Method for identifying degradation trend of rotary drive electromechanical device

Abstract

The application discloses a kind of rotary drive class electromechanical equipment degradation trend identification method, belong to electromechanical equipment degradation identification technical field, the present application is based on vibration, temperature and current multi-source synchronous data, constructs mechanical state, thermal state and electrical state between degradation propagation relationship, and combines actual operation state dynamic correction degradation propagation benchmark, whether equipment exists degradation propagation acceleration trend by the deviation degree of degradation propagation rate is judged.The present application can realize the data correlation between mechanical, electrical and thermal state, and then can accurately describe the cumulative and transmission characteristics of degradation process under the action of multi-physical field, effectively improve the accuracy of rotary drive class electromechanical equipment degradation trend identification.

Description

Technical Field

[0001] This invention relates to the field of electromechanical equipment degradation identification, and in particular to a method for identifying degradation trends in rotary drive electromechanical equipment. Background Technology

[0002] Rotary drive electromechanical equipment such as motors, fans, pumps, and compressors are important power execution units in industrial systems, and their operating status directly affects the equipment's continuous operation capability and safety reliability.

[0003] During long-term operation, the internal mechanical structure, electrical components, and heat conduction components of the equipment are subjected to continuous effects of vibration, shock, changes in electrical load, and temperature changes, which gradually lead to degradation phenomena such as wear, fatigue, insulation aging, and performance decline.

[0004] In daily practice, the existing technical solutions have been found to have the following problems: Existing methods for condition monitoring of rotary-driven electromechanical equipment typically collect operating parameters such as vibration, temperature, and current, and conduct condition evaluation through single-parameter analysis or multi-parameter fusion. However, the equipment degradation process is affected by the interaction between mechanical, electrical, and thermal states. Existing methods are insufficient to fully reflect the interaction relationships between different physical state parameters over time, and cannot accurately describe the accumulation and transmission characteristics of the degradation process under the action of multiple physical fields.

[0005] In addition, existing degradation trend identification methods are mostly based on fixed state benchmarks or preset thresholds, which do not fully consider the impact of load changes and thermal environment changes on the degradation evolution rate during actual equipment operation, resulting in insufficient accuracy in degradation trend identification under variable operating conditions.

[0006] Therefore, it is necessary to provide a new technical solution to solve the above problems. Summary of the Invention

[0007] To address the aforementioned technical problems, this application provides a method for determining the degradation trend of rotary-driven electromechanical equipment. This method can construct the degradation propagation relationship between mechanical, thermal, and electrical states based on multi-source synchronous data of vibration, temperature, and current, and dynamically correct the degradation propagation benchmark in conjunction with the actual operating conditions, thereby improving the accuracy of determining the degradation trend of rotary-driven electromechanical equipment.

[0008] A method for determining the degradation trend of rotary-driven electromechanical equipment includes: S1. Simultaneously acquire vibration acceleration signals, temperature signals, and current signals using the same clock reference; S2. Establish vibration reference quantities, temperature reference quantities, and current reference quantities based on the thermal balance state of the equipment; S3. Construct the cumulative vibration response, cumulative vibration trend, cumulative temperature change, absolute temperature exposure, and cumulative current change, respectively. S4. Construct vibration response characterization quantities, thermal response characterization quantities, and electrothermal effect characterization quantities, and establish the temporal correlation between mechanical state, thermal state, and electrothermal effect state. S5. Degradation propagation response factors are constructed based on vibration response characterization, thermal response characterization, and electrothermal effect characterization, and further degradation propagation evolution quantity and degradation propagation rate are formed. S6. Obtain the degradation propagation reference rate from the calibration data under the standard operating conditions of the equipment, and dynamically correct the degradation propagation reference rate in combination with the electrothermal effect state during operation to form a normalized degradation propagation rate offset. S7. Determine whether the equipment has an accelerating trend of degradation propagation based on the degree of deviation in the degradation propagation rate.

[0009] Preferably, step S2 includes: S21. Determine whether the equipment has reached thermal equilibrium based on the temperature signal; S22. Establish a calibration interval by taking the moment when the equipment reaches thermal equilibrium as the calibration start moment; S23. Determine the number of calibration sampling points based on the calibration interval length and sampling time interval; S24. Calculate the vibration reference quantity, temperature reference quantity, and current reference quantity.

[0010] Preferably, step S21 includes: When the sum of the number of sampling points in the temperature determination time window and the number of sampling points in the heat balance determination window is greater than the preset threshold, the heat balance state determination is started. When the average temperature change rate within the thermal balance determination window is less than a preset threshold, the determination device enters a thermal balance state. The formula for calculating the average temperature change rate within the thermal equilibrium determination window is: ; In the formula, The average rate of temperature change within the thermal equilibrium determination window. This indicates the number of sampling points within the thermal balance determination window. express The average rate of temperature change at any given time.

