A method for detecting rotor broken bar and thin bar faults

Abstract

The present invention relates to the technical field related to electrical performance testing and detection, and discloses a rotor broken bar and thin bar fault detection method. Based on a fault parameter library, an operating coefficient, an ambient temperature change rate, an operating error coefficient, an impact influence coefficient, a dynamic load value, a fatigue aging coefficient and an idle aging coefficient are extracted to obtain a first fault risk coefficient and a second fault risk coefficient. The first fault risk coefficient and the second fault risk coefficient are comprehensively calculated to finally obtain a comprehensive fault risk coefficient. According to the comprehensive fault risk coefficient, it is judged whether to execute a fault warning instruction. The rotor broken bar and thin bar faults are analyzed from multiple angles from different working environment states of the motor, different temperature mutations, damage caused by improper operation, the number of times the motor is impacted, the motor load mutation, the fatigue degree of internal components and the sudden start-up of the idle motor, thereby ensuring the accuracy of the rotor broken bar and thin bar faults.

Description

Technical Field

[0001] The invention relates to the technical field of motor rotors, and in particular to a method for detecting rotor broken bars and thin bars faults. Background Art

[0002] Broken rotor bars and thin strip faults are common types of faults in motors and related mechanical equipment, which can have a significant impact on the performance and safety of the equipment. Broken rotor bar faults refer to the situation where one or more rotor bars (such as windings or rotor coils) of the rotor of a motor or rotating equipment breaks during operation due to external force, material fatigue or other reasons. This usually causes the rotor to lose balance, thereby causing serious equipment failure. Thin strip faults refer to small cracks or microscopic defects in the rotor. They usually do not cause obvious problems in the early stages, but if not handled in time, they may develop into serious failures. Existing technologies mainly rely on the following methods to detect and prevent broken rotor bars and thin strip faults: Visual inspection: manually inspect the appearance of the rotor to look for obvious fractures or deformations. Vibration monitoring: use vibration analysis technology to monitor the operating status of the equipment and determine whether there is a fault. These methods can help identify faults to a certain extent, but visual inspection and vibration monitoring can often only detect obvious faults and it is difficult to detect tiny cracks or early damage. Summary of the invention

[0003] 1. Technical issues to be resolved

[0004] In view of the deficiencies in the prior art, the present invention provides a method for detecting broken bars and thin strips of rotor faults, which has the advantages of detecting broken bars and thin strips of motor rotor faults and solves the above-mentioned technical problems.

[0005] To achieve the above object, the present invention provides the following technical solution: a method for detecting broken rotor bars and thin rotor bars, comprising the following steps:

[0006] S1: Collect the working data and environmental impact parameters of the current motor, and combine the working data and environmental impact parameters to build a fault parameter library;

[0007] S2: Extracting operating coefficients based on the fault parameter library , Ambient temperature change rate , Operation error coefficient , Impact influence coefficient , Dynamic load value , fatigue aging coefficient and idle aging factor ;

[0008] S3: Extract the operating coefficient , Ambient temperature change rate , Operation error coefficient and impact coefficient , the first fault risk coefficient is obtained by comprehensive calculation , and extract dynamic load values , fatigue aging coefficient and idle aging factor Get the second failure risk factor ;

[0009] S4: The first failure risk coefficient calculated in S3 is obtained and the second failure risk factor The comprehensive calculation finally obtains the comprehensive failure risk coefficient ;

[0010] S5: Based on comprehensive failure risk factor Determine whether to execute the fault warning instruction.

[0011] As a preferred technical solution of the present invention, in step S2, the operating coefficient is extracted based on the fault parameter library. The specific steps are as follows:

[0012] Step S2.a1: Obtain the vibration noise in the working data based on the fault parameter library and obtain the maximum deviation rate of vibration noise , the specific expression is as follows:

[0013] in, Indicates the motor vibration noise at the first running moment, , No. Motor vibration noise at each running moment, , No. The motor vibration noise during each operation, Indicates the maximum safe value of motor vibration noise. Indicates total The maximum value of the motor vibration noise at each running moment;

[0014] Step S2.a2: Obtain the speed in the working data based on the fault parameter library to obtain the speed fluctuation deviation value , the specific expression is as follows: in, Respectively represent the motor speed at the first running moment, , No. Motor speed at each running moment, , No. The motor speed at each running moment, Indicates total The maximum value of the motor speed at each running moment, Indicates total The minimum value of the motor speed at each running moment, Indicates total The average value of the motor speed at each running moment;

[0015] Step S2.a3: Based on the maximum deviation rate of vibration noise in step S2.a1 and the speed fluctuation deviation value in step S2.a2 The operating coefficient is obtained by comprehensive calculation ;

[0016] in, Indicates the maximum deviation rate of vibration noise, Indicates the speed fluctuation deviation value.

