the fan is in the stall state.
The early warning and alarming model is used for providing early warning or alarming information when the fan has a stalling tendency or has stalled.
When the fan has a stall tendency, performing stall early warning, wherein the early warning color is yellow;
and when the fan is in a stall state, performing stall alarm, wherein the alarm color is red.
The early warning and alarming modes comprise sound, light, pop-up frames and other striking modes.
The invention has the following beneficial effects:
according to the method, the key parameters of the stall of the fan are preprocessed through a computer intelligent analysis technology to obtain effective signal information, further obtain the effective change trend of the key parameters, and then obtain the trend relation of related parameters of the stall of the fan through historical big data analysis and fan characteristic analysis (possibly needing tests), so that the tendency of the stall of the fan is analyzed in real time, early warning can be performed minutes before the fan completely stalls, and sufficient intervention time is provided for stall elimination.
Drawings
FIG. 1 is a flow chart of the system and method of the present invention.
Detailed Description
The invention will be further explained with reference to the drawings.
As shown in fig. 1, the intelligent early warning system and method for fan stall includes a signal acquisition and preprocessing module ①, a data calculation module ②, an intelligent analysis module ③, and an early warning module ④.
The signal collecting and preprocessing module ① is used for collecting historical data of the fan in a period of time before the current time of operation from the automatic control system, and analyzing and processing the data signal to obtain valuable historical data curve information.
The data calculating module ② is used to calculate the data variation trend (derivative) and obtain reliable real-time data and its variation amplitude (data deviation) according to the signal period.
The intelligent analysis module ③ is used for estimating the tendency of the fan stall or the stall state according to the data change trend, the real-time value, the data deviation and the like.
The early warning model ④ is used for providing early warning or warning information when the fan is in a stalling tendency or has stalled.
The signal collection and preprocessing module ① collects historical data from the automatic control system in a period of time before the current time of fan operation, wherein the data includes fan current, movable blade opening, fan flow, inlet and outlet differential pressure, the length of the time period and data point time interval are set according to data characteristics, generally, the time period is 1-10 minutes, the shorter the time period is, the more sensitive the reaction is, the time interval is generally 1 second, and the time interval is determined comprehensively according to the data frequency of the control system and the data processing speed requirement.
The data calculation module ② averages the preprocessed historical data according to the period according to the obtained data change period to obtain a stable curve representing the characteristics of real data, and then calculates the slope of the periodic average curve of the fan current, the movable vane opening, the fan flow and the inlet-outlet differential pressure by using a derivative method, and calculates the average value of the last period according to the data period as a real-time value, and calculates the variation of the data within one minute, namely the data deviation, including the fan current, the fan flow and the inlet-outlet differential pressure.
The intelligent analysis module ③ judges whether the fan stall tendency exceeds the respective limit value according to the change slopes of the fan current, the fan flow, the inlet-outlet differential pressure and the movable vane opening, if the change slopes exceed the respective limit values, the fan stall tendency is judged, the general logic is that the fan stall tendency is about to occur if the movable vane opening continuously increases or reaches the maximum value, the fan current, the fan flow and the inlet-outlet differential pressure continuously decrease, and the respective change speeds exceed the respective limit values, the sizes of the change limit values of the parameters are determined by the operation characteristics of the specific fan, large data analysis is needed according to historical data, and then supplement and verification are carried out through necessary tests.
The intelligent analysis module ③ diagnoses the stall state of the fan, and establishes a relationship model between the fan current, the fan flow, the inlet-outlet differential pressure and the rotor blade opening degree by using big data, wherein the relationship model comprises a mean value relationship and a normal region relationship, for example, the fan operates under 70% of the rotor blade opening degree, and the general logic of calculating the fan current mean value Av and the fluctuation range As. of the normal operation under the rotor blade opening degree in the historical big data at the moment is that if the rotor blade opening degree is continuously increased or reaches the maximum value, the real-time values of the fan current, the fan flow and the inlet-outlet differential pressure respectively deviate from the minimum value ranges (Av-As, Fv-Fs and Pv-Ps) of the fan current, the fan flow and the inlet-outlet differential pressure corresponding to the rotor blade opening degree real-time values, and the fan is.
