CN-121978170-A - Online monitoring system and method for grease metal particles of main bearing of wind driven generator

CN121978170ACN 121978170 ACN121978170 ACN 121978170ACN-121978170-A

Abstract

The invention discloses an online monitoring system and an online monitoring method for grease metal particles of a main bearing of a wind driven generator, and relates to the technical field of wind power generation monitoring, wherein the online monitoring system comprises a grease guide mechanism, a grease sampling box, a heating mechanism, an online monitoring device, a waste oil tank, a real-time signal processing module, a data analysis processing module and a man-machine interaction terminal, wherein the grease guide mechanism is arranged beside a partition board low point between a bearing seat of the main bearing and an oil return cavity; the on-line monitoring device is connected to the downstream of the grease sampling box, detects the content of magnetic metal particles in the grease based on an inductance principle, uploads an acquired signal to the real-time signal processing module, uploads the processed signal to the data analysis processing module for analysis and processing, evaluates the health state of the bearing and displays the health state through the man-machine interaction terminal, and solves the problem that on-line monitoring of the magnetic metal particles in the grease in the main bearing of the wind driven generator is difficult in the prior art.

Inventors

ZHENG FULONG
YANG CHENGTAO
WANG FENGJUN
ZOU YINGDONG
YE FEIYANG
CHANG WENJUAN
FENG HAIBING
YE ZHIWEI
DUAN ZHIQIANG
LIANG ZHENGJUN

Assignees

东方电气集团东方电机有限公司

Dates

Publication Date: 20260505
Application Date: 20260202

Claims (10)

