KR20120063634A - Condition monitoring apparatus and condition monitoring method for machinery system - Google Patents

Abstract

PURPOSE: A machine system status monitoring device and state monitoring method are provided to rapidly figure out an abnormal signal factor of a machine system because a failure analysis is performed by measuring data from the machine system according to the operation of the machine system. CONSTITUTION: A machine system status monitoring device comprises a data collecting unit(200) and state decision unit(300). The data collecting unit collects data from one or more sensors installed in the machine system according to an operation condition of the machine system. The state decision unit decides whether the machine system is normal or not by monitoring whether a vibration analysis value obtained from data within a set range among the data collected by the data collecting unit is within a set error range or not.

Description

Condition monitoring apparatus and condition monitoring method for machinery system

The present invention relates to a mechanical system state monitoring apparatus and state monitoring method for monitoring the state of the mechanical system to determine whether or not it is normal.

The monitoring system (or condition monitoring system, CMS) for the health assessment and maintenance of the mechanical system is to analyze the status of the mechanical system from the measurement signals and provide the operator with the current status. For this purpose, it is important to provide complex information in real time, such as output, vibration, temperature, oil condition, and stress in major parts, depending on the characteristics of the machine.

In general, since the data values in the steady state appear differently depending on the type of machine or the method of making the machine, the warning, alarm, etc. are changed when a certain value is changed after setting the initial normal state of the machine. It is necessary to generate a signal and inform the operator of the cause of the abnormal signal.

In particular, in the case of a wind power generator, a nacelle has a gear for increasing power generation by increasing the rotational speed by rotating the blade, power generation parts such as a generator for converting rotational energy into electrical energy, a gear and a generator, Highly volatile oil or lubricating oil used for the smooth mechanical operation of the same parts and plastic parts or various electrical parts are provided. When sparks are generated by these electric parts, ignition occurs due to volatile oil or lubricating oil. Because of the high risk of occurrence, it is necessary to measure data values to generate warnings and alarms.

On the other hand, if a warning or alarm occurs during CMS operation, the system operator should analyze the cause of the abnormal signal and resolve it. The initial set value and the cause of the simplified abnormal signal may reflect many operational histories while the system is operating. For long-term measurements, simplified measurements (e.g., 24 minutes per day average vibration or temperature) are used to determine the frequency components up to 5000 Hz for signal analysis (e.g. vibration signals up to 5000 Hz). More than 12500 samples per second to analyze).

Therefore, when the CMS abnormal signal is generated, most operators actually introduce a measurement system for precise analysis in the short term, and in some cases, there is a problem that the operation of the mechanical system must be stopped for precise analysis.

Also, in the process of determining whether the mechanical system is normal, the failure state is identified by monitoring the state of the mechanical system on the basis of all data and determining whether it is normal without any specific operating conditions. There is a problem that is not very easy to do.

It is an object of the present invention to provide a mechanical system state monitoring device and a state monitoring method for determining whether or not normal state by monitoring the state of a mechanical system while a certain operating condition is maintained for a certain time.

The mechanical system state monitor based on the inventor's operating condition according to claim 1 includes: a data collection unit for collecting data from at least one sensor installed in the mechanical system according to the operating condition of the mechanical system; And if the collected data is within the set range for a set time, whether the vibration analysis value data acquired from the data within the set range among the data collected in the data collection unit is within a set error range from the set value. And a state determination unit to determine whether the state of the mechanical system is normal.

According to the invention of claim 1, by analyzing the data from the mechanical system in accordance with the operation of the mechanical system to analyze the failure, it is possible to quickly determine the cause of the abnormal signal of the mechanical system to reduce the downtime of the mechanical system In addition, various types of signal evaluation enable cost savings in the maintenance and repair of mechanical systems. In particular, by monitoring the state of the mechanical system to determine whether it is normal while the operating conditions are maintained for a certain time, it is very easy to identify the failure state because the distribution of the vibration analysis value is small.