[0011] Preferably, in step S24, the vibration reference quantity is the root mean square value of the vibration acceleration sequence of the equipment under thermal equilibrium state, and its calculation formula is: ; The temperature reference quantity is the average value of the temperature sampling sequence of the equipment under thermal equilibrium conditions, and its calculation formula is: ; The current reference quantity is the root mean square value of the current sampling sequence of the equipment under thermal equilibrium conditions, and its calculation formula is: ; In the formula, Indicates the vibration reference quantity; Indicates a temperature reference quantity; Indicates a current reference quantity; Indicates the number of sampling points during the calibration phase; This represents the nth discrete sampling time within the calibration interval.

[0012] Preferably, step S3 includes: Based on vibration acceleration and vibration reference quantities, construct the cumulative quantity of vibration response and the cumulative quantity of vibration change trend; Based on temperature and temperature baseline, construct the cumulative temperature change and absolute temperature exposure; Based on current and current reference quantity, construct the cumulative current change quantity; The formula for calculating the cumulative vibration response is: ; In the formula, Indicates the time of data collection The cumulative amount of vibration response; Indicates the time of data collection The absolute value of vibration acceleration; Indicates the sampling time interval; The formula for calculating the cumulative amount of vibration change trend is: ; In the formula, Indicates the time of data collection The cumulative amount of vibration change trend; Indicates the time of data collection The amount of vibration change; The formula for calculating the cumulative temperature change is: ; In the formula, Indicates the time of data collection The cumulative amount of temperature change; The formula for calculating absolute temperature exposure is: ; In the formula, Indicates the time of data collection Absolute temperature exposure; The formula for calculating the cumulative change in current is: ; In the formula, Indicates the time of data collection The cumulative change in current.

[0013] Preferably, in step S4, the formula for calculating the vibration response characterization quantity is: ; In the formula, Indicates the time of data collection Vibration response characterization quantity; The formula for calculating the thermal response characterization quantity is: ; In the formula, Indicates the time of data collection Thermal response characterization quantity; The formula for calculating the characteristic quantity of electrothermal effect is: ; In the formula, Indicates the time of data collection The characteristic quantity of electrothermal effect; Collection time The cumulative change in current; Indicates the time of data collection The load-thermal coupling factor.

[0014] Preferably, in step S5, the formula for calculating the degradation propagation response factor is: ; In the formula, Indicates the time of data collection Degradation propagation response factor; Indicates the time of data collection The normalized vibration response characterization quantity; Indicates the time of data collection The normalized temperature response characterization quantity; Indicates the time of data collection Normalized electrothermal effect characterization quantity; Used to characterize the degree of correlation response when the mechanical vibration state response and the thermal state response are enhanced together within the same time window; This indicates the degree of correlation between the electrothermal action state and the thermal state response; Indicates the time of data collection The normalized change in vibration response; Indicates the time of data collection The normalized change in electrothermal effect.

[0015] Preferably, in step S6, the formula for calculating the degradation propagation evolution amount is: ; In the formula, Indicates the time of data collection The amount of degradation, propagation, and evolution.

[0016] Preferably, in step S6, the formula for calculating the normalized degradation propagation rate offset is: ; In the formula, Indicates the time of data collection Normalized degenerate propagation rate offset; Indicates the sampling time The rate of degradation propagation; Indicates the time of data collection The revised degradation propagation baseline rate; To represent extremely small positive numbers, avoid having a denominator of zero; The formula for calculating the degradation propagation rate is: ; The formula for calculating the modified degradation propagation baseline rate is: ; In the formula, Indicates the sampling time The amount of degradation, propagation, and evolution.

[0017] Preferably, step S7 includes: S71. Calculate the standard deviation of the normalized degradation propagation rate offset: ; In the formula, The standard deviation of the normalized degradation propagation rate offset; This represents the average value of the normalized degradation propagation rate offset. S72. Threshold for judging the degradation trend of computing equipment: ; In the formula, This indicates that the rate of equipment degradation propagation deviates from the threshold; S73. Compare the normalized degradation propagation rate offset with the equipment degradation trend discrimination threshold to determine whether the equipment has an accelerated degradation propagation trend.

[0018] Compared with the prior art, this application has at least the following beneficial effects: 1. This invention synchronously acquires vibration acceleration signals, temperature signals, and current signals using the same clock reference, and establishes vibration, temperature, and current reference quantities based on the equipment's thermal equilibrium state. This allows state data from different physical domains to form comparable state references on a unified time axis. Based on this, cumulative vibration response, cumulative vibration change trend, cumulative temperature change, absolute temperature exposure, and cumulative current change are constructed, respectively. This transforms instantaneous state changes during equipment operation into time-evolving state variables that characterize the cumulative degradation process, improving the ability to characterize the long-term degradation process of rotary-driven electromechanical equipment.

[0019] 2. This invention constructs vibration response, thermal response, and electrothermal effect characterization quantities, and establishes temporal correlations between mechanical, thermal, and electrothermal states, thereby quantifying the degradation propagation process between different physical processes within the equipment. Specifically, the cumulative vibration response and cumulative vibration change trend jointly describe the degradation evolution process of the mechanical structure; the cumulative temperature change and absolute temperature exposure jointly describe thermal cycling and long-term thermal exposure; and the cumulative current change and absolute temperature exposure establish a load-thermal correlation relationship. This avoids relying solely on changes in a single state parameter for degradation judgment, improving the accuracy of the degradation propagation state description.

