CN115753913A - Method, device, equipment and medium for determining moisture degradation of motor stator bar - Google Patents
Method, device, equipment and medium for determining moisture degradation of motor stator bar Download PDFInfo
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Abstract
The embodiment of the invention discloses a method, a device, equipment and a medium for determining the moisture degradation of a stator bar of a motor. The method comprises the following steps: responding to an abnormal shutdown instruction of a target motor, acquiring a target stator bar of the target motor, and acquiring a test bar; carrying out at least one target test on the test wire rod to obtain each target test result; wherein the target test comprises at least one of: measuring dielectric loss factor, polarization index and depolarization current; the target test result includes at least one of: dielectric loss factor, polarization index, and depolarization index; determining a target stator bar wet degradation of the target motor when each target test result satisfies a wet degradation condition. According to the scheme of the embodiment of the invention, whether the insulation structure of the stator bar is degraded due to moisture can be accurately determined.
Description
Technical Field
The embodiment of the invention relates to the technical field of judgment on the moisture degradation of an insulation structure of a stator bar, in particular to a method, a device, equipment and a medium for determining the moisture degradation of a stator bar of a motor.
Background
The insulating structure of the stator bar of the pumped storage generator motor always bears the effects of electric stress, thermal stress, thermomechanical stress and environmental stress in the operation process, wherein the environmental stress mainly refers to humid deterioration stress, and is caused by high-temperature and high-humidity environments of a hydropower station and special conditions (such as water immersion), the insulating structure of the stator bar is subjected to moisture absorption and layered deterioration for a long time, and in severe cases, grounding accidents are caused, so that the safe operation of a unit is threatened.
For the evaluation of the electrical stress and the thermal stress degradation of the insulation structure of the stator bar, corresponding national standards and industrial standards such as GB/T17948.4 rotating electrical machines, insulation structure functional evaluation, forming winding test regulation, voltage durability evaluation and NB/T42004 high-voltage alternating current motor stator coil to ground insulation electrical aging test methods are established domestically; because the running temperature of the stator windings of the hydro-generator and the pumped storage generator motor is usually not more than 120 ℃, the thermal stress is not the main degradation type of the generator, the test is usually not specially carried out for the thermal stress, but the electrical stress and the thermal stress are comprehensively considered as multi-factor degradation factors, and the execution standard is GB/T17948.5 rotating electrical machine-insulating structure functionality evaluation-formed winding test procedure-thermal and electrical comprehensive stress durability multi-factor evaluation; the thermomechanical deterioration is a typical insulation deterioration mode of a pumped storage generator motor, and is partially determined by reference to a standard GB/T17948.6 rotating electrical machine-insulation structure functional evaluation-forming winding test procedure-insulation structure thermomechanical durability evaluation. Aiming at the evaluation of the moisture degradation of the insulation structure, at present, no unified test method and degradation criterion indexes are established at home and abroad.
How to accurately determine whether a stator bar insulation structure is degraded due to moisture through a test method is a key issue of research in the industry.
Disclosure of Invention
The embodiment of the invention provides a method, a device, equipment and a medium for determining the moisture degradation of a stator bar of a motor, which are used for accurately determining whether the insulation structure of the stator bar is degraded due to moisture.
According to an aspect of an embodiment of the present invention there is provided a method of determining wet deterioration of a stator bar of an electric motor, comprising:
responding to an abnormal stop command of a target motor, acquiring a target stator bar of the target motor, and acquiring a test bar;
performing at least one target test on the test wire rod to obtain each target test result; wherein the target test comprises at least one of: measuring dielectric loss factor, polarization index and depolarization current; the target test result includes at least one of: dielectric loss factor, polarization index, and depolarization index;
determining a target stator bar wet degradation of the target motor when each target test result satisfies a wet degradation condition.
