A method for remotely diagnosing oil leaks in the hydraulic oil system of a hydro-generator.

Abstract

This invention discloses a method for remotely diagnosing oil leaks in the hydraulic oil system of a hydro-generator. Each oil tank in the hydraulic oil system using this method has a simulated quantity for monitoring liquid level changes. There can be one or more oil tanks, and their shape is not limited. The simulated liquid level data from the oil tanks is uploaded to an industrial internet platform to calculate and monitor the total oil volume of the system. The trend of the total oil volume change is used to determine whether an oil leak has occurred. Utilizing the data analysis tools of the industrial internet platform, a three-dimensional model involving the total oil volume is established. Characteristic values ​​and gradual change rates of the total oil volume change are extracted, and threshold limits are set for changes in the total oil volume operating data, characteristic value data, and gradual change rate data. Exceeding these limits triggers an early warning, thereby enabling the monitoring and leak diagnosis function for oil systems with one or more oil tanks. Therefore, this method is suitable for widespread application.

Description

Technical Field

[0001] This invention belongs to the field of hydraulic oil monitoring and leakage diagnosis technology, specifically, it relates to a method for remotely diagnosing oil leakage in the hydraulic oil system of a hydro-generator. Background Technology

[0002] The total volume of hydraulic oil in a hydraulic oil system is the sum of the volumes of several parts. Considering the incompressibility of hydraulic oil, the change in volume due to pressure is negligible and is therefore ignored in this study. Due to the thermal expansion and contraction of turbine oil, the volume of the pressurized oil also changes with temperature. However, since the density of the L-TSA46 turbine oil used in the pressurized oil system changes very little at different temperatures, the corresponding volume change is also small and is also ignored in this study. In hydropower plants, due to the long pipelines and numerous valves and joints, a failure in any link or component can frequently lead to oil spraying and leakage, causing significant turbine oil leakage and affecting the generator set's standby time.

[0003] Based on research into the multi-tank oil system of a hydropower station, a widely applicable intelligent method for monitoring oil leaks has been developed. For example, in the governor system of the Miaowei Hydropower Station, the oil is divided into three parts: oil in the return tank, oil in the pressure tank, and oil in a fixed volume within the pipeline. The following problems exist:

[0004] (1) The oil levels in the return oil tank and pressure oil tank are constantly changing, rising and falling, and are unstable, making it impossible to directly determine whether there is an oil leak through remote monitoring. (2) The power station is unmanned and the inspection cycle is long. If the governor system leaks oil, it is difficult to find the leak point or water ingress point in time, and it is even more impossible to diagnose and warn in advance based on the monitoring of oil leaks. Summary of the Invention

[0005] The purpose of this invention is to provide a method for remotely diagnosing oil leaks in the hydraulic oil system of a hydro-generator. This method monitors oil leaks in the multi-tank oil system of the Miaowei Hydropower Station and diagnoses and warns of leaks in their early stages, providing a powerful on-site oil leak monitoring capability for unmanned or minimally staffed operations.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A method for remotely diagnosing oil leaks in the hydraulic oil system of a hydro-generator includes the following steps:

[0008] S1, acquire the analog quantity of the change in oil level in each tank of the hydraulic oil system;

[0009] S2, upload the acquired analog data of the oil tank level change to the industrial internet platform;

[0010] S3 utilizes an industrial internet platform to calculate the total oil volume of the hydraulic oil system, establishes a three-dimensional model of the total oil volume of the hydraulic oil system for calculation, and extracts the characteristic value and gradual change rate of the total oil volume from the three-dimensional model that is stable over a long period of time.

[0011] S4 uses the industrial internet platform to set alarm thresholds for the real-time value, characteristic value, and slow change rate of total oil volume.

[0012] S5. Compare the real-time value, characteristic value, and gradual change rate of the total oil volume obtained in step S3 with the alarm threshold in step S4, thereby making a prediction and alarm for oil leakage faults in the hydraulic oil system.

[0013] Furthermore, in this invention, it is applicable to hydraulic oil systems having one or more oil reservoirs, each oil reservoir having a level gauge for monitoring changes in the oil level.

[0014] Furthermore, in this invention, the total oil volume of the hydraulic oil system is obtained by comprehensively calculating the changes in the liquid level of one or more oil tanks, which is used for monitoring and diagnosing oil leaks.

[0015] Furthermore, in this invention, the industrial internet platform predicts the number of days until the current rate of gradual change reaches the alarm threshold based on the current rate of gradual change, thereby achieving early warning of the degradation level.