[0017] As a preferred technical solution of the present invention, in step S2, the ambient temperature change rate is extracted based on the fault parameter library. The specific steps are as follows:

[0018] in, express and The interval time between Indicates the ambient temperature at the first operating moment, , No. Ambient temperature at each operating time, , No. Ambient temperature at each operating time, Indicates total The maximum value of the ambient temperature during operation. common The minimum value of the ambient temperature during operation.

[0019] As a preferred technical solution of the present invention, in step S2, the operation error coefficient is extracted based on the fault parameter library. The specific expression is as follows:

[0020] in, Indicates the number of maintenance errors. Indicates the number of motor fault reports.

[0021] As a preferred technical solution of the present invention, in step S2, the impact influence coefficient is extracted based on the fault parameter library. The specific expression is as follows:

[0022] in, represents a natural constant, Indicates the number of times the motor is impacted during electric shock operation.

[0023] As a preferred technical solution of the present invention, the operating coefficient extracted in step S3 is , Ambient temperature change rate , Operation error coefficient , Impact influence coefficient , the first fault risk coefficient is obtained by comprehensive calculation The specific expression is as follows:

[0024] in, represents the operating coefficient, Indicates the rate of change of ambient temperature, represents the operating error coefficient, Represents the impact coefficient.

[0025] As a preferred technical solution of the present invention, in step S2, the dynamic load value is extracted based on the fault parameter library. The steps to obtain are as follows:

[0026] Step 2c.1: Get The motor load value at each running moment is expressed as follows:

[0027]

[0028] in, represents the motor load data set, Respectively represent the motor load at the first running moment, , No. Motor load at each running moment, , No. Motor load at each running moment;

[0029] Step 2c.2: Calculate the motor load surge , the specific expression is as follows:

[0030] in, Indicates Motor load at each running moment, Indicates Motor load at each running moment, Indicates The motor load mutation value at each running moment, all the calculated motor load mutation values ​​constitute the motor load mutation set, the specific expression is as follows:

[0031] in, represents the sudden change set of motor load, Respectively represent the calculated The sudden change value of the motor load at each running moment, , No. The sudden change value of the motor load at each running moment, , No. Sudden change value of motor load at each running moment;

[0032] Step 2c.3: Calculate the fault parameter library to extract dynamic load values , the specific expression is as follows:

[0033] in, Represents the motor load mutation set The maximum value, Indicates the standard load of the motor.

[0034] As a preferred technical solution of the present invention, the fatigue aging coefficient The calculation expression is as follows:

[0035] in, Indicates the current fatigue strength, represents the initial fatigue strength;

[0036] The idle aging factor The specific expression is as follows:

[0037] in, Indicates idle years, Represents the idle aging factor.

[0038] As a preferred technical solution of the present invention, in step S3, based on the dynamic load value , fatigue aging coefficient and idle aging factor Get the second failure risk factor The specific expression is as follows:

[0039] in, Dynamic load value, represents the fatigue aging coefficient, Represents the idle aging factor.

[0040] As a preferred technical solution of the present invention, in step S4, the first fault risk coefficient calculated in step S3 is and the second failure risk factor The comprehensive calculation finally obtains the comprehensive failure risk coefficient The specific expression is as follows:

[0041]

[0042] in, and Respectively represent two weight coefficients whose sum is 1;

[0043] In step S5, based on the comprehensive failure risk coefficient The specific process of judging whether to execute the fault warning instruction is as follows:

[0044] When the comprehensive failure risk factor Comprehensive risk threshold When the fault warning instruction is not executed;

[0045] when Comprehensive risk threshold Comprehensive failure risk factor The second comprehensive risk threshold When the rotor thin strip fault warning is executed;

[0046] When the comprehensive failure risk factor The second comprehensive risk threshold When the rotor bar broken fault warning is executed.