The early warning module ④ performs stall early warning when the fan has a stall tendency, the early warning color is yellow, and performs stall warning when the fan is in a stall state, the warning color is red.

Claims (4)

1.一种风机失速智能预警系统,其特征在于包括信号采集与预处理模块、数据计算模块、智能分析模块、预警报警模块;1. an intelligent early warning system for fan stall, it is characterized in that comprising signal acquisition and preprocessing module, data calculation module, intelligent analysis module, early warning alarm module; 所述的信号采集与预处理模块,用于从自动控制系统采集风机运行的当前时间的前的一段时间T内的历史数据,并对历史数据进行分析和处理,得到有价值的历史数据曲线信息;The signal acquisition and preprocessing module is used to collect historical data from the automatic control system in a period of time T before the current time of fan operation, and analyze and process the historical data to obtain valuable historical data curve information. ; 所述的数据计算模块,用于计算数据变化趋势,并根据信号周期获得可靠的实时数据值及其数据偏差;The data calculation module is used to calculate the data change trend, and obtain reliable real-time data values and data deviations according to the signal period; 所述的智能分析模块,用于根据数据变化趋势、实时数据值、数据偏差评估风机失速的倾向性或失速状态;The intelligent analysis module is used for evaluating the tendency or stall state of the fan to stall according to the data change trend, real-time data value and data deviation; 所述的预警报警模块,用于在风机出现失速倾向或已发生失速时,提供预警或报警信息;The early warning and alarm module is used to provide early warning or alarm information when the fan has a tendency to stall or has stalled; 所述的信号采集与预处理模块,具体实现如下:The signal acquisition and preprocessing module is specifically implemented as follows: 从自动控制系统采集风机运行的当前时间前的一段时间T内的历史数据,历史数据包括:风机电流、动叶开度、风机流量、进出口差压;时间段T的长度和数据点的时间间隔根据数据特征设置,时间段T为1-10分钟,时间段越短,反应越灵敏;时间间隔为1秒,需要根据自动控制系统数据频率和数据处理速度要求来综合确定;然后将采集到的历史数据利用平均移动方法进行平滑处理,消除历史数据曲线的噪声信号,并去除异常值;再将预处理的历史数据利用数学方法计算其数据波动周期。Collect historical data from the automatic control system for a period of time T before the current time when the fan is running. The historical data includes: fan current, blade opening, fan flow, differential pressure between inlet and outlet; the length of time period T and the time of the data point The interval is set according to the data characteristics, the time period T is 1-10 minutes, the shorter the time period, the more sensitive the response; the time interval is 1 second, which needs to be comprehensively determined according to the data frequency and data processing speed requirements of the automatic control system; The historical data is smoothed by the average moving method, the noise signal of the historical data curve is eliminated, and the outliers are removed; then the preprocessed historical data is mathematically calculated to calculate its data fluctuation period. 2.根据权利要求1所述的一种风机失速智能预警系统,其特征在于所述的数据计算模块具体实现如下:2. a kind of fan stall intelligent early warning system according to claim 1, is characterized in that described data calculation module is specifically realized as follows: 根据信号采集与预处理模块得到的数据波动周期,将预处理的历史数据按周期进行平均,得到体现真实数据特征的平稳曲线,再利用导数方法分别计算风机电流、动叶开度、风机流量、进出口差压的周期平均曲线的变化斜率;并根据数据波动周期计算最后一周期的平均值,作为实时数据值,并计算一分钟内历史数据的数据偏差,包括风机电流、风机流量、进出口差压。According to the data fluctuation cycle obtained by the signal acquisition and preprocessing module, the preprocessed historical data is averaged by cycle to obtain a smooth curve reflecting the characteristics of the real data, and then the derivative method is used to calculate the fan current, rotor blade opening, fan flow, The change slope of the cycle average curve of the differential pressure between the inlet and outlet; and calculate the average value of the last cycle according to the data fluctuation cycle, as the real-time data value, and calculate the data deviation of the historical data within one minute, including the fan current, fan flow, import and export differential pressure. 