[0020] 3. This invention constructs a degradation propagation response factor based on vibration response, thermal response, and electrothermal effect characteristics, and further forms a degradation propagation evolution quantity and a degradation propagation rate, thereby describing the dynamic propagation process between changes in mechanical state, thermal state, and electrothermal effects. A degradation propagation baseline rate is obtained through calibration data under standard operating conditions of the equipment, and this baseline rate is dynamically corrected by considering the electrothermal effect state during operation, forming a normalized degradation propagation rate offset. The degree of deviation in the degradation propagation rate is used to determine whether the equipment exhibits an accelerating trend of degradation propagation. Compared to state judgment methods based on fixed parameter thresholds, this invention can identify deviations in the degradation propagation process within the equipment from the normal evolution law, improving the stability of degradation trend identification under complex operating conditions. Attached Figure Description

[0021] The following sections will describe some specific embodiments of the invention in a detailed manner by way of example and not limitation, with reference to the accompanying drawings. The same reference numerals in the drawings denote the same or similar parts or portions. Those skilled in the art should understand that these drawings are not necessarily drawn to scale. In the drawings: Figure 1 This is a schematic diagram of the overall process of the present invention. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0023] like Figure 1 As shown, a method for determining the degradation trend of rotary-driven electromechanical equipment includes: S1. Simultaneously acquire vibration acceleration signals, temperature signals, and current signals using the same clock reference.

[0024] During the operation of rotary-driven electromechanical equipment, the mechanical structure is continuously subjected to the combined effects of vibration, shock, current fluctuations, and temperature changes. These multi-source physical effects accumulate over time and gradually lead to degradation phenomena such as increased wear of equipment components and decreased operating performance.

[0025] The rotary drive electromechanical equipment includes motor drive devices, fans, pumps and compressors.

[0026] To acquire multi-dimensional status information during equipment operation, corresponding types of sensors are deployed in different functional areas of the equipment to synchronously collect vibration acceleration signals, temperature signals, and current signals, as detailed below: Vibration acceleration sensors (such as piezoelectric acceleration sensors) are placed on the outer surface of the power output connection area or rotating component support structure of the equipment (such as the motor mounting base, the pump body housing surface of pump equipment, etc.) to collect data at specific times. vibration acceleration It is used to reflect the mechanical shock response of equipment.

[0027] Temperature sensors (such as thermocouples) are placed in areas of concentrated heat generation or key heat dissipation contact surfaces (such as the surface of the motor stator winding housing or the heat dissipation area of ​​the fan bearing housing) to collect data at specific times. temperature It is used to characterize changes in the thermal environment of equipment.

[0028] A current sensor (such as a Hall effect current sensor) is placed at the power input terminal of the device to collect data at specific times. current It is used to characterize changes in the electrical load of equipment.

[0029] In this embodiment, various sensors sample signals at fixed time intervals and are synchronously triggered using a sampling time base signal generated by a unified oscillation clock source inside the rotary drive electromechanical equipment. The time base signal is distributed to various sensors through the same clock reference to achieve synchronous acquisition of vibration acceleration signals, temperature signals, and current signals in the time dimension, thereby ensuring that the multi-source signals corresponding to the same sampling moment have time consistency.

[0030] S2. Establish vibration reference quantities, temperature reference quantities, and current reference quantities based on the thermal balance state of the equipment.

[0031] S21. Determine whether the equipment has reached thermal equilibrium based on the temperature signal.

[0032] During sampling, samples are taken at fixed time intervals, the sampling time interval being... The sampling time interval is The determination process is as follows: First, the constraint condition is based on the highest effective frequency of the vibration acceleration signal. According to the ISO 10816 series of standards, the upper limit of the vibration analysis frequency band for typical rotary-driven electromechanical equipment (rated speed 3000 r / min) is defined. The frequency band for vibration analysis of the vibration acceleration signal is set to 2000Hz, meaning the range of 0–2000Hz is used to characterize the vibration changes during the operation of rotary-driven electromechanical equipment. Based on the Nyquist sampling theorem, to avoid spectral folding effects caused by high-frequency components of the vibration signal during discrete sampling, the sampling frequency is... Must meet: .

[0033] In this embodiment, 5000Hz is selected as the sampling frequency, which provides an engineering margin of about 25% on the basis of meeting the minimum sampling frequency requirement of Nyquist, so as to reduce the risk of spectrum folding caused by the non-ideal roll-off characteristics of the anti-aliasing filter.

[0034] In this embodiment, the goal of processing the vibration acceleration signal is to construct a degradation characterization variable based on time evolution. Therefore, the sampling frequency constraint is transformed into a design constraint on the time resolution capability of the vibration change process. The 5000Hz sampling frequency is used to ensure that the signal change process within the 2000Hz vibration analysis frequency band can be discretely acquired and serves as the basis for determining the subsequent sampling time interval.