1. The on-line monitoring system for the grease metal particles of the main bearing of the wind driven generator is characterized by comprising a grease guide mechanism (1), a grease sampling box (2), a heating mechanism (3), an on-line monitoring device (4), a waste oil box (5), a real-time signal processing module, a data analysis processing module and a man-machine interaction terminal, wherein a valve is arranged on a channel connected with the grease sampling box (2) by the grease guide mechanism (1); The grease guide mechanism (1) is arranged at the low point of a partition plate (12) between a bearing seat (9) of the main bearing (7) and the oil return cavity (10) and is used for leading out grease passing through a bearing raceway to enter the grease sampling box (2); the heating mechanism (3) is used for heating the lubricating grease in the grease sampling box (2) so as to reduce the viscosity of the lubricating grease; the waste oil box (5) is used for recycling the detected waste lubricating grease; The online monitoring device (4) is connected to the downstream of the grease sampling box (2), detects the content of magnetic metal particles in the lubricating grease based on an inductance principle, and uploads the collected signals to the real-time signal processing module; And the real-time signal processing module uploads the processed signals to the data analysis processing module for analysis and processing, and the health state of the bearing is estimated and displayed through the man-machine interaction terminal.
2. The system according to claim 1, wherein the heating mechanism (3) is mounted and fixed at the bottom of the grease sampling cartridge (2).
3. The system according to claim 1, wherein a millimeter-sized filter screen (1.1) is arranged in the grease guide mechanism (1), the lower part of the filter screen (1.1) is connected with a conical guide groove (1.2), the diameter of a lower pipeline is more than or equal to 30mm, and a valve and a flow sensor I (1.3) which are matched with high-viscosity grease are arranged on the pipeline; The pipeline of the oil guiding mechanism (1) penetrates through the cover plate I (13) of the oil return cavity (10), one end of the pipeline is connected with the bearing seat (9) through a bolt, the other end of the pipeline is connected with the oil sampling box (2) through a flange, the interfaces at the two ends of the pipeline are respectively provided with a heat insulation layer and a damping rubber pad, and a plane sealing glue layer is smeared between gaps of the cover plate I (13).
4. The system according to claim 1, wherein the grease sampling box (2) is provided with an exhaust valve I (2.1) at the upper part and a valve at the lower part, a temperature sensor (2.2) is assembled in the grease sampling box, the temperature sensor (2.2) is connected with a heating mechanism (3) in a signal manner, and the heating mechanism (3) is controlled to start and stop through a temperature threshold value, so that the viscosity of grease is reduced to a preset fluidity requirement.
5. The system according to claim 2, wherein the heating mechanism (3) comprises a box (3.1), an electric heater (3.2) and a support frame (3.3); The box body (3.1) is welded or combined with the lower part of the grease sampling box (2), the electric heater (3.2) is fixed on the box body (3.1) through the supporting frame (3.3), the electric heater (3.2) adopts a heating pipe (3.4) with an annular double-layer structure and is sleeved with a radiating fin, the rated power is 100W-2000W, and the heating pipe (3.4) and the radiating fin are placed in high-boiling-point heat conduction oil; The upper part of the heating mechanism (3) is provided with an exhaust valve II (3.5) for maintaining the internal pressure balance in a cold state and a hot state.
6. The system according to claim 1, wherein the on-line monitoring device (4) comprises a coil (4.1), a supporting frame (4.2), a heat conducting glue (4.3), a flow sensor II (4.4), a grease tube (4.5), a housing (4.6) and a housing cover plate (4.7); The coil (4.1) is wound by polyimide or polyester film rectangular electromagnetic wire, and insulating heat-conducting glue (4.3) is filled between the coil (4.1) and the shell (4.6); The shell (4.6) and the shell cover plate (4.7) are made of copper sleeves, aluminum alloy or steel plate materials, and the gap between the shell and the coil (4.1) is not smaller than 2 times of the diameter of the oil pipe (4.5); the grease pipe (4.5) is made of polytetrafluoroethylene or alumina ceramic material; the flow sensor II (4.4) is arranged on the grease pipe (4.5) and is used for monitoring whether grease enters the monitoring equipment and whether grease in the grease sampling box (2) is emptied; And the coil (4.1) is electrified with high-frequency alternating current of 50-1000 Hz, and the current change quantity caused by the magnetic flux change is detected through the current detection module, so that the real-time content of the magnetic metal particles is calculated.
7. The system according to claim 1, characterized in that the waste oil tank (5) is provided with a liquid level sensor (5.1) for monitoring the waste grease liquid level; the real-time signal processing module is used for filtering the detection signal and removing abnormal values; The data analysis processing module is used for accessing the data processed by the real-time signal processing module into a main control system and a centralized control system for storage analysis, and automatically sending a grease injection strategy adjustment instruction to an automatic lubrication system executing mechanism when grease abnormality is detected.
8. The on-line monitoring method for the grease metal particles of the main bearing of the wind driven generator is characterized by comprising the following steps of: S1, grease flowing through a bearing raceway is led out through a grease guiding mechanism (1) which is arranged beside a low point of a partition plate (12) between a bearing seat (9) of a main bearing (7) and an oil return cavity (10), a millimeter-level filter screen (1.1) and a conical guide groove (1.2) are arranged in the grease guiding mechanism (1), and the diameter of a lower pipeline is more than or equal to 30mm; S2, opening a valve between the grease guide mechanism (1) and the grease sampling box (2), and closing the valve after the flow sensor I (1.3) detects that the grease amount reaches a preset value so as to enable grease to be reserved in the grease sampling box (2); S3, starting a heating mechanism (3) at the bottom of the grease sampling box (2), heating grease in the box body (3.1), monitoring the temperature of the grease in real time by using a temperature sensor (2.2), and closing the heating mechanism (3) when the temperature reaches a preset threshold value and the viscosity of the grease is reduced to a preset fluidity requirement; S4, opening a valve at the lower part of the grease sampling box (2), starting the online monitoring device (4) when a flow sensor II (4.4) of the online monitoring device (4) detects that the flow of the lubricating grease meets the detection requirement, generating a magnetic field through a coil (4.1) which is electrified with high-frequency alternating current of 50-1000 Hz, detecting the current variation of the coil (4.1) caused by magnetic metal particles, and calculating the real-time content of the magnetic metal particles; S5, filtering the detection signal through a real-time signal processing module, removing abnormal values, and after the detection signal is stored and analyzed through a data analysis processing module, evaluating the health state of the main bearing (7) and displaying the health state through a man-machine interaction terminal.
9. The method of claim 8, wherein when the abnormal content of the magnetic metal particles in the grease is detected in the step S5, an instruction is issued to an execution mechanism of the automatic lubrication system to adjust the grease injection period and the grease injection amount, and the detected waste grease is discharged into a waste oil tank (5) for recovery.
10. The method of claim 8, wherein in the step S1, the pipeline of the oil guiding mechanism (1) passes through a cover plate I (13) of the oil return cavity (10), a heat insulation layer and a damping rubber pad are arranged at the joint of two ends of the pipeline, and a plane sealant is smeared on a gap of the cover plate I (13).