[0047] Compared with the prior art, the present invention provides a method for detecting rotor broken bars and thin bars faults, which has the following beneficial effects:

[0048] The present invention collects the working data and environmental impact parameters of the current motor when it is working, extracts the operating coefficient, the ambient temperature change rate, the operating error coefficient, the impact impact coefficient, the dynamic load value, the fatigue aging coefficient and the idle aging coefficient based on the fault parameter library, and comprehensively calculates the first fault risk coefficient and the second fault risk coefficient. The first fault risk coefficient and the second fault risk coefficient are comprehensively calculated to finally obtain the comprehensive fault risk coefficient, so as to judge whether to execute the fault warning instruction according to the comprehensive fault risk coefficient, and analyzes the rotor broken bar and thin bar faults from multiple angles from different working environment states of the motor, different temperature mutations, damage caused by improper operation, the number of times the motor is impacted, the motor load mutation, the fatigue degree of internal components and the sudden start-up of the idle motor, thereby ensuring the accuracy of the rotor broken bar and thin bar faults. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 It is a schematic diagram of the system framework of the present invention. DETAILED DESCRIPTION

[0050] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0051] See also Figure 1 A method for detecting rotor broken bars and thin bars faults comprises the following steps:

[0052] S1: Collect the working data and environmental impact parameters of the current motor, and combine the working data and environmental impact parameters to build a fault parameter library;

[0053] S2: Extracting operating coefficients based on the fault parameter library , Ambient temperature change rate , Operation error coefficient , Impact influence coefficient , Dynamic load value , fatigue aging coefficient and idle aging factor ;

[0054] In step S2, the operating coefficient is extracted based on the fault parameter library. The specific steps are as follows:

[0055] Step S2.a1: Obtain the vibration noise in the working data based on the fault parameter library and obtain the maximum deviation rate of vibration noise , the specific expression is as follows:

[0056]

[0057] in, Indicates the motor vibration noise at the first running moment, , No. Motor vibration noise at each running moment, , No. The motor vibration noise during each operation, Indicates the maximum safe value of motor vibration noise. Indicates total The maximum value of the motor vibration noise at each running moment;

[0058] Step S2.a2: Obtain the speed in the working data based on the fault parameter library to obtain the speed fluctuation deviation value , the specific expression is as follows:

[0059] in, Respectively represent the motor speed at the first running moment, , No. Motor speed at each running moment, , No. The motor speed at each running moment, Indicates total The maximum value of the motor speed at each running moment, Indicates total The minimum value of the motor speed at each running moment, Indicates total The average value of the motor speed at each running moment;

[0060] Step S2.a3: Based on the maximum deviation rate of vibration noise in step S2.a1 and the speed fluctuation deviation value in step S2.a2 The operating coefficient is obtained by comprehensive calculation ;

[0061] in, Indicates the maximum deviation rate of vibration noise, Indicates the speed fluctuation deviation value.

[0062] In step S2, the ambient temperature change rate is extracted based on the fault parameter library. The specific steps are as follows:

[0063]

[0064] in, express and The interval time between Indicates the ambient temperature at the first operating moment, , No. Ambient temperature at each operating time, , No. Ambient temperature at each operating time, Indicates total The maximum value of the ambient temperature during operation. common The minimum value of the ambient temperature at the time of operation, in step S2, the operation error coefficient is extracted based on the fault parameter library The specific expression is as follows:

[0065]

[0066] in, Indicates the number of maintenance errors. Indicates the number of motor fault reports.

[0067] In step S2, the impact coefficient is extracted based on the fault parameter library to represent the number of maintenance errors. Indicates the number of motor fault reports.

[0068] In step S2, the impact coefficient is extracted based on the fault parameter library. The specific expression is as follows:

[0069]

[0070] in, represents a natural constant, Indicates the number of times the motor is impacted during the electric shock process. In step S2, the dynamic load value is extracted based on the fault parameter library. The steps to obtain are as follows:

[0071] Step 2c.1: Get The motor load value at each running moment is expressed as follows:

[0072] in, Represents the motor load data set. The motor load data is obtained by calculating the motor current and motor voltage. The specific expression is: Power factor, where Indicates The motor current at each running moment, for example, the rated voltage of a motor is 400 V, the working current is 10 A, and the power factor is 0.8. =400V×10A×0.8=3200W=3.2kW, Indicates The motor voltage at each running moment, Respectively represent the motor load at the first running moment, , No. Motor load at each running moment, , No. Motor load at each running moment;

[0073] Step 2c.2: Calculate the sudden change in motor load , the specific expression is as follows:

[0074]