[0035] The fluctuations in the current signal are mainly caused by changes in the power grid load and fluctuations in the operating load of the equipment, with a fundamental frequency of 50Hz. The processing objective of this embodiment is to construct the cumulative characteristic quantity of the current amplitude changing over time, rather than to reconstruct and analyze the high-frequency components of the instantaneous waveform. Therefore, the high-frequency switching harmonics introduced by PWM modulation are not considered as the target object. Under the sampling conditions selected in this embodiment, the low-frequency modulation components related to the current fundamental frequency and the current amplitude envelope can meet the requirements of discrete time series expression, thus being used to characterize the long-term changing trend of the electrical load.

[0036] The temperature signal is determined by the heat conduction and thermal inertia processes of the equipment, and the dynamic response of the temperature signal is controlled by the thermal time constant. The thermal time constant of typical rotary drive electromechanical equipment is usually in the range of 5–20 seconds, and the temperature change process has obvious low-frequency characteristics, with an effective change frequency band far below 1Hz. Under the selected sampling conditions, the temperature change between adjacent sampling points is at a very small scale, which does not affect the time alignment consistency of the temperature signal.

[0037] Taking into account the constraints of embedded processor computing resources, storage overhead, and real-time requirements of multivariate synchronous fusion computing for rotary-driven electromechanical equipment, an engineering mapping optimization process is performed on the theoretical minimum sampling period while meeting the constraint of vibration signal time resolution capability.

[0038] In this embodiment, the sampling time interval is determined based on the 5000Hz sampling frequency. for: .

[0039] Sampling time interval This is used to construct a multi-source synchronous data sequence under a unified time index system, so as to ensure the alignment and fusion of vibration acceleration signals, temperature signals and current signals under the same time reference, thereby constructing a comprehensive state action evolution quantity based on time accumulation characteristics.

[0040] To characterize the relationship between vibration acceleration signals, temperature signals, and current signals, it is necessary to gradually transform the three types of signals from their original sampled values ​​into cumulative state quantities that can characterize the time evolution features.

[0041] In this embodiment, a reference standard is first established based on the calibration process under standard operating conditions of the equipment. The standard operating conditions include the rated speed. Rated power and ambient temperature The environmental conditions meet the motor testing environment requirements specified in GB / T 755-2019 standard. Specifically, the rated speed... Rated power All parameters are derived from the equipment nameplate calibration parameters. The reference references include vibration reference values, temperature reference values, and current reference values.

[0042] During equipment operation, the first step is to determine whether the equipment has reached thermal equilibrium based on the temperature signal.

[0043] In this embodiment, the average rate of temperature change is defined as: ; in, Indicates the time of data collection The average rate of temperature change; Collection time Temperature; This indicates the number of sampling points corresponding to the temperature determination time window. The formula for calculating the number of sampling points corresponding to the temperature determination time window is: ; in, In this embodiment, the temperature determination time window is represented. Set to 2 seconds.

[0044] The number of sampling points corresponding to the thermal equilibrium determination window is defined by the following formula: ; in, In this embodiment, the continuous determination time window for thermal equilibrium is indicated. Set to 2 seconds; This indicates the number of sampling points for continuous thermal balance determination.

[0045] When the sum of the number of sampling points in the temperature determination time window and the number of sampling points in the thermal balance determination window exceeds a preset threshold, the thermal balance state determination begins.

[0046] When the average temperature change rate within the thermal equilibrium determination window is less than a preset threshold, the determination device enters a thermal equilibrium state. The formula for calculating the average temperature change rate within the thermal equilibrium determination window is: ; In the formula, The average rate of temperature change within the thermal equilibrium determination window. This indicates the number of sampling points within the thermal balance determination window. express The average rate of temperature change at any given time. In this embodiment, the threshold for the average rate of temperature change within the thermal equilibrium determination window is [value missing]. .

[0047] S22. Establish a calibration interval by taking the moment when the equipment reaches thermal equilibrium as the starting moment of calibration.

[0048] ; in, Indicates the calibration interval; Indicates the initial moment when the equipment reaches thermal equilibrium; Indicates the calibration duration.

[0049] S23. Determine the number of calibration sampling points based on the calibration interval length and sampling time interval.

[0050] The formula for calculating the number of calibration sampling points is: ; in, This indicates the number of sampling points during the calibration phase. In this embodiment, when hour, ; 60s indicates rounding down; 60s indicates the calibration duration.

[0051] S24. Calculate the vibration reference quantity, temperature reference quantity, and current reference quantity.

[0052] The vibration reference quantity is the root mean square value of the vibration acceleration sequence of the equipment under thermal equilibrium conditions, and its calculation formula is: ; The temperature reference quantity is the average value of the temperature sampling sequence of the equipment under thermal equilibrium conditions, and its calculation formula is: ; The current reference quantity is the root mean square value of the current sampling sequence of the equipment under thermal equilibrium conditions, and its calculation formula is: ; In the formula, Indicates the vibration reference quantity; Indicates a temperature reference quantity; Indicates a current reference quantity; Indicates the number of sampling points during the calibration phase; This represents the nth discrete sampling time within the calibration interval.