According to another aspect of an embodiment of the present invention there is provided a device for determining wet deterioration of a stator bar of an electric motor, comprising:
the test bar acquisition module is used for responding to an abnormal shutdown instruction of a target motor, acquiring a target stator bar of the target motor and obtaining a test bar;
the target test result determining module is used for carrying out at least one target test on the test wire rod to obtain each target test result; wherein the target test comprises at least one of: measuring dielectric loss factor, polarization index and depolarization current; the target test result includes at least one of: dielectric loss factor, polarization index, and depolarization index;
a wet degradation determination module to determine a target stator bar wet degradation of the target motor when each target test result satisfies a wet degradation condition.
According to another aspect of the embodiments of the present invention, there is provided an electronic apparatus, including:
at least one processor; and
a memory communicatively coupled to the at least one processor; wherein the content of the first and second substances,
the memory stores a computer program executable by the at least one processor to enable the at least one processor to perform a method of determining wet deterioration of motor stator bars as described in any of the embodiments of the invention.
According to another aspect of embodiments of the present invention, there is provided a computer readable storage medium having stored thereon computer instructions for causing a processor to carry out a method of determining wet deterioration of motor stator bars according to any one of the embodiments of the present invention.
According to the technical scheme of the embodiment of the invention, a target stator bar of a target motor is obtained by responding to an abnormal halt instruction of the target motor, and a test bar is obtained; carrying out at least one target test on the test wire rod to obtain each target test result; wherein the target test comprises at least one of: measuring dielectric loss factor, polarization index and depolarization current; the target test result includes at least one of: dielectric loss factor, polarization index, and depolarization index; when each target test result meets the moisture degradation condition, the target stator bar moisture degradation of the target motor is determined, and whether the insulation structure of the stator bar is moisture degradation or not can be accurately determined.
It should be understood that the statements in this section do not necessarily identify key or critical features of any embodiments of the present invention, nor limit the scope of any embodiments of the present invention. Other features of embodiments of the present invention will become apparent from the following description.
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In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.
FIG. 1 is a flow chart of a method of determining wet degradation of a stator bar of an electric motor according to one embodiment of the present invention;
FIG. 2 is a fragmentary schematic view of a target stator bar provided in accordance with a first embodiment of the present invention;
FIG. 3 is a flow chart of a method of determining wet degradation of a stator bar of an electric motor according to a second embodiment of the present invention;
FIG. 4 is a schematic wiring diagram of an electrode structure for dielectric loss tangent measurement according to a second embodiment of the present invention;
FIG. 5 is a schematic wiring diagram of an electrode structure for polarization index measurement and depolarization current index measurement according to a second embodiment of the invention;
FIG. 6 is a schematic structural view of a device for determining the wet deterioration of a stator bar of an electric motor according to a third embodiment of the present invention;
figure 7 is a schematic structural diagram of electronic equipment implementing a method of determining wet degradation of a motor stator bar in accordance with an embodiment of the invention.
Detailed Description
In order to make those skilled in the art better understand the embodiments of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments, not all embodiments, of the embodiments of the present invention. All other embodiments obtained by persons of ordinary skill in the art based on the embodiments of the present invention without any creative efforts shall fall within the protection scope of the embodiments of the present invention.
It should be noted that the terms "first," "second," and the like in the description and claims of the embodiments of the present invention and in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the invention described herein are capable of operation in sequences other than those illustrated or described herein. Moreover, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.
Example one
Fig. 1 is a flow chart of a method for determining the moisture deterioration of a stator bar of an electric motor according to an embodiment of the present invention, which can be applied to accurately determine whether a stator bar insulation structure is in a moisture deterioration condition by a test method, and the method can be executed by a device for determining the moisture deterioration of a stator bar of an electric motor, which can be implemented in hardware and/or software, and can be configured in an electronic device such as a computer, a server or a tablet computer. Specifically, referring to fig. 1, the method specifically includes the following steps:
The target motor may be any generator motor in the pumped storage group, which is not limited in this embodiment. The target stator bar of the target motor may be any one of the stator bars of the target motor, which is also not limited in the present embodiment.