3.根据权利要求2所述的一种风机失速智能预警系统,其特征在于所述的智能分析模块具体实现如下:3. a kind of fan stall intelligent early warning system according to claim 2 is characterized in that described intelligent analysis module is specifically realized as follows: 风机失速倾向性诊断:分别根据风机电流、风机流量、进出口差压、动叶开度的变化斜率,判断风机电流、风机流量、进出口差压、动叶开度是否超过各自的限值,如果都超过各自限值,则判断为风机有失速倾向性;如果动叶开度持续增大或已经达到最大值,风机电流、风机流量、进出口差压都持续减小,且各自的变化速度超过各自限值,则表现为即将失速;各参数的变化限值的大小由具体风机的运行特性进行确定,需要根据历史数据进行大数据分析,再通过必要的试验进行补充和验证;Diagnosis of fan stall tendency: according to the change slope of fan current, fan flow, inlet and outlet differential pressure, and moving blade opening, determine whether the fan current, fan flow, inlet and outlet differential pressure, and moving blade opening exceed their respective limits. If they all exceed their respective limits, it is judged that the fan has a tendency to stall; if the opening of the moving blades continues to increase or has reached the maximum value, the fan current, fan flow, and differential pressure between inlet and outlet continue to decrease, and their respective speed of change If it exceeds the respective limits, it will appear as stalling; the magnitude of the change limit of each parameter is determined by the operating characteristics of the specific fan, and it is necessary to conduct big data analysis according to historical data, and then supplement and verify it through necessary tests; 风机失速状态诊断:利用大数据建立风机电流、风机流量、进出口压差与动叶开度之间的关系模型,关系模型包括均值关系和正常区域关系,计算历史大数据中在指定动叶开度下正常运行的风机电流平均值Av和波动范围As;如果动叶开度持续增大或已经达到最大值,风机电流、风机流量、进出口差压的实时值分别偏离动叶开度实时值对应的风机电流、风机流量、进出口差压的最小值范围,则说明风机已经处于失速状态。Fan stall status diagnosis: use big data to establish a relationship model between fan current, fan flow, inlet and outlet pressure difference and rotor blade opening. The relationship model includes mean value relationship and normal area relationship. The average value Av of the fan current and the fluctuation range As of the normal operation under the temperature; if the opening of the moving blade continues to increase or has reached the maximum value, the real-time values of the fan current, fan flow, and inlet and outlet differential pressure deviate from the real-time value of the moving blade opening. The corresponding minimum range of fan current, fan flow, and inlet and outlet differential pressure indicates that the fan has been in a stall state. 4.根据权利要求3所述的一种风机失速智能预警系统,其特征在于所述的预警报警模块具体实现如下:4. a kind of fan stall intelligent early warning system according to claim 3 is characterized in that described early warning alarm module is specifically realized as follows: 当风机出现失速倾向时,进行失速预警,预警色为黄色;When the fan has a tendency to stall, a stall warning is performed, and the warning color is yellow; 当风机已处于失速状态时,进行失速报警,报警色为红色。When the fan is already in the stall state, the stall alarm is performed, and the alarm color is red.
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CN112132485A (en) * 2020-09-30 2020-12-25 上海众源网络有限公司 An index data processing method, device, electronic device and storage medium
CN114064760B (en) * 2021-11-18 2022-12-13 广州泰禾大数据服务有限公司 Multi-dimensional early warning analysis and judgment method for data
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