[0016] Furthermore, in this invention, the three-dimensional model is generated by the total oil volume V of the multi-tank system. 总 As an intermediate quantity, it is composed of the unit head ΔH and the unit active power P.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] The remote diagnostic method of this invention can monitor oil leakage in hydraulic oil systems in a timely manner and provide oil leakage warnings; it can effectively reduce the inspection cycle, and under normal circumstances, there is no need to check the oil leakage of systems such as speed governors on site. Only after receiving an oil leakage warning can the speed governor system be checked on site; based on the principle of model building, this method of building a multi-tank oil leakage diagnostic model is applicable to single-tank oil leakage diagnostic model scenarios and has a wide range of applications. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the multi-tank diagnostic model architecture in an embodiment of the present invention.

[0020] Figure 2 This is a curve showing the change in the total oil quantity parameter of the governor control oil system in a hydroelectric power plant in an embodiment of the present invention. Detailed Implementation

[0021] The present invention will be further described below with reference to the accompanying drawings and embodiments. The embodiments of the present invention include, but are not limited to, the following embodiments.

[0022] Example

[0023] This invention discloses a method for remotely diagnosing oil leakage in the hydraulic oil system of a hydro-generator, comprising the following steps:

[0024] S1, acquire the analog quantity of the change in oil level in each tank of the hydraulic oil system;

[0025] S2, upload the acquired analog data of the oil tank level change to the industrial internet platform;

[0026] S3 utilizes an industrial internet platform to calculate the total oil volume of the hydraulic oil system, establishes a three-dimensional model of the total oil volume of the hydraulic oil system for calculation, and extracts the characteristic value and gradual change rate of the total oil volume from the three-dimensional model that is stable over a long period of time.

[0027] S4 uses the industrial internet platform to set alarm thresholds for the real-time value, characteristic value, and slow change rate of total oil volume.

[0028] S5. Compare the real-time value, characteristic value, and gradual change rate of the total oil volume obtained in step S3 with the alarm threshold in step S4, thereby making a prediction and alarm for oil leakage faults in the hydraulic oil system.

[0029] In practice, firstly, a multi-tank oil leak diagnosis model is established, and the total oil volume V is calculated. 总 (unit: m) 3 () as an intermediate quantity. For the total oil volume V 总 Set a threshold alarm limit; an alarm will be triggered if the change exceeds the threshold limit. Calculate the total fuel volume V. 总 The method is as follows: multiply the multiple oil levels of the multiple oil tanks by their respective different bottom areas, and then add them together to generate the total oil volume V of the multi-tank system. 总 (unit: m) 3 As an intermediate quantity, it is used in conjunction with the unit head ΔH (in mm) and the unit active power P (in MW) to form a three-dimensional model. Based on the data from this dynamic three-dimensional model, characteristic values ​​with a stable time exceeding 36,000 seconds are sought, and the total oil volume V of the multi-tank system is calculated. 总 The real-time data is compared with the generated feature values. In this process, invalid data with measurement point jumps are eliminated. The total oil volume V of the multi-tank system is comprehensively evaluated in combination with the unit's operating status. 总 Changes in the total fuel volume V of the multi-tank system. 总Data change is represented by ΔV as the rate of gradual change, which characterizes the change in a characteristic value over a fixed period. The industrial internet platform predicts the number of days until the rate of gradual change reaches the characteristic value threshold based on the current rate of gradual change, thus providing a deterioration warning. A severe warning is issued if the characteristic target value is expected to be reached within the next 10 days, and a general warning is issued if it is expected to be reached within the next 30 days. Based on the actual calculation data of each unit model, the total oil volume V of the multi-tank system is observed and analyzed over a certain period. 总 Real-time values ​​and characteristic values ​​are used, and general and severe warning thresholds are appropriately set to ultimately perform intelligent diagnosis of whether oil-related system equipment is leaking. Overall architecture reference. Figure 1 .

[0030] Taking a leak diagnosis model of the governor control oil system applied in a hydroelectric power plant as a typical example, further application case analysis is conducted. The oil in the governor control oil system is mainly located in two parts: the return oil tank and the pressure oil tank. Based on the geometric dimensions of the governor's pressure oil tank and return oil tank, and their oil levels, the turbine oil volume in the pressure oil tank and return oil tank is calculated respectively. The sum of the two is the total oil volume of the entire governor system. Using an industrial internet platform, a three-dimensional model of the total oil volume of the governor system is established. For a relatively stable three-dimensional model over a long period, characteristic values ​​and gradual change rates of the total oil volume are extracted. Appropriate alarm thresholds are set for the real-time value, characteristic value, and gradual change rate of the total oil volume, thereby enabling the prediction and alarm of oil leakage faults in the governor system.