In an optional implementation manner of the embodiment, if sudden shutdown of the target motor is detected, namely abnormal shutdown, a target stator bar of the target motor can be obtained, and then a test bar is obtained according to interception of the target stator bar.
Optionally, in this embodiment, obtaining a target stator bar of the target motor and obtaining a test bar may include: and moving the target electronic bar out of the iron core slot, reserving a stator bar straight line part in the iron core length range of the target stator bar slot part, and removing the low-resistance anti-corona layer of the target stator bar to obtain the test bar.
It should be noted that the stator bar used by the operation unit of the pumped storage hydropower station is a finished bar, and a permanent low-resistance (anti-corona) layer (region) of a slot part and a high-resistance (anti-corona) layer (region) at the end part are already formed; fig. 2 is a schematic cut-out view of a target stator bar according to an embodiment of the present invention, as shown in fig. 2, after a pumped storage generator-motor unit employing a low-glue VPI (Vacuum Pressure impregnation) stator bar insulation structure is stopped, the stator bar to be evaluated is removed from an iron core slot, surface attachments are removed, the stator bar is placed on a dry insulation support frame, a stator bar straight portion within a slot iron core length range of the stator bar is reserved, and two end portions (portions outside the slot iron core length range) of the bar are cut off; cutting off an insulating layer with the width of 20mm from one end of the straight line part of the intercepted wire rod, taking an exposed copper conductor as a high-voltage electrode, then respectively removing low-resistance anti-corona layers with the width of 200mm from the insulating tail ends of two sides of the wire rod along the surface, wiping the surface of the wire rod by using absolute ethyl alcohol after the cutting operation is finished, removing surface dirt, wrapping an aluminum foil electrode on the surface of the low-resistance anti-corona layers of the wire rod as a measuring electrode, and tightening the whole measuring electrode by using a scrubbing wave band from a middle part (usually a bare copper wire); aluminum foil electrodes with the width of 10mm are respectively pasted at the positions 10mm away from the tail end of the low-resistance anti-corona layer on the two sides of the wire rod to serve as protective electrodes.
And 120, performing at least one target test on the test wire rod to obtain each target test result.
Wherein the target test comprises at least one of: measuring dielectric loss factor, polarization index and depolarization current; the target test result includes at least one of: dielectric loss factor, polarization index, and depolarization index.
In an optional implementation manner of the embodiment, after the test bar is intercepted, at least one target test can be further performed on the test bar, so that a target test result is obtained; illustratively, the dielectric loss factor, the polarization index and the depolarization current of the test bar can be measured respectively, so as to obtain the dielectric loss factor, the polarization index and the depolarization index.
Optionally, in this embodiment, the dielectric loss tangent measurement, the polarization index measurement, and the depolarization current measurement may be performed by a mechanical loss tangent tester and an insulation resistance tester.
Wherein the moisture degradation condition may comprise at least one of:
dielectric loss factor: magnitude (0.2U) N ) < magnitude (0.4U) N ) < magnitude (0.6U) N ) < magnitude (0.8U) N ) < magnitude (1.0U) N ) < magnitude (1.2U) N ) (ii) a Polarization index:
and, depolarization index:
wherein, U N Is the rated line voltage.
In an alternative implementation of this embodiment, after obtaining the target test results, the target test results may be compared with the moisture degradation conditions in sequence, and when the target test results satisfy the moisture degradation conditions, the target stator bar moisture degradation of the target motor may be determined.
Illustratively, in this embodiment, if tested, it is determined thatThe dielectric loss factor of the obtained dielectric layer satisfies the magnitude (0.2U) N ) < magnitude (0.4U) N ) < magnitude (0.6U) N ) < magnitude (0.8U) N ) < magnitude (1.0U) N ) < magnitude (1.2U) N ) (ii) a The index of polarization satisfies
And, depolarization index satisfies
A determination can be made of the target stator bar wet degradation of the target motor.