[0053] S3. Construct the cumulative vibration response, cumulative vibration trend, cumulative temperature change, cumulative absolute temperature exposure, and cumulative current change, respectively.

[0054] This invention constructs an intermediate quantity for vibration acceleration signals that can simultaneously reflect instantaneous impact response and changing trends.

[0055] The vibration change is constructed based on the difference in vibration acceleration between adjacent sampling points: ; in, Indicates the time of data collection The amount of vibration change reflects the intensity of vibration changes in the equipment over adjacent time intervals. Initialization ; Indicates the time of data collection The vibration acceleration; Indicates the first term within the calibration interval Each discrete sampling time, .

[0056] To characterize the cumulative mechanical vibration experienced by the equipment throughout its operation, a cumulative vibration response is introduced, and its calculation formula is as follows: ; in, Indicates the time of data collection The cumulative vibration response is used to characterize the degree of time accumulation of mechanical vibration on the equipment during operation; Indicates the time of data collection The absolute value of vibration acceleration.

[0057] Subsequently, to characterize the cumulative effect of vibration change trend over time, the vibration change is accumulated over time to construct the cumulative vibration change trend, which is calculated as follows: ; in, Indicates the time of data collection The cumulative vibration change trend is used to characterize the continuous accumulation of vibration change trend over time during the entire operation of the equipment.

[0058] Temperature affects equipment degradation primarily through two different time-scale mechanisms: one is the thermal cycling fatigue effect caused by temperature fluctuations, and the other is the thermal activation aging effect of materials caused by long-term high-temperature environments.

[0059] Among them, the thermally activated aging effect refers to the enhanced diffusion and chemical reaction processes within the equipment material under continuous high temperature conditions, which leads to aging of insulating materials, accelerated metal oxidation, etc. This is related to the long-term exposure level of temperature; therefore, in addition to constructing the cumulative amount of temperature change, it is also necessary to construct the absolute amount of temperature exposure.

[0060] Therefore, in this embodiment, the temperature change is first constructed using the temperature difference between adjacent sampling points: ; In the formula, Indicates the time of data collection The temperature change reflects the intensity of thermal fluctuations in the equipment over adjacent time intervals, and is initialized. ; Indicates the time of data collection The temperature.

[0061] Then, the temperature changes are accumulated over time to form the cumulative temperature change: ; In the formula, Indicates the time of data collection The cumulative temperature change is used to characterize the degree of thermal fatigue accumulation caused by temperature fluctuations during the entire operation of the equipment.

[0062] Meanwhile, to characterize the thermally activated aging effect of equipment materials under long-term high-temperature conditions, a dimensionless form of absolute temperature exposure is introduced: ; In the formula, Indicates the time of data collection Absolute temperature exposure is used to characterize the cumulative effect of temperature levels experienced by equipment over time during operation.

[0063] After the thermal response characterization is completed, in order to further characterize the continuous impact of electrical load changes on the thermal accumulation process and material degradation process, it is necessary to introduce the time evolution characteristics of the current signal.

[0064] During the operation of rotary-driven electromechanical equipment, the current signal changes the level of internal power loss, which is then converted into heat input, thus affecting the absolute temperature exposure. These factors collectively influence the degradation trend of the equipment. Therefore, it is necessary to construct an intermediate variable from the perspective of the cumulative effect of current changes over time.

[0065] First, the change in current is constructed by the difference in current between adjacent sampling points: , In the formula, Indicates the time of data collection The change in current is used to characterize the fluctuation intensity of the electrical load within adjacent time intervals, and is initialized. ; Indicates the time of data collection The current.

[0066] Then, the changes in current are accumulated over time to construct the cumulative changes in current: ; In the formula, Indicates the time of data collection The cumulative change in current is used to characterize the intensity of the cumulative fluctuation of the load over time throughout the entire operation process.

[0067] S4. Construct vibration response characterization quantities, thermal response characterization quantities, and electrothermal effect characterization quantities, and establish the temporal correlation between mechanical state, thermal state, and electrothermal effect state.

[0068] The vibration response characterization quantity is constructed by obtaining the cumulative amount of vibration response and the cumulative amount of vibration change trend, and its calculation formula is as follows: ; in, Indicates the time of data collection The vibration response characterization quantity is used to characterize the degree of cumulative mechanical state degradation of equipment under vibration. This indicates that the accumulated vibration energy has been normalized to prevent the accumulated vibration energy value from growing unbounded over time. This represents the hyperbolic tangent function, used to map variable parameters to an interval. ; This represents a bounded trend enhancement factor constructed based on the cumulative amount of vibration change trends. As a multiplicative modulation factor, it acts on the vibration energy accumulation term to apply an amplification effect that increases with time to the vibration energy accumulation term, thereby achieving the characterization effect that the equipment vibration degradation gradually accelerates with the changing trend.