[0075] in, Indicates Motor load at each running moment, Indicates Motor load at each running moment, Indicates The motor load sudden change value at each running moment, such as According to this formula, we can calculate , which can accurately reflect the comprehensive mutation of current and voltage, and all calculated motor load mutation values ​​constitute the motor load mutation set. The specific expression is as follows:

[0076]

[0077] in, represents the sudden change set of motor load, Respectively represent the calculated The sudden change value of the motor load at each running moment, , No. The sudden change value of the motor load at each running moment, , No. Sudden change value of motor load at each running moment;

[0078] Step 2c.3: Calculate the fault parameter library to extract dynamic load values , the specific expression is as follows:

[0079] in, Represents the motor load mutation set The maximum value of It ensures that when no mutation occurs, there will be no positive impact on the final result. Indicates the motor standard load, fatigue aging coefficient The calculation expression is as follows:

[0080]

[0081] in, Indicates the current fatigue strength, represents the initial fatigue strength;

[0082] Idle aging factor The specific expression is as follows:

[0083]

[0084] in, Indicates idle years, Indicates the idle aging coefficient. When the motor is idle for a long time, a sudden start may cause cracks in the rotor.

[0085] S3: Extract the operating coefficient , Ambient temperature change rate , Operation error coefficient and impact coefficient , the first fault risk coefficient is obtained by comprehensive calculation , and extract dynamic load values , fatigue aging coefficient and idle aging factor Get the second failure risk factor ;

[0086] In step S3, the extracted operating coefficient , Ambient temperature change rate , Operation error coefficient , Impact influence coefficient , the first fault risk coefficient is obtained by comprehensive calculation The specific expression is as follows:

[0087]

[0088] in, represents the operating coefficient, Indicates the rate of change of ambient temperature, represents the operating error coefficient, Indicates the impact influence coefficient, based on the dynamic load value in step S3 , fatigue aging coefficient and idle aging factor Get the second failure risk factor The specific expression is as follows:

[0089]

[0090] in, Dynamic load value, represents the fatigue aging coefficient, represents the idle aging coefficient;

[0091] S4: The first failure risk coefficient calculated in S3 is obtained and the second failure risk factor The comprehensive calculation finally obtains the comprehensive failure risk coefficient The broken rotor bars and thin strip faults are analyzed from multiple angles under different working environment conditions of the motor, different temperature changes, damage caused by improper operation, the number of times the motor is impacted, the sudden change of motor load, the fatigue degree of internal components, and the sudden start of the idle motor, thereby ensuring the accuracy of the broken rotor bars and thin strip faults. The specific expressions are as follows:

[0092]

[0093] in, and Respectively represent two weight coefficients whose sum is 1;

[0094] S5: Based on comprehensive failure risk factor Determine whether to execute the fault warning instruction;

[0095] In step S5, based on the comprehensive failure risk coefficient The specific process of judging whether to execute the fault warning instruction is as follows:

[0096] When the comprehensive failure risk factor Comprehensive risk threshold When the fault warning instruction is not executed;

[0097] when Comprehensive risk threshold Comprehensive failure risk factor The second comprehensive risk threshold When the rotor thin strip fault warning is executed;

[0098] When the comprehensive failure risk factor The second comprehensive risk threshold When the rotor bar broken fault warning is executed.

