CN103913193A - Device fault pre-maintenance method based on industrial wireless technology - Google Patents

Abstract

The invention relates to a device fault pre-maintenance method based on an industrial wireless technology. In the method, through data communication of an industrial wireless network and an industrial Ethernet, real-time monitoring and fault pre-maintenance are performed on an on-site device. The method includes the following steps: an upper computer performs parameter configuration on on-site instruments, which are used for monitoring the device, through the industrial Ethernet and the industrial wireless network; the instruments acquire sensor information of the on-site device according to the parameter configuration and upload result data, which is obtained after local processing of the sensor information, to the upper computer through the industrial wireless network and the industrial Ethernet; the upper computer performs fault diagnosis according to the result data and judges the operation state of the device; and if the fault diagnosis result is obtained, on-site maintenance personnel are notified through a fault alarm so as to maintain the device.

Description

A method of equipment failure pre-maintenance based on industrial wireless technology

technical field

The present invention relates to a method of equipment fault pre-maintenance based on industrial wireless technology, specifically a wireless fault pre-diagnosis for rotating machinery (motors, fans, pumps, etc.) based on vibration, voltage, current, temperature and other signals method.

Background technique

With the advancement of technology, the modern process industry is developing in the direction of large-scale, integrated, automated and high-speed. The production process has higher and higher requirements for the reliability of equipment operation, which requires continuous, efficient and long-term operation under harsh working conditions. Unexpected failure of key equipment in the process industry will cause serious economic losses, even catastrophic consequences of casualties and severe environmental pollution. Therefore, building an efficient and reliable mechanical equipment maintenance system is an effective means to reduce costs, increase profits, and enhance corporate competitiveness.

Traditional equipment maintenance methods adopt maintenance strategies such as "after-event maintenance" and "regular maintenance". Under the premise of not affecting the production process, the comprehensive utilization of sensor, detection, communication, computer and artificial intelligence and other technologies can monitor the operation status of key equipment in real time, which can identify hidden troubles, locate the root cause of failures, and predict the development trend of failures. , a comprehensive technique that provides a troubleshooting strategy.

Currently, condition-based maintenance is only applied in large-scale key core equipment due to its high implementation cost. For small and medium-sized enterprises, there are still a large number of key equipment in the vacuum zone of monitoring, and their daily maintenance still adopts the method of regular maintenance. Therefore, it has important application value to provide a low-cost fault diagnosis solution based on condition-based maintenance. In addition, to integrate fault diagnosis systems in a large number of established enterprises, the cost and construction cost of laying cables are not only high, but also the system reconfiguration is difficult and the reliability is low. The industrial wireless technology can solve these problems very well. The industrial wireless technology eliminates the dead angle of the traditional wired measurement and control system, and broadens the time and space dimensions of the measurement and control system.

In petrochemical, metallurgical and electric power enterprises, motors, fans, compressors, pumps and other equipment are key equipment, and their working status needs to be monitored in real time to achieve condition-based maintenance. During the operation of these devices, some faults will occur, such as rotor imbalance or impact, rolling and mutual friction between parts, gaps or looseness between parts, peeling or cracks on the surface of parts, etc., which will cause equipment voltage, Signals such as current, temperature, and vibration are abnormal. Therefore, monitoring these signals can effectively monitor the status of the equipment.

Contents of the invention

In order to overcome the deficiencies of the current prior art, the present invention provides a method for equipment failure pre-maintenance based on industrial wireless technology. The technical solution adopted in the present invention is:

A device fault pre-maintenance method based on industrial wireless technology, through data communication of industrial wireless network and industrial Ethernet, real-time monitoring and fault pre-maintenance of field devices; including the following steps:

The upper computer configures the parameters of the instruments used to monitor the equipment on site through the industrial Ethernet and industrial wireless network; the instrument collects the sensor information of the field devices according to the parameter configuration, and the result data after local processing of the sensor information is passed through the industrial wireless network, Industrial Ethernet is uploaded to the host computer;

The upper computer performs fault diagnosis based on the result data, and judges the operating status of the equipment; if the type of fault is obtained, the on-site maintenance personnel are notified through the fault alarm to repair the equipment.

The equipment includes motors, fans, pumps, compressors.