[0069] Subsequently, a thermal response characterization quantity is constructed, the calculation formula of which is: ; In the formula, Indicates the time of data collection The thermal response characterization quantity is used to describe the coupled effect of thermal fatigue caused by temperature fluctuations and thermal activation aging caused by long-term temperature exposure. This indicates that the cumulative temperature change has been normalized to prevent the thermal fatigue term from growing unbounded over time. This represents a logarithmic growth map constructed based on absolute temperature exposure, used to characterize the nonlinear aging enhancement effect of equipment materials under long-term high-temperature conditions.

[0070] Since changes in electrical load alter the level of internal power loss in equipment and further affect the evolution of the equipment's thermal state, there is a time-dependent relationship between changes in current and absolute temperature exposure.

[0071] Subsequently, to further characterize the comprehensive impact of electrical load fluctuations on the equipment state evolution process under thermal state evolution conditions, a characterization quantity for electrothermal effects was constructed: ; In the formula, Indicates the time of data collection The electrothermal effect is characterized by a quantity used to describe the overall contribution of electrical load fluctuations to the equipment degradation process under heat accumulation conditions. This means that the cumulative current change is compressed in logarithmic form to suppress the nonlinear divergence of the cumulative current change over time, while retaining the growth trend information of the cumulative current change. This represents the enhancement mapping term based on the load-thermal coupling factor, where, This is used to perform nonlinear compression on the load-thermal coupling factor, making its variation smoother; the constant 1 is used to perform baseline shifting on the compressed result, ensuring that the enhancement mapping term remains no less than 1 across the entire value range, thus guaranteeing... The electrothermal effect characterization quantities maintain a positive modulation relationship.

[0072] The formula for calculating the load-thermal coupling factor is: ; In the formula, Indicates the time of data collection The load-thermal coupling factor is used to characterize the degree of comprehensive state response formed by the combined effect of electrical load variation and long-term thermal exposure of equipment. This indicates that the cumulative change in current is normalized to prevent the cumulative value of current change from growing unbounded over time. This indicates that the absolute temperature exposure has been normalized to characterize the saturation growth characteristics of equipment under long-term high-temperature conditions.

[0073] S5. Degradation propagation response factors are constructed based on vibration response characterization, thermal response characterization, and electrothermal effect characterization, and further degradation propagation evolution quantity and degradation propagation rate are formed.

[0074] because , and electrothermal effect characterization quantity These are used to describe mechanical, thermal, and electrothermal states, respectively. Their physical dimensions and numerical ranges differ; therefore, they need to be uniformly mapped to the same state space for normalization. ; ; ; In the formula, Indicates the time of data collection normalized vibration ; Indicates the time of data collection The normalized temperature response characterization quantity; Indicates the time of data collection Normalized electrothermal effect The range of values ​​for each normalized state characterization quantity is as follows: .

[0075] Subsequently, based on the normalized vibration response characterization, thermal response characterization, and electrothermal effect characterization, a degradation propagation response factor is constructed, and its calculation formula is as follows:

[0076] In the formula, Indicates the time of data collection The degradation propagation response factor is used to characterize the degree of increased correlation between mechanical vibration state, thermal state, and electrothermal state over time. It is used to describe the correlation and change characteristics between different physical state characterization quantities, rather than to represent the change magnitude of a single physical parameter; Used to characterize the degree of correlation response when the mechanical vibration state response and the thermal state response are enhanced together within the same time window; Used to characterize the degree of correlation between the electrothermal action state and the thermal state response; Indicates the time of data collection The normalized change in vibration response, when hour, ,when hour, Set as ; Indicates the time of data collection The normalized change in electrothermal effect, when hour, ,when hour, Set as ; It represents the degree of joint change between the normalized vibration response change and the normalized electrothermal effect change, and is used to reflect the synchronous change relationship between the vibration state change trend and the electrothermal effect state change trend. This is used to perform nonlinear compression on the combined change between the normalized vibration response change and the electrothermal effect change, reducing... Excessive influence of large changes on degradation propagation response factors.

[0077] Furthermore, the degradation propagation evolution quantity is constructed, and its calculation formula is: ; In the formula, Characterizing the acquisition time The degradation propagation evolution quantity is used to characterize the cumulative change process of the correlation between mechanical vibration state, thermal state and electrothermal action state in the time dimension, and serves as the basic state quantity for subsequent degradation propagation rate calculation.

[0078] The formula for calculating the degradation propagation rate is: ; In the formula, Indicates the sampling time The degradation propagation rate is used to characterize the rate at which the amount of equipment degradation propagation and evolution changes over time. The degradation propagation rate is from... Begin calculation; Indicates the sampling time The amount of degradation, propagation, and evolution.

[0079] S6. Obtain the degradation propagation reference rate from the calibration data under standard operating conditions of the equipment, and dynamically correct the degradation propagation reference rate by combining the electrothermal effect state during operation to form a normalized degradation propagation rate offset.

[0080] Specifically, based on the calibration data collected under standard operating conditions of the equipment, the degradation propagation reference rate is calculated and dynamically corrected to obtain the corrected degradation propagation reference rate. Based on the degradation propagation rate and the corrected degradation propagation reference rate, a normalized degradation propagation rate offset is constructed.