According to the technical scheme of the embodiment, a target stator bar of a target motor is obtained by responding to an abnormal shutdown command of the target motor, and a test bar is obtained; carrying out at least one target test on the test wire rod to obtain each target test result; when each target test result meets the moisture degradation condition, the target stator bar moisture degradation of the target motor is determined, and whether the insulation structure of the stator bar is moisture degradation or not can be accurately determined.
Example two
Fig. 3 is a flowchart of a method for determining wet deterioration of a stator bar of an electric motor according to a second embodiment of the present invention, which is a further refinement of the above-mentioned solutions, and the solutions in the present embodiment can be combined with various alternatives in one or more of the above-mentioned embodiments. As shown in fig. 3, a method of determining wet degradation of a motor stator bar may include the steps of:
And 320, performing at least one target test on the test bar to obtain each target test result.
Wherein the target test comprises at least one of: measuring dielectric loss factor, polarization index and depolarization current; the target test result includes at least one of: dielectric loss factor, polarization index, and depolarization index.
In an optional implementation manner of this embodiment, after the test bar is obtained by cutting, the cut test bar may be further subjected to dielectric loss factor measurement, polarization index measurement, and depolarization current measurement, respectively, to obtain a dielectric loss factor, a polarization index, and a depolarization index.
Optionally, in this embodiment, the performing the dielectric loss factor measurement, the polarization index measurement, and the depolarization current measurement on the test bar respectively may include: measuring the dielectric loss factor of the test wire rod by a dielectric loss factor tester; polarization index measurements and depolarization index measurements were made by an insulation resistance tester.
In an optional implementation manner of this embodiment, the measuring the dielectric loss factor of the test bar by the dielectric loss factor tester may include: respectively setting the line voltages of the dielectric loss factor tester to be 0.2U N 、0.4U N 、0.6U N 、0.8U N 、1.0U N And 1.2U N Connecting the high-voltage pole of the test bar to a high-voltage end, connecting the measuring pole of the test bar to a low-voltage measuring end of a dielectric loss factor tester, and grounding the protective pole of the test bar to form a positive wiring and three-electrode measuring system; wherein, U N Is the rated line voltage.
FIG. 4 is a schematic wiring diagram of an electrode structure for dielectric loss tangent measurement according to a second embodiment of the present invention; as shown in FIG. 4, at 0.2U respectively N 、0.4U N 、0.6U N 、0.8U N 、1.0U N 、1.2U N Conducting a dielectric loss factor test in which U N For rated line voltage, the high-voltage pole of the test bar is connected to a high-voltage end (generally, the high-voltage output end of a power frequency test transformer which can output the requirement of meeting GB/T169927.1 and has no partial discharge), the measuring pole of the test bar is connected to a low-voltage measuring end of a dielectric loss factor tester, and the protective pole of the test bar is grounded to form a positive wiring and three-electrode measuring system.
Further, the measurement of the polarization index and the measurement of the depolarization index by the insulation resistance tester may include: measuring insulation resistance and polarization index by an insulation resistance tester with direct current 2500V, connecting a high-voltage pole of the test bar to a direct-current high-voltage end of the insulation resistance tester, connecting a measurement pole of the test bar to a low-voltage end of the insulation resistance tester and grounding, and grounding a protection pole of the test bar; and carrying out polarization depolarization current measurement under the voltage of direct current 500V, connecting the high-voltage pole of the test bar to the direct-current high-voltage end of the insulation resistance tester, connecting the measurement pole of the test bar to the low-voltage end of the insulation resistance tester and grounding, and grounding the protection pole of the test bar.
FIG. 5 is a schematic wiring diagram of an electrode structure for polarization index measurement and depolarization current index measurement according to a second embodiment of the present invention; as shown in fig. 5, an insulation resistance tester of 2500V dc can be selected to measure the insulation resistance and polarization index, the high voltage terminal of the test bar is connected to the high voltage dc terminal of the insulation resistance tester, the measurement terminal of the test bar is connected to the low voltage terminal of the insulation resistance tester and grounded, the protection terminal of the test bar is grounded, the selected electrode structure is different from the two electrode structures commonly used, the insulation resistance values of 1 minute and 10 minutes are measured for a shielded electrode structure, and the polarization index can be obtained by calculation or direct reading according to the difference of the functions of the tester.