Description

Online monitoring system and method for grease metal particles of main bearing of wind driven generator Technical Field The invention relates to the technical field of wind power generation monitoring, in particular to an online monitoring system and method for grease metal particles of a main bearing of a wind power generator. Background In the field of wind power generation, large-scale wind power generators generally adopt a horizontal arrangement structure, and can be divided into three types of low-speed direct drive type, medium-speed semi-direct drive type and high-speed type according to transmission types. No matter what transmission type is adopted, the wind driven generator is provided with a mechanical transmission chain system (short for shafting) consisting of a main shaft and a bearing seat, and a main bearing is arranged between the main shaft and the bearing seat to bear the load of the whole wind driven generator. Because the wind wheel of the wind driven generator has low rotating speed and large bearing wind load, the main bearing usually adopts a large-scale grease lubrication rolling bearing, and common forms comprise a double-row cone bearing, a single-row cone bearing, a three-row column bearing and the like. The main bearing is used as a key component of the wind driven generator, and the running state of the main bearing directly determines the safe and stable running of the wind driven generator. Once the main bearing is abnormal, fault or failure, the main bearing must be subjected to the maintenance treatment, the treatment process is high in cost, the cost is usually several times of the value of the main bearing and even is equivalent to the value of the whole fan, if the main bearing is not treated in time, the main bearing is seriously worn or even broken, the whole fan is blocked, the whole fan is overturned in an extreme case, and the economic loss and the safety effect are further amplified. Because the main bearing is in a closed running state, the real-time running state of each component in the main bearing cannot be intuitively observed, and therefore the running state of the main bearing needs to be monitored and estimated through an indirect means. The analysis of the characteristics of the lubricating grease is one of the most commonly used monitoring means at present, and the performance (such as water content, solid particle content and the like) of the main bearing lubricating grease of the wind driven generator has a decisive influence on the service life and reliability of the bearing. In the running process of the unit, the main bearing is inevitably worn, and because the bearing is made of special rolling bearing steel, metal particles generated by wear are mainly ferromagnetic iron particles, and the iron particles are wrapped and mixed by lubricating grease. In the running-in period of the initial operation stage of the bearing, a small amount of iron particles generally do not have great influence on the performance of the bearing, and fresh grease which can be injected through an automatic grease injection system is discharged along with a lubricating oil path, but when abnormal wear occurs in the bearing due to abnormal operation, the content of the iron particles in the lubricating grease can gradually rise, so that the lubricating performance of the lubricating grease can be deteriorated, the wear of the bearing can be further aggravated, and finally the main bearing can possibly fail. Conversely, when the content of iron particles in the lubricating grease is abnormal (especially the trend of change is abnormal), the main bearing is often predicted to have potential fault hazards and even impending failure. Therefore, the running state of the main bearing can be effectively estimated by monitoring the content of iron particles and the change trend in the lubricating grease, and a basis is provided for state estimation and fault diagnosis of the bearing. The lubricating grease for the wind driven generator mainly comprises base oil, a thickening agent and a limit additive, and has the working characteristics that the base oil is separated out from the thickening agent to form an oil film when the bearing is in operation, and the base oil is absorbed by the thickening agent again when the bearing stops operating. The viscosity of the base oil determines the thickness of an oil film, the larger the viscosity is, the thicker the oil film is, the penetration of the thickening agent influences the flowability of lubricating grease, and the higher the penetration is, the better the flowability is. In the wind power field, in order to meet the requirements of effective discharge and leakage prevention of lubricating grease, the lubricating grease with the penetration of 0.1mm at normal temperature of 305-340 is generally selected. From the viewpoint of monitoring convenience, the grease is required to have good fluidity to smoothly enter the monitoring equip