[0081] Calibration is performed under standard operating conditions after the equipment is manufactured. Once the equipment reaches thermal equilibrium, calibration data acquisition begins. The calibration data is a discrete-time series of degradation propagation rates calculated from continuously acquired vibration acceleration, temperature, and current signals within the calibration interval. , .

[0082] In this embodiment, the median of the discrete-time series of degradation propagation rates is taken as the baseline degradation propagation rate of the device under standard operating conditions: ; In the formula, This indicates the reference rate of degradation propagation of the equipment under factory-calibrated operating conditions; This represents the function for calculating the median.

[0083] To accommodate deviations between actual operating conditions and calibration conditions, the degradation propagation reference rate is dynamically corrected. ; In the formula, Indicates the time of data collection The modified degradation propagation reference rate is obtained by using the correlation response between the electrical load state and the thermal response state formed during equipment operation to adjust the normal degradation propagation level under different operating conditions, so that the degradation propagation reference rate changes dynamically with the actual operating conditions of the equipment. Characterizes the degree of enhancement in the propagation of normal degradation caused by electrothermal effects in the current operating state of the equipment.

[0084] To describe the deviation of the current device from the corrected degradation propagation reference rate, a normalized degradation propagation rate offset is introduced, calculated as follows: ; In the formula, Indicates the time of data collection The normalized degradation propagation rate offset is used to characterize the degree of deviation of the current degradation propagation rate from the corrected degradation propagation reference rate after dynamic correction by the operating state. To represent extremely small positive numbers, avoid In this embodiment, the denominator is zero. Pick .

[0085] S7. Determine whether the equipment has an accelerating trend of degradation propagation based on the degree of deviation in the degradation propagation rate.

[0086] S71. Calculate the standard deviation of the normalized degradation propagation rate offset: ; In the formula, The standard deviation of the normalized degradation propagation rate offset; This represents the average value of the normalized degradation propagation rate offset.

[0087] The formula for calculating the average value of the normalized degradation propagation rate offset is as follows: .

[0088] S72. Threshold for judging the degradation trend of computing equipment: ; In the formula, This indicates that the rate of equipment degradation propagation deviates from the threshold.

[0089] S73. Compare the normalized degradation propagation rate offset with the equipment degradation trend discrimination threshold to determine whether the equipment has an accelerated degradation propagation trend.

[0090] Specifically, the normalized degradation propagation rate offset is compared with the equipment degradation trend discrimination threshold, and the degradation trend of rotary drive electromechanical equipment is judged as follows: when At that time, it was determined that the equipment showed an accelerated trend of degradation.

[0091] when At that time, it was determined that the rate of equipment degradation propagation was within the normal fluctuation range. Among them, This represents the absolute value of the normalized degradation propagation rate offset.

[0092] when When the current degradation propagation rate of the device is determined to be lower than the corrected degradation propagation reference rate, the device does not exhibit degradation propagation acceleration exceeding the degradation propagation reference rate.

[0093] The above scheme was used to determine the degradation trend of rotary drive electromechanical equipment.

[0094] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0095] It should be noted that the terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in sequences other than those illustrated or described herein.

[0096] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for determining the degradation trend of rotary-driven electromechanical equipment, characterized in that, include: S1. Simultaneously acquire vibration acceleration signals, temperature signals, and current signals using the same clock reference; S2. Establish vibration reference quantities, temperature reference quantities, and current reference quantities based on the thermal balance state of the equipment; S3. Construct the cumulative vibration response, cumulative vibration trend, cumulative temperature change, absolute temperature exposure, and cumulative current change, respectively. S4. Construct vibration response characterization quantities, thermal response characterization quantities, and electrothermal effect characterization quantities, and establish the temporal correlation between mechanical state, thermal state, and electrothermal effect state. S5. Degradation propagation response factors are constructed based on vibration response characterization, thermal response characterization, and electrothermal effect characterization, and further degradation propagation evolution quantity and degradation propagation rate are formed. S6. Obtain the degradation propagation reference rate from the calibration data under the standard operating conditions of the equipment, and dynamically correct the degradation propagation reference rate in combination with the electrothermal effect state during operation to form a normalized degradation propagation rate offset. S7. Determine whether the equipment has an accelerating trend of degradation propagation based on the degree of deviation in the degradation propagation rate.

2. The method for determining the degradation trend of rotary-driven electromechanical equipment as described in claim 1, characterized in that, Step S2 includes: S21. Determine whether the equipment has reached thermal equilibrium based on the temperature signal; S22. Establish a calibration interval by taking the moment when the equipment reaches thermal equilibrium as the calibration start moment; S23. Determine the number of calibration sampling points based on the calibration interval length and sampling time interval; S24. Calculate the vibration reference quantity, temperature reference quantity, and current reference quantity.