The parameter configuration includes sampling frequency, refresh period, threshold, instrument working mode, data collection time, and sensor channel number.

The sensor information includes voltage, current, temperature, and vibration information.

In the local processing, performing local processing on the vibration sensor information includes:

The vibration acceleration data collected by the vibration sensor is obtained through an integral operation to obtain the vibration velocity data, and the vibration intensity is obtained according to the vibration velocity data;

Fast Fourier transform is performed on the vibration acceleration data collected by the vibration sensor to obtain the frequency spectrum of the vibration acceleration, and the amplitude of the specified frequency component is obtained according to the frequency spectrum;

The vibration acceleration data collected by the vibration sensor is compressed to obtain compressed data.

The result data includes voltage, current, temperature data, vibration intensity, amplitude of specified frequency components, and compressed data.

The upper computer performs fault diagnosis according to the result data, and judging the operating state of the equipment includes the following steps: input the result data into the fault diagnosis database, and obtain the fault through the result data, equipment parameters, result history data, threshold and fault type in the fault diagnosis database. Types of fault diagnosis results.

The thresholds include thresholds for voltage, current, temperature data, vibration intensity, and amplitude of specified frequency components.

The fault alarm can also send alarm information and maintenance suggestions to field equipment maintenance personnel in the form of mobile phone information through local sound and light alarm or 3G network.

The present invention has the following beneficial effects and advantages:

1. The present invention adopts industrial wireless technology as the networking mode, which improves the flexibility of networking, enhances the reliability of the system, eliminates the dead angle of the traditional wired measurement and control system, and broadens the time and space dimensions of the measurement and control system.

2. The present invention realizes state-based maintenance of equipment such as motors, pumps, fans, etc., improves the efficiency of equipment maintenance, reduces the cost of equipment maintenance, and enhances the reliability of equipment work.

3. The combination of local sound and light alarm and 3G mobile phone network alarm enables equipment maintenance personnel to grasp the current working status of the equipment anytime and anywhere, ensuring the timeliness of equipment maintenance.

Description of drawings

Fig. 1 overall structural diagram of the fault pre-maintenance system based on industrial wireless technology of the present invention;

Fig. 2 industrial wireless communication schematic diagram of the present invention;

Figure 3 Structural diagram of on-site monitoring subsystem;

Figure 4 wireless transmitter work flow chart;

Figure 5 Diagnosis flow chart of the fault diagnosis center.

Detailed ways

The present invention will be further described in detail below in conjunction with the examples.

The field instrument monitors the status of the controlled object in real time, collects different data information, performs data processing and preliminary fault diagnosis locally, and then transmits the compressed data to the factory-level monitoring center through the wireless network for fault diagnosis. The local monitoring center cannot identify Faults can be submitted to the remote fault monitoring center for consultation by experts. The fault results are displayed in various ways such as local instruments and monitoring centers, and support the transmission of results by 3G network smartphones.

An equipment failure pre-maintenance system based on industrial wireless technology, including the composition structure of the system, the working mode of wireless instruments, the composition mode of wireless network, the factory-level fault monitoring center and remote fault diagnosis expert service center for fault diagnosis, and support for fault diagnosis Diagnosis results are notified to equipment maintenance personnel through multimedia methods such as text, graphics, audio, and video through the 3G network. The entire fault pre-maintenance system can be used for fault diagnosis and equipment pre-maintenance of rotating machinery such as motors, fans, and pumps.

The invention provides a solution for equipment failure pre-maintenance based on industrial wireless. The wireless instrument collects signals such as voltage, current, temperature, vibration, etc. Perform preprocessing and primary signal analysis locally, realize primary fault analysis and alarm through threshold judgment, and then send the compressed time domain and frequency domain signals to the factory-level monitoring center through the wireless ad hoc network for advanced fault diagnosis and judgment of equipment Operating status, distinguishing the type and degree of faults, giving maintenance suggestions, and realizing pre-maintenance. Faults that cannot be diagnosed in the factory-level diagnostic center are sent to the remote fault diagnosis expert service center through the Internet, and the field experts conduct consultations, and then return the diagnosis results to the factory-level fault diagnosis center. Fault diagnosis results can be displayed at different levels such as local instruments, plant-level monitoring center, and remote diagnosis center. It supports sending information such as failure alarms to the smartphones of equipment maintenance personnel through the 3G network to realize full-time and space-time monitoring of equipment.