[0099] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for detecting broken rotor bars and thin rotor bars, characterized in that: The following steps are involved: S1: Collect the working data and environmental impact parameters of the current motor, and combine the working data and environmental impact parameters to build a fault parameter library; S2: Extracting operating coefficients based on the fault parameter library , Ambient temperature change rate , Operation error coefficient , Impact influence coefficient , Dynamic load value , fatigue aging coefficient and idle aging factor ; In step S2, the operating coefficient is extracted based on the fault parameter library The specific steps are as follows: Step S2.a1: Obtain the vibration noise in the working data based on the fault parameter library and obtain the maximum deviation rate of vibration noise , the specific expression is as follows: in, Indicates the motor vibration noise at the first running moment, , No. Motor vibration noise at each running moment, , No. The motor vibration noise during each operation, Indicates the maximum safe value of motor vibration noise. Indicates total The maximum value of the motor vibration noise at each running moment; Step S2.a2: Obtain the speed in the working data based on the fault parameter library to obtain the speed fluctuation deviation value , the specific expression is as follows: in, Respectively represent the motor speed at the first running moment, , No. Motor speed at each running moment, , No. The motor speed at each running moment, Indicates total The maximum value of the motor speed at each running moment, Indicates total The minimum value of the motor speed at each running moment, Indicates total The average value of the motor speed at each running moment; Step S2.a3: Based on the maximum deviation rate of vibration noise in step S2.a1 and the speed fluctuation deviation value in step S2.a2 The operating coefficient is obtained by comprehensive calculation ; in, Indicates the maximum deviation rate of vibration noise, Indicates the speed fluctuation deviation value; In step S2, the dynamic load value is extracted based on the fault parameter library The steps to obtain are as follows: Step 2c.1: Get The motor load value at each running moment is expressed as follows: in, represents the motor load data set, Respectively represent the motor load at the first running moment, , No. Motor load at each running moment, , No. Motor load at each running moment; Step 2c.2: Calculate the sudden change in motor load , the specific expression is as follows: in, Indicates Motor load at each running moment, Indicates Motor load at each running moment, Indicates The motor load mutation value at each running moment, all the calculated motor load mutation values ​​constitute the motor load mutation set, the specific expression is as follows: in, represents the sudden change set of motor load, Respectively represent the calculated The sudden change value of the motor load at each running moment, , No. The sudden change value of the motor load at each running moment, , No. Sudden change value of motor load at each running moment; Step 2c.3: Calculate the fault parameter library to extract dynamic load values , the specific expression is as follows: in, Represents the motor load mutation set The maximum value, Indicates the standard load of the motor S3: Extract the operating coefficient , Ambient temperature change rate , Operation error coefficient and impact coefficient , the first fault risk coefficient is obtained by comprehensive calculation , and extract dynamic load values , fatigue aging coefficient and idle aging factor Get the second failure risk factor ; In step S3, the extracted operating coefficient , Ambient temperature change rate , Operation error coefficient , Impact influence coefficient , the first fault risk coefficient is obtained by comprehensive calculation The specific expression is as follows: in, represents the operating coefficient, Indicates the rate of change of ambient temperature, represents the operating error coefficient, represents the impact coefficient; In step S3, based on the dynamic load value , fatigue aging coefficient and idle aging factor Get the second failure risk factor The specific expression is as follows: in, Dynamic load value, represents the fatigue aging coefficient, represents the idle aging coefficient; S4: The first failure risk coefficient calculated in S3 is obtained and the second failure risk factor The comprehensive calculation finally obtains the comprehensive failure risk coefficient ; S5: Based on comprehensive failure risk factor Determine whether to execute the fault warning instruction.

2. A method for detecting rotor broken bars and thin bars faults according to claim 1, characterized in that: In step S2, the ambient temperature change rate is extracted based on the fault parameter library The specific steps are as follows: in, Show and The interval time between Indicates the ambient temperature at the first operating moment, , No. Ambient temperature at each operating time, , No. Ambient temperature at each operating time, Indicates total The maximum value of the ambient temperature during operation. common The minimum value of the ambient temperature during operation.

3. A rotor broken bar and thin bar fault detection method according to claim 1, characterized in that: In step S2, the operation error coefficient is extracted based on the fault parameter library. The specific expression is as follows: in, Indicates the number of maintenance errors. Indicates the number of motor fault reports.

4. A method for detecting rotor broken bars and thin bars faults according to claim 1, characterized in that: In step S2, the impact coefficient is extracted based on the fault parameter library The specific expression is as follows: in, represents a natural constant, Indicates the number of times the motor is impacted during electric shock operation.

5. A method for detecting rotor broken bars and thin bars faults according to claim 1, characterized in that: The fatigue aging coefficient The calculation expression is as follows: in, Indicates the current fatigue strength, represents the initial fatigue strength; The idle aging factor The specific expression is as follows: in, Indicates idle years, Represents the idle aging factor.

6. A method for detecting rotor broken bars and thin bars faults according to claim 1, characterized in that: In step S4, the first fault risk coefficient calculated in step S3 is and the second failure risk factor The comprehensive calculation finally obtains the comprehensive failure risk coefficient The specific expression is as follows: in, and Respectively represent two weight coefficients whose sum is 1; In step S5, based on the comprehensive failure risk coefficient The specific process of judging whether to execute the fault warning instruction is as follows: When the comprehensive failure risk factor The first comprehensive risk threshold When the fault warning instruction is not executed; When the first comprehensive risk threshold Comprehensive failure risk factor The second comprehensive risk threshold When the rotor thin strip fault warning is executed; When the comprehensive failure risk factor The second comprehensive risk threshold When the rotor bar broken fault warning is executed.

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