3. The method for determining the degradation trend of rotary-driven electromechanical equipment as described in claim 2, characterized in that, Step S21 includes: When the sum of the number of sampling points in the temperature determination time window and the number of sampling points in the heat balance determination window is greater than the preset threshold, the heat balance state determination is started. When the average temperature change rate within the thermal balance determination window is less than a preset threshold, the determination device enters a thermal balance state. The formula for calculating the average temperature change rate within the thermal equilibrium determination window is: ； In the formula, The average rate of temperature change within the thermal equilibrium determination window. This indicates the number of sampling points within the thermal balance determination window. express The average rate of temperature change at any given time.

4. The method for determining the degradation trend of rotary-driven electromechanical equipment as described in claim 3, characterized in that, In step S24, the vibration reference quantity is the root mean square value of the vibration acceleration sequence of the equipment under thermal equilibrium state, and its calculation formula is: ； The temperature reference quantity is the average value of the temperature sampling sequence of the equipment under thermal equilibrium conditions, and its calculation formula is: ； The current reference quantity is the root mean square value of the current sampling sequence of the equipment under thermal equilibrium conditions, and its calculation formula is: ； In the formula, Indicates the vibration reference quantity; Indicates a temperature reference quantity; Indicates a current reference quantity; Indicates the number of sampling points during the calibration phase; This represents the nth discrete sampling time within the calibration interval.

5. The method for determining the degradation trend of rotary-driven electromechanical equipment as described in claim 4, characterized in that, Step S3 includes: Based on vibration acceleration and vibration reference quantities, construct the cumulative quantity of vibration response and the cumulative quantity of vibration change trend; Based on temperature and temperature baseline, construct the cumulative temperature change and absolute temperature exposure; Based on current and current reference quantity, construct the cumulative current change quantity; The formula for calculating the cumulative vibration response is: ； In the formula, Indicates the time of data collection The cumulative amount of vibration response; Indicates the time of data collection The absolute value of vibration acceleration; Indicates the sampling time interval; The formula for calculating the cumulative amount of vibration change trend is: ； In the formula, Indicates the time of data collection The cumulative amount of vibration change trend; Indicates the time of data collection The amount of vibration change; The formula for calculating the cumulative temperature change is: ； In the formula, Indicates the time of data collection The cumulative amount of temperature change; The formula for calculating absolute temperature exposure is: ； In the formula, Indicates the time of data collection Absolute temperature exposure; The formula for calculating the cumulative change in current is: ； In the formula, Indicates the time of data collection The cumulative change in current.

6. The method for determining the degradation trend of rotary-driven electromechanical equipment as described in claim 5, characterized in that, In step S4, the formula for calculating the vibration response characterization quantity is: ； In the formula, Indicates the time of data collection Vibration response characterization quantity; The formula for calculating the thermal response characterization quantity is: ； In the formula, Indicates the time of data collection Thermal response characterization quantity; The formula for calculating the characteristic quantity of electrothermal effect is: ； In the formula, Indicates the time of data collection The characteristic quantity of electrothermal effect; Collection time The cumulative change in current; Indicates the time of data collection The load-thermal coupling factor.

7. The method for determining the degradation trend of rotary-driven electromechanical equipment as described in claim 6, characterized in that, In step S5, the formula for calculating the degradation propagation response factor is: ； In the formula, Indicates the time of data collection Degradation propagation response factor; Indicates the time of data collection The normalized vibration response characterization quantity; Indicates the time of data collection The normalized temperature response characterization quantity; Indicates the time of data collection Normalized electrothermal effect characterization quantity; Used to characterize the degree of correlation response when the mechanical vibration state response and the thermal state response are enhanced together within the same time window; This indicates the degree of correlation between the electrothermal action state and the thermal state response; Indicates the time of data collection The normalized change in vibration response; Indicates the time of data collection The normalized change in electrothermal effect.

8. The method for determining the degradation trend of rotary-driven electromechanical equipment as described in claim 7, characterized in that, In step S6, the formula for calculating the degradation propagation evolution quantity is: ； In the formula, Indicates the time of data collection The amount of degradation, propagation, and evolution.

9. The method for determining the degradation trend of rotary-driven electromechanical equipment as described in claim 8, characterized in that, In step S6, the formula for calculating the normalized degradation propagation rate offset is: ； In the formula, Indicates the time of data collection Normalized degenerate propagation rate offset; Indicates the sampling time The rate of degradation propagation; Indicates the time of data collection The revised degradation propagation baseline rate; To represent extremely small positive numbers, avoid having a denominator of zero; The formula for calculating the degradation propagation rate is: ； The formula for calculating the modified degradation propagation baseline rate is: ； In the formula, Indicates the sampling time The amount of degradation, propagation, and evolution.

10. The method for determining the degradation trend of rotary-driven electromechanical equipment as described in claim 9, characterized in that, Step S7 includes: S71. Calculate the standard deviation of the normalized degradation propagation rate offset: ； In the formula, The standard deviation of the normalized degradation propagation rate offset; This represents the average value of the normalized degradation propagation rate offset. S72. Threshold for judging the degradation trend of computing equipment: ； In the formula, This indicates that the rate of equipment degradation propagation deviates from the threshold; S73. Compare the normalized degradation propagation rate offset with the equipment degradation trend discrimination threshold to determine whether the equipment has an accelerated degradation propagation trend.

Images