In the invention according to claim 1, the state determining unit retrieves data for a period set based on a current time to determine whether the state of the mechanical system is normal. Judge. According to the invention of claim 2, while the operating condition is maintained for a certain time, by monitoring the state of the mechanical system and searching for data for a desired period to determine whether it is normal, the failure state is identified because the dispersion of the vibration analysis value is small It is very easy to do.

In the invention according to claim 1, the vibration analysis value data of the mechanical system state monitor based on the operating condition of the inventor according to claim 3 represents a normal distribution of a function relationship with occurrence frequency.

According to the invention of Claim 3, it is very easy to grasp | ascertain the fault condition because the dispersion | variation of a vibration analysis value is small by monitoring the state of a mechanical system and determining whether it is normal, while an operation condition is maintained for a predetermined time.

The mechanical system condition monitoring value based on the inventors' operating condition according to claim 4, wherein the mechanical system is a wind power generator, and the data collection unit is proportional to the increase and decrease of the rotational speed of the rotor provided in the wind power generator. Collect data.

According to the invention of claim 4, by analyzing the data from the wind power generator in accordance with the operation of the wind power generator, it is possible to quickly determine the cause of the abnormal signal of the wind power generator to reduce the downtime of the wind power generator In addition, various types of signal evaluation can reduce the cost of wind turbine maintenance and repair.

In the invention according to claim 4, the vibration analysis value data is vibration analysis value data in a frequency domain obtained through a fast Fourier transform.

According to the invention of claim 5, by analyzing the data from the wind turbine in accordance with the operation of the wind turbine, it is possible to analyze the failure through the fast Fourier transform, so as to quickly determine the cause of the abnormal signal of the wind turbine generator downtime In addition to reducing the cost, the various types of signal evaluation can reduce the cost of wind turbine maintenance and repair.

In the invention according to claim 4, the data collection unit includes acceleration data of a gearbox, rotational speed data of a rotor, and the data collection unit of the invention according to claim 4; Collect temperature data for electrical generators, bearings and gearboxes.

According to the invention according to claim 6, the failure analysis by measuring the acceleration data of the gear box, the rotational speed data of the rotor, and the temperature data of the electrical generator, gear box, bearing provided in the wind power generator according to the operation of the wind generator By being able to do so, it is possible to quickly identify the cause of the abnormal signal of the wind power generator and to reduce the downtime of the wind power generator, and to reduce the cost of maintenance and repair of the wind power generator through various types of signal evaluation. .

The mechanical system condition monitor based on the inventor's operating condition according to claim 7 includes: a data collection step of collecting data from at least one sensor installed in the mechanical system in accordance with a driving condition of the mechanical system; Determining whether the collected data lasted for a set time within a set range; And if the collected data is within the setting range for a set time, whether the vibration analysis value data acquired from the data within the setting range among the data collected in the data collection step is within the setting error range from the setting value. And a state determination step of determining whether the state of the mechanical system is normal.

According to the invention of claim 7, it is possible to analyze the failure from the measurement of the data from the mechanical system in accordance with the operation of the mechanical system, it is possible to quickly determine the cause of the abnormal signal of the mechanical system to reduce the downtime of the mechanical system In addition, various types of signal evaluation enable cost savings in the maintenance and repair of mechanical systems. In particular, by monitoring the state of the mechanical system to determine whether it is normal while the operating conditions are maintained for a certain time, it is very easy to identify the failure state because the distribution of the vibration analysis value is small.

According to the present invention, by analyzing the data from the mechanical system in accordance with the operation of the mechanical system to analyze the failure, it is possible to quickly determine the cause of the abnormal signal of the mechanical system to shorten the downtime of the mechanical system as well as various This type of signal evaluation enables cost savings in the maintenance and repair of mechanical systems.

In addition, according to the present invention, by monitoring the state of the mechanical system while a certain operating condition is maintained for a certain time to determine whether it is normal, it is very easy to identify the failure state because the distribution of the vibration analysis value is small.