Fig. 1 is an overall system structure diagram of a fault pre-maintenance system based on industrial wireless technology. This system consists of a field instrument system 60, an industrial wireless data transmission network 40, an industrial Ethernet 30, and a fault diagnosis and fault alarm notification system. According to the specific monitoring requirements, there may be multiple on-site monitoring subsystems 60. For example, the systems distributed in different workshops at the industrial site can be configured into their own monitoring subsystems. The types and quantities of wireless instruments used in each subsystem are based on the monitoring objects. The nature of is specifically determined. The data from the field wireless instrument is connected to the wireless data transmission network 40 through the wireless communication signal 50, and the industrial wireless gateway 41 in the 40 transmits the data to the industrial Ethernet. The factory-level fault diagnosis center 12 performs data processing on signals such as vibration, voltage, current, and temperature of the monitored objects from the industrial site, analyzes the current working status of the equipment, determines whether the equipment is faulty, and if a fault occurs, locate the fault location. Determine the type of failure and give reasonable equipment maintenance suggestions. Limited by the development of current artificial intelligence technology, no fault diagnosis expert system can solve all fault diagnosis problems. If the factory-level fault diagnosis center 12 encounters difficulties in the fault diagnosis process, the diagnostic task will be sent to the remote fault diagnosis center through the Internet 20. The diagnostic expert service center 13 requests assistance from domain experts. The experts in the field return the diagnostic results to the factory-level fault diagnosis center 12 through the Internet 20. If the factory-level fault diagnosis center 12 finds a fault, the fault alarm notification system 14 will report the alarm information, fault location, fault type, and suggested treatment measures Sent to the equipment maintenance personnel responsible for the safe operation of the equipment. In view of the current development of 3G mobile communication technology and mobile Internet technology, the fault alarm notification system supports multimedia information transmission; for example, it notifies equipment maintenance personnel in the form of mobile phone text messages. The wireless network server 11 completes the configuration and maintenance of the on-site industrial wireless instruments and the industrial wireless data transmission network 40 . Through the wireless network server 11, operations such as starting and stopping, parameter configuration, and fault maintenance of wireless instruments distributed on industrial sites can be realized.

Parameter configuration includes sampling frequency, refresh cycle, threshold, instrument working mode, data collection time, sensor channel number; threshold includes vibration intensity threshold, vibration acceleration spectrum specified frequency component amplitude threshold, temperature threshold, voltage threshold and current threshold; instrument work Modes include normal operating mode and power saving mode.

Fig. 2 is a schematic diagram of the industrial wireless communication of the present invention. The wireless network is composed of an industrial wireless gateway 41 , a wireless router 42 and a wireless instrument 43 . The specific wireless communication technology selected can be WIA (Wireless Networks for Industrial Automation), Wireless HART, ISA100 and other methods. The type of the wireless instrument 43 can be a wireless vibration transmitter, a wireless current transmitter, a wireless voltage transmitter, a wireless temperature transmitter, etc., and the specific type is determined according to the diagnosis object. The communication mode of the wireless instrument 43 and the wireless gateway 41 is determined according to the distance between the two, if the distance between the two is in the distance of one hop of the wireless instrument 43, then the wireless instrument 43 and the wireless gateway 41 communicate directly; If the distance between them is greater than the distance of one hop, then a wireless router 42 is installed at a suitable position between the wireless instrument 43 and the wireless gateway 41 to relay the data. The wireless network 40 is a self-organizing mesh network, which supports automatic joining and exiting of devices. Therefore, the network has easy configuration and high reliability.