[0031] (1) Data source: ① Governor return oil tank level h1; ② Governor pressure oil tank level h2; This data is taken from the computer monitoring system.

[0032] (2) Model Construction. The governor's pressure oil tank is cylindrical in the middle, and the bottom of the governor's pressure oil tank has a fixed oil volume, approximately hemispherical with a radius of 0.8m; the governor's return oil tank is cubic with a base area of ​​4m × 2.25m. Based on the above data, the total oil volume V of the governor system is... 总 The calculation formula is as follows:

[0033] V 总 =V 回油箱 +V 压力油罐 +V 固定油量

[0034] = (h1×4×2.25)+(h2×3.14×0.8×0.8)+2×3.14×0.8×0.8×0.8÷3

[0035] = 9h1 + 2.0096h2 + 1.0718(m) 3 )

[0036] (3) The total oil volume is calculated using the "Governor Pressure Oil Volume" algorithm of the Industrial Internet algorithm platform, and a three-dimensional model is established by combining the governor return oil tank level and the pressure oil tank level.

[0037]

[0038] (4) Output results. The model outputs are as follows: real-time operating data, characteristic values, and gradual change rate of the total oil volume of the governor system.

[0039] Practical verification showed that the industrial internet system at a hydroelectric power plant operated well after configuring this model. Using this method, an abnormal oil leak in the governor system was promptly detected: On January 8, 2022, staff using the industrial internet platform discovered a decreasing trend in the total oil level of the governor for Unit 1. Upon inspection, a significant oil leak was found in the mechanical overspeed oil supply valve of Unit 1, posing a potential risk of unplanned unit shutdown. That evening, the hydroelectric power plant's mechanical professionals took advantage of a low-load period to shut down the unit and address the defect, after which the oil leak was resolved. Figure 2 This is the curve showing the change in total oil volume parameters of the power plant's governor system. Based on the application effect of industrial internet intelligent monitoring and oil leak diagnosis technology in power plants, it undoubtedly provides a way to predict whether equipment oil leaks will worsen. Production personnel can promptly detect early signs of equipment oil leaks, eliminate potential hazards, ensure long-term stable operation of equipment, avoid unplanned shutdowns, and provide strong technical support for the unmanned operation mode of hydropower plants.

[0040] The above embodiments are merely one of the preferred embodiments of the present invention and should not be used to limit the scope of protection of the present invention. Any modifications or refinements made to the main design concept and spirit of the present invention that are not of substantial significance, but solve the same technical problem as the present invention, should be included within the scope of protection of the present invention.

Claims

1. A method of remotely diagnosing hydraulic oil system leaks in a hydroelectric generator, the method comprising: Comprise the following steps: S1, obtain the analog quantity of each tank level change of the hydraulic oil system; S2, upload the obtained analog quantity data of the tank level change to the industrial internet platform; S3, calculating the total oil quantity of the hydraulic oil system by using the industrial internet platform, establishing a three-dimensional model of the total oil quantity of the hydraulic oil system participating in operation, and taking the characteristic value and the slow variation rate of the total oil quantity of the three-dimensional model stable for a long time; wherein the three-dimensional model is generated by generating the total oil quantity V 总 As an intermediate quantity, together with the unit water head ΔH and the unit active power P S4, set alarm thresholds for the real-time value, characteristic value and slow change rate of the total oil quantity respectively by using the industrial internet platform; S5, compare the real-time value, characteristic value and slow change rate of the total oil quantity calculated in step S3 with the alarm thresholds in step S4, and thus make oil leakage fault prediction and alarm of the hydraulic oil system.

2. The method for diagnosing a hydraulic oil system of a hydraulic generator according to claim 1, wherein It is suitable for hydraulic oil systems with single or multiple oil storage tanks, and each oil storage tank has a liquid level meter that can monitor the change of the oil tank level.

3. The method of claim 2, wherein the method further comprises: Through comprehensive calculation of the change of single or multiple oil tank levels, the total oil quantity of the hydraulic oil system is obtained for monitoring and diagnosing oil leakage.

4. The method for diagnosing a hydraulic oil system of a hydraulic generator according to claim 3, wherein The industrial internet platform predicts the number of days for the slow change rate to reach the alarm threshold according to the current slow change rate, and realizes the early warning of the deterioration level.

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