1 is a block diagram of a mechanical system state monitoring apparatus according to the present invention.
2 is a block diagram of a data collection unit according to the present invention.
3 is a graph illustrating a monitoring method according to an operating condition according to the present invention.
4 is a block diagram of a state determination unit according to the present invention.
5A is a graph illustrating a mechanical system state monitoring method when the present invention is not applied.
5B is a graph illustrating a mechanical system state monitoring method in accordance with the present invention.
6 is a flowchart of a mechanical system monitoring method according to the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, the embodiments of the present invention may be modified into various other forms, and the scope of the present invention is not limited to the embodiments described below. Shapes and sizes of the elements in the drawings may be exaggerated for clarity, elements denoted by the same reference numerals in the drawings are the same elements.

1 is a block diagram of a mechanical system state monitoring apparatus according to the present invention. Referring to FIG. 1, the state monitor of a mechanical system includes a data collection unit 200 and a state determination unit 300.

The data collection unit 200 collects data from at least one sensor 100 installed in the mechanical system according to the operation of the mechanical system. Sensors installed in the mechanical system includes an acceleration sensor 110, taco sensor 120, temperature sensor 130, weather sensor 140, an example of a mechanical system is a wind power generator.

The acceleration sensor 110 detects the acceleration data of the gear box provided in the mechanical system and generates an output signal with voltage, and the taco sensor 120 detects the rotational speed data of the rotor provided in the mechanical system and outputs it with voltage. Generate a signal. In addition, the temperature sensor 130 detects the temperature of the electricity generating unit, the gearbox, and the bearing provided in the mechanical system by resistance temperature detection (RTD), and the weather sensor 140 detects the wind direction and the wind speed. do.

In particular, when the mechanical system is a wind turbine, the rotational speed of the rotor may vary greatly according to the wind speed. The data collection unit 200 collects rotational speed data in proportion to the increase and decrease of the rotational speed of the rotor provided in the wind turbine. do. That is, if the rotational speed of the rotor is fast, the rotational speed data is collected at intervals with a large rotation angle. If the rotational speed of the rotor is slow, the rotational speed data is collected at regular angles by collecting the rotational speed data at small intervals. The result is the same as collecting. In this way, the rotational speed data can be collected at the same position of the rotor regardless of the rotational speed of the rotor.

The state determination unit 300 is a vibration obtained from the data within the setting range of the data collected in the data collection unit when the collected data lasts for a set time (details described later) within the setting range (detailed later) Monitors whether the analysis value data is within the set error range from the set value to determine whether the mechanical system is in a normal state.

To judge. In particular, during data collection, data is collected by searching data for a period of time set based on the current time. Specifically, the state determination unit 300 is the acceleration data, the rotational speed data, the temperature data, and the vibration analysis value data by the wind direction and wind speed data at the place where the wind turbine is installed from the set value (details described later) from the set error range If not within (details described later), an alarm such as a message or a warning sound is generated. The state determination process of the state determination unit 300 will be described later in detail. In this way, the state determination unit 300 may perform trend analysis to manage information on the wind turbine, generate a daily report of the wind turbine status, and transmit the result to an operator's e-mail or SMS (Short Message Service). have.

2 is a block diagram of a data collection unit according to the present invention. Referring to FIG. 2, the data collection unit 200 includes a timer means 210 and a data extraction means 200.

The timer means 210 counts the time and instructs the data extraction means 200 to extract data when the set time is reached, and the data extraction means 220 receives the data extraction instruction from the timer means 210. 140 extract data. For example, if it is set to extract the rotational speed data of the wind turbine at a predetermined time from 2 pm to 4 pm every day for one year, the timer means 210 is the data extraction means 220 when the predetermined time is reached. Instructs data extraction, and the data extraction means 220 extracts the rotational speed data of the wind turbine for the predetermined time after receiving the data extraction instruction.