Figure 3 is a structural diagram of the on-site monitoring subsystem. The system consists of detected objects 69, sensors 62, 64, 66, 68, and wireless transmitters 61, 63, 65, and 67. The sensors convert physical signals that are helpful for fault diagnosis into electrical signals. For example, the signals can be voltage , current, temperature, and vibration signals, of course, are not limited to these signals, and can also be other signals such as sound, image, etc. The specific type should be determined according to the type of monitoring object and the nature of the fault to be diagnosed. For example, if the monitoring object 69 is a unit composed of a motor-water pump, it is possible to use a voltage sensor 64 and a current sensor 66 to monitor the voltage and current of the motor in the measured object 69 respectively to carry out fault monitoring, and the sensor detects The signal is sent to the wireless voltage transmitter 63 and the wireless current transmitter 65 for processing; the temperature sensor 62 is used to monitor the bearing bush temperature of the load end motor of the unit, and the signal is sent to the wireless temperature transmitter 61 for processing; multiple vibration sensors are used to 68 detects the vibration signals in the X, Y, and Z directions of multiple measuring points of the unit, and sends the results to multiple corresponding wireless vibration transmitters 67 for processing. The data processed by each wireless transmitter is sent to the industrial wireless communication network 40 through wireless signals. The signal processing performed in the wireless vibration transmitter can be threshold judgment, time-domain signal compression, and frequency-domain signal fast Fourier transform (FFT). ) analysis, etc.

The threshold judgment is specifically: if the magnitude of the temperature, voltage, current signal and the amplitude of the frequency component of the vibration signal are greater than the threshold set by the host computer, a local alarm will be issued, and the alarm information will be uploaded to the host computer;

The time-domain signal compression is specifically: using wavelet transform to compress the time-domain data of the vibration acceleration signal that needs to be transmitted to the host computer, reducing the number of bytes that need to be transmitted through the industrial wireless network, and using the corresponding decompression algorithm on the host computer to restore Time domain vibration acceleration data.

The fast Fourier transform (FFT) analysis of the vibration acceleration signal is specifically: perform FFT transformation on the collected vibration acceleration signal to obtain the frequency spectrum of the vibration acceleration signal, and calculate the specified frequency component (such as : 0.5 multiplication, 1 multiplication, 2 multiplication, 3 multiplication, 4 multiplication, 5 multiplication, etc.) the size of the amplitude.

Figure 4 is a working flow chart of the wireless transmitter. Wireless vibration transmitters are generally powered by batteries. In order to reduce power consumption and improve battery life, the transmitter is equipped with a power management function. The transmitter starts the transmitter to complete data collection and analysis according to the set refresh cycle. , data transmission and other processing tasks. In the initialization 72, the startup program is loaded, the configuration parameters are loaded, and the current operating instructions are identified. The wireless transmitter starts working 71. Power on each module of the wireless transmitter hardware. After the initialization 72 is completed, enter the data acquisition 73. The data acquisition process includes operations such as A/D conversion, digital filtering, and data calibration; data calibration is based on the modulus The magnitude of the vibration signal is obtained from the digital quantity converted by the converter ADC and the voltage resolution of the ADC and the resolution of the vibration sensor. Then enter the next step 74 for data processing and local threshold judgment stage. Data processing includes time domain signal analysis and frequency domain signal analysis, data compression processing, reducing the amount of wireless network data transmission, improving battery life, and performing simple threshold comparison locally on the meter. , including voltage, current, temperature, and vibration thresholds. If it exceeds the limit, a local alarm 75 will be issued, and the equipment maintenance personnel will be notified through the alarm sound. Then the wireless vibration transmitter starts the wireless transceiver module, starts to connect to the wireless network 76, starts data transmission 77 after network connection, and transmits voltage, current, temperature time domain data, vibration signal analysis result data and compressed vibration acceleration signal time domain data , the wireless transmitter ends a working cycle 78, and waits for the start of the next working cycle; perform advanced fault diagnosis analysis in the factory-level fault diagnosis center and remote fault diagnosis center. Among them: the vibration signal analysis data is the magnitude of the specified frequency component in the vibration intensity and vibration acceleration signal spectrum. The specified frequency is the frequency set by the host computer according to the speed of the monitored object and the type of fault to be diagnosed.

Figure 5 is a flowchart of the fault diagnosis center. After entering the fault diagnosis process 81, the data from the on-site vibration transmitter first enters the factory-level fault diagnosis 82, and if the difficult and miscellaneous diseases that cannot be handled in the factory-level fault diagnosis center are sent to the remote fault diagnosis expert service center through the Internet. In the remote fault diagnosis 83, experts in the field conduct consultations according to the fault performance, and return the diagnosis results to the factory-level fault diagnosis center. If a fault or potential fault is found after the diagnosis, it enters the fault alarm 84 and notifies the equipment maintenance personnel 85 to notify relevant personnel. Equipment maintenance personnel; end this fault diagnosis 86.