Further, polarization depolarization current measurement can be performed under a direct current voltage of 500V, the basic measurement connection is the same as that in fig. 5, KEITHLEY 6487 type picoammeter/Iris DRA iii measurement equipment is taken as an example to explain a depolarization current measurement process, a high-voltage pole of a test bar is connected to a direct current high-voltage end of the measurement equipment, a measurement pole of the test bar is connected to a low-voltage end of the measurement equipment and is grounded, a protection pole of the test bar is grounded, the measurement process includes polarization current measurement and depolarization current measurement, polarization current measurement time is set to be 10 minutes, depolarization current measurement time is set to be 10 minutes, and after the polarization current measurement is completed, the depolarization current measurement is immediately performed under the condition of no holding time, and depolarization current values of 1 second, 10 seconds, 1 minute and 10 minutes are read; when the polarized current is measured, the direct-current high voltage is connected into the circuit, the current value is manually/automatically read through the built-in skin safety meter, after the specified time is reached, the built-in switch is switched off, the high voltage is removed, the measuring circuit is reversely connected, the depolarization current is measured, and the reverse current is manually/automatically measured through the built-in skin safety meter. It should be noted that, since the selected high voltage value (500V) is relatively low, it is not necessary to start the high voltage circuit breaker, and thus the holding time may not be set.
In an optional implementation manner of the embodiment, the measured dielectric loss factor, polarization index and depolarization index respectively satisfy the magnitude (0.2U) N ) < magnitude (0.4U) N ) < magnitude (0.6U) N ) < magnitude (0.8U) N ) < magnitude (1.0U) N ) < magnitude (1.2U) N )、
And the number of the first and second groups,
a target stator bar wet degradation is determined.
It should be noted that stator bar thermomechanical stress degradation and moisture (stress) degradation are the most common degradation types of pumped storage generator motor stator bars, and since thermomechanical degradation will cause delamination between the stator bar copper conductor and the main insulation, the dielectric loss factor will exhibit characteristic variation characteristics: magnitude (0.2U) N ) < magnitude (0.4U) N ) < magnitude (0.6U) N ) Magnitude (1.2U) N ) < magnitude (1.0U) N ) < magnitude (0.8U) N ) < magnitude (0.6U) N ) This is inconsistent with the determination regarding dielectric loss tangent in the embodiments of the present invention, and thus the thermo-mechanical deterioration of the insulation structure can be distinguished by the determination regarding dielectric loss tangent in the present invention.
Meanwhile, the measurement of insulation resistance and polarization index is a commonly used means for judging the degradation of the insulation structure of the stator bar, wherein the insulation resistance is an important means for judging breakdown, and the polarization index is related to the moisture degradation, surface conductivity pollution and anti-corona structure of the insulation structure and is insensitive to the characteristic expression of electrical stress degradation, and the judgment of the intercepted stator bar is specified in the invention, so that the influence of a double-layer anti-corona structure (anti-corona coat structure) on the measurement result is fundamentally avoided (for the bar of which the outer high-resistance anti-corona layer is finished at the tail end of a copper conductor, the polarization index can be close to 1 under the condition of no degradation);
the measurement of the polarization current and the depolarization current can visually display the change conditions of the charging current and the discharging current, the measured total current consists of surface leakage current, conductive current, capacitance current and absorption current under the condition of externally applied direct current voltage (step voltage, 500V), after the externally applied direct current voltage is removed, the measured total current consists of the capacitance current and the absorption current, the polarization index measurement and the depolarization current measurement are not influenced due to the extremely fast attenuation of the capacitance current (no more than 0.5 second), the depolarization index is a ratio of the polarization currents at two different times, the residual current is only absorption (polarization discharge) current due to the fact that high voltage is removed, the measurement unit does not comprise a high-resistance wire rod anti-corona area and adopts a shielding electrode structure, the influence of anti-corona interlayer polarization caused by different conductivities is eliminated, the interface polarization (polarization effect after water absorption) is dominant, and the depolarization index becomes a characteristic parameter for judging the moisture degradation, and the judgment index of the polarization index is determined by combining the field operation condition and the moisture working condition in a test room.