3 is a graph illustrating a monitoring method according to an operating condition according to the present invention. Referring to FIG. 3, the taco sensor senses the rotational speed of the rotor provided in the wind turbine and shows the relationship of the rotational speed according to time. It can be seen that the rotational speed is periodically changed as time passes.

For example, you can set the wind speed generator data to be extracted at a specified time from 2 pm to 4 pm every day for one year, and then search the rotation data for the last week based on the current time. Can be represented. When the setting range is 20 to 25 rpm and the setting time is 5 minutes, when the rotation speed data lasts for more than 5 minutes within 20 to 25 rpm, the vibration analysis value data can be obtained from the rotation speed data.

Looking at the graph, from 2:10 pm to 2:16 pm lasted for 6 minutes within 20-25 rpm, and from 2:25 pm to 2:32 pm lasted for 7 minutes within 20-25 rpm. Therefore, vibration analysis value data is acquired based on the rotation speed data of such time.

4 is a block diagram of a state determination unit according to the present invention. Referring to FIG. 4, the state determination unit 300 includes an A / D (Analog / Digital) converter 310, a fast Fourier transform unit 320, a low pass filter 330, a high pass filter 340, and a band pass. And a filter 350, a band removing filter 360, and a comparison means 370.

Data collected by the data collection unit 200 is applied to the A / D converter 310, the A / D converter 310 is a device for converting an analog signal into a digital signal,

Convert analog signals to digital signals.

The digital signal converted by the A / D converter 310 is transferred to the fast Fourier transforming unit 320 and the filters 330 to 360, and the fast Fourier transforming unit 320 converts the digital signal into the fast Fourier transforming. By analyzing the frequency spectrum through to obtain the vibration analysis value data, each filter (330 ~ 360) filters the digital signal for each frequency band.

In addition, the vibration analysis value data from the frequency spectrum analysis result output from the fast Fourier transform means 320 and the output of the respective filters 330 to 360 are transmitted to the comparison means 370, the comparison means 370 is a vibration It is determined whether the state of the mechanical system is normal by monitoring whether the analysis value data is within the set error range from the set value. In other words, when the state of the mechanical system is judged, if the vibration analysis value data is within the setting error range from the set value, the mechanical system is determined to be normal. In particular, the fast Fourier transform on the digital signal may be performed in real time at the same time as the data collection unit 200 collects the data, or may be performed later using the already collected data.

5A is a graph illustrating a mechanical system state monitoring method when the present invention is not applied, and FIG. 5B is a graph illustrating the mechanical system state monitoring method according to the present invention. 5A and 5B, in FIG. 5A and FIG. 5B, the relationship between the frequency of occurrence according to the vibration analysis values is shown in a graph, and it can be seen that the functional relationship indicates a normal distribution.

5A and 5B, when a1 <a2 <a3 <a4 <a5 <a6 <a7 <a8 <a9, the distribution range of the vibration analysis value is larger in FIG. 5A than in FIG. It can be seen that the range of the vibration analysis value having is large. The reason for this is that unlike the case of FIG. 5B, in the case of FIG. 5A, all of the collected rotational data is extracted from the collected rotational data without extracting the rotational speed data when the rotational speed data is maintained for a set time within a set range. This is because the vibration analysis value data is obtained on the basis.

From this result, it can be seen that in the case of FIG. 5B, when determining whether the mechanical system is normal than in the case of FIG. In particular, in the case of a wind power generator as an example of a mechanical system, the rotation speed is severely changed, and it can be easily applied to a state in which the vibration is severely changed according to the change of the rotation speed. In other words, despite the severe fluctuations in rotation speed, it is not necessary to analyze vibrations from all collected rotational speed data, thereby simplifying the analysis process.

6 is a flowchart of a mechanical system monitoring method according to the present invention. 6 will be described together with FIG. 1.