The plant-level fault diagnosis center is specifically a diagnosis database containing result data, equipment parameters, result history data, thresholds and fault types; the result data is input into the fault diagnosis database, and through the result data, device parameters, and result history data in the fault diagnosis database , threshold and fault type to get the fault diagnosis result. Thresholds include voltage, current, temperature, vibration intensity, and thresholds of specified frequency components in the vibration acceleration spectrum. The maintenance information corresponding to the diagnosis result is also stored in the diagnosis database, which is used to assist the equipment maintenance personnel to realize equipment maintenance, and is sent to the equipment maintenance personnel along with the alarm information.

The diagnosis of the diagnostic database is realized through the operation status of the equipment and experience. For example: if there are high-order harmonics such as double frequency and triple frequency in the frequency spectrum of the vibration signal, the vibration is unstable; if the vibration direction is radial or axial, the fault type Transverse cracks appear on the motor shaft; if the frequency spectrum of the vibration signal appears 0.5 times the frequency, the vibration is stable, and the vibration direction is axial, the fault type is oil film whirl; if the frequency spectrum of the vibration signal appears 2 times the frequency, the frequency separation amplitude varies with the speed increases, the fault type is misalignment.

Claims (9)

1. A kind of equipment fault pre-maintenance method based on industrial wireless technology, it is characterized in that, by the data communication of industrial wireless network and industrial ethernet, field equipment is carried out real-time monitoring and fault pre-maintenance; comprise the following steps: The upper computer configures the parameters of the instruments used to monitor the equipment on site through the industrial Ethernet and industrial wireless network; the instrument collects the sensor information of the field devices according to the parameter configuration, and the result data after local processing of the sensor information is passed through the industrial wireless network, Industrial Ethernet is uploaded to the host computer; The upper computer performs fault diagnosis based on the result data, and judges the operating status of the equipment; if the type of fault is obtained, the on-site maintenance personnel are notified through the fault alarm to repair the equipment. 2. A method for equipment failure pre-maintenance based on industrial wireless technology according to claim 1, characterized in that: said equipment includes motors, fans, pumps, and compressors. 3. A device failure pre-maintenance method based on industrial wireless technology according to claim 1, characterized in that: the parameter configuration includes sampling frequency, refresh cycle, threshold, instrument working mode, data collection time, sensor channel number . 4. A method for equipment failure pre-maintenance based on industrial wireless technology according to claim 1, wherein the sensor information includes voltage, current, temperature, and vibration information. 5. A method of equipment failure pre-maintenance based on industrial wireless technology according to claim 1, characterized in that: in the local processing, performing local processing on the vibration sensor information includes: The vibration acceleration data collected by the vibration sensor is obtained through an integral operation to obtain the vibration velocity data, and the vibration intensity is obtained according to the vibration velocity data; Fast Fourier transform is performed on the vibration acceleration data collected by the vibration sensor to obtain the frequency spectrum of the vibration acceleration, and the amplitude of the specified frequency component is obtained according to the frequency spectrum; The vibration acceleration data collected by the vibration sensor is compressed to obtain compressed data. 6. A method of equipment failure pre-maintenance based on industrial wireless technology according to claim 1, characterized in that: said result data includes voltage, current, temperature data, vibration intensity, amplitude of specified frequency components, compression data. 7. A method for equipment failure pre-maintenance based on industrial wireless technology according to claim 1, characterized in that: the host computer performs failure diagnosis according to the result data, and judging the operation status of the equipment includes the following steps: input the result data to Fault diagnosis database, through the result data, equipment parameters, result history data, threshold and fault type in the fault diagnosis database to obtain the fault diagnosis result of the fault type. 8 . The method for equipment failure pre-maintenance based on industrial wireless technology according to claim 7 , wherein the thresholds include thresholds of voltage, current, temperature data, vibration intensity, and amplitude of specified frequency components. 9. A kind of equipment failure pre-maintenance method based on industrial wireless technology according to claim 1, characterized in that: said failure alarm can also send alarm information and maintenance information in the form of mobile phone information through local sound and light alarm or 3G network It is recommended to send to the field equipment maintenance personnel.