The copper hammer strikes the surface of the wire rod, the insulation state is judged by using the 'ears' which is a common means for judging the insulation degradation state, data are transmitted to a computer system by using a sound acquisition and analysis system while striking, and Fourier analysis is carried out on the data to obtain an auxiliary characteristic criterion of moisture degradation; knocking the surface of a bar by using a solid copper hammer, simultaneously installing a B & K acoustic sensor near a detected part, knocking a main insulator to generate frequency response, transmitting a measured acoustic response signal to a B & K-1704 acoustic amplifier, setting amplification gain according to a field noise environment, transmitting the amplified acoustic signal to an NI-9185 data acquisition and analysis system, transmitting data to a computer through an industrial Ethernet, performing Fourier transform on the signal, and taking pulses with amplitude being more than 10 times of background noise level as auxiliary criteria within a frequency range of 8000Hz +/-2000 Hz for 1 time or more; the secondary criterion does not affect the decision result of the primary criterion.
In an alternative implementation of the embodiment, after determining the target stator bar wet degradation of the target motor, a replacement instruction of the target stator bar of the target motor may be further sent to a serviceman (e.g., to a terminal held by the serviceman) so as to replace the target stator bar in time, and avoid affecting normal power generation of the target motor due to the wet degradation of the target stator bar.
According to the scheme of the embodiment, after the target stator bar of the target motor is determined to be degraded due to moisture, a replacement instruction of the target stator bar of the target motor can be further sent to a maintenance worker, so that the target stator bar can be replaced timely, and normal power generation of the target motor is prevented from being influenced due to the degraded due to moisture of the target stator bar.
EXAMPLE III
Fig. 6 is a schematic structural diagram of a device for determining the moisture degradation of the stator bars of the motor according to the third embodiment of the invention. As shown in fig. 6, the apparatus includes: a test bar acquisition module 610, a target test result determination module 620, and a moisture degradation determination module 630.
A test bar acquisition module 610, configured to respond to an abnormal shutdown instruction of a target motor, acquire a target stator bar of the target motor, and obtain a test bar;
a target test result determining module 620, configured to perform at least one target test on the test wire rod to obtain each target test result; wherein the target test comprises at least one of: measuring dielectric loss factor, polarization index and depolarization current; the target test result includes at least one of: dielectric loss factor, polarization index, and depolarization index;
a wet degradation determination module 630 for determining a target stator bar wet degradation of the target motor when each target test result satisfies a wet degradation condition.
According to the scheme of the embodiment, a test bar acquisition module responds to an abnormal shutdown instruction of a target motor to acquire a target stator bar of the target motor and obtain a test bar; performing at least one target test on the test wire rod through a target test result determining module to obtain each target test result; by determining a target stator bar wet degradation of the target motor by a wet degradation determination module, it can be accurately determined whether a stator bar insulation structure is wet degraded.
In an optional implementation manner of this embodiment, the test bar obtaining module 610 is specifically configured to move the target electronic bar out of the core slot, retain a stator bar straight portion in a core length range of the target stator bar slot portion, and remove a low resistance anti-corona layer of the target stator bar to obtain the test bar.
In an optional implementation manner of this embodiment, the target test result determining module 620 is specifically configured to perform dielectric loss factor measurement, polarization index measurement, and depolarization current measurement on the test bar, respectively, to obtain a dielectric loss factor, a polarization index, and a depolarization index.
In an optional implementation manner of this embodiment, the target test result determining module 620 is further specifically configured to perform dielectric loss factor measurement on the test bar through a dielectric loss factor tester; polarization index measurement and depolarization index measurement were performed