First, the data collection unit 200 collects data from at least one sensor installed in the mechanical system according to the operating conditions of the mechanical system (S100). Sensors installed in the mechanical system include an acceleration sensor 110, taco sensor 120, temperature sensor 130, weather sensor 140, etc., the data collection unit 200 from these acceleration data, rotational speed data, Temperature data and wind direction and wind speed data at the place where the wind turbine is installed are collected.

After the step S100, the state determination unit 300 determines whether the data collected by the data collection unit 200 lasted for a set time within the set range (S200). For example, the rotation speed data is 20 Determine if it lasts more than 5 minutes within ~ 25rpm.

After the step S200, when the data collected by the data collection unit 200 is maintained for a set time within the setting range, the state determination unit 300, the data within the setting range of the data collected by the data collection unit 200 It is monitored whether or not the vibration analysis value data obtained from the set error range from the set value (S300). For example, when the condition of determining whether the mechanical system is normal in step S200 is satisfied, as shown in FIG. 4, the time range is from 2:10 pm to 2:16 pm and from 2:25 pm to 2:32 pm The vibration analysis value data is obtained based on the rotational speed data of the time range up to minutes.

After the step S300, if the vibration analysis value data obtained in step S200 is within the set error range from the set value, it is determined that the mechanical system is in a normal state (S410). However, if the vibration analysis value data is not within the set error range from the set value, the state determination unit 300 determines that the mechanical system is not in the normal state (S420). That is, in FIG. 5B, whether the mechanical system is normal is determined according to whether or not it is within a setting error range of a5-a4 (or a6-a5) from a setting value of a5. For example, if the set value is 30dB and the set error range is 5dB, it is judged that the mechanical system is in a normal state only when the vibration analysis value data is 25 to 35dB, and when it has other values, the mechanical system is normal. It is judged that it is not in a state.

The present invention is not limited by the above-described embodiment and the accompanying drawings. It is intended that the scope of the invention be defined by the appended claims, and that various forms of substitution, modification, and alteration are possible without departing from the spirit of the invention as set forth in the claims. Will be self-explanatory.

100: sensor 110: acceleration sensor
120: taco sensor 130: temperature sensor
140: weather sensor 200: data collection unit
210: timer means 220: data extraction means
300: state determination unit 310: A / D converter
320: high speed Fourier transform means 330: low pass filter
340: high pass filter 350: band pass filter
360: band elimination filter 370: comparison means

Claims (7)

A data collector configured to collect data from at least one sensor installed in the mechanical system according to an operating condition of the mechanical system; And
When the collected data lasts for a set time within the set range, by monitoring whether the vibration analysis value data acquired from the data within the set range of the data collected in the data collection unit is within the set error range from the set value A state determination unit that determines whether the state of the mechanical system is normal;
A mechanical system status monitoring device comprising a. The method of claim 1,
And the state determination unit determines whether the state of the mechanical system is normal by searching for data for a period of time set based on a current time. The method of claim 1,
And said vibration analysis value data indicates a normal distribution of a function relationship with frequency of occurrence. The method of claim 1,
The mechanical system is a wind power generator,
The data collection unit collects data in proportion to the increase and decrease of the rotational speed of the rotor provided in the wind turbine, mechanical system state monitoring device. The method of claim 4, wherein
The vibration analysis value data is a vibration analysis value data in the frequency domain obtained through a fast Fourier transform. The method of claim 4, wherein
The data collector, provided in the wind power generator,
Acceleration data of the gearbox,
Rotational speed data of the rotor, and
Electricity generator, bearing, temperature data of the gearbox
Machine condition monitoring system. A data collection step of collecting data from at least one sensor installed in the mechanical system according to an operating condition of the mechanical system;
Determining whether the collected data lasted for a set time within a set range; And
When the collected data lasts for a set time within the set range, by monitoring whether the vibration analysis value data acquired from the data within the set range of the data collected in the data collection step is within the set error range from the set value A state determination step of determining whether the state of the mechanical system is normal;
A mechanical system status monitoring method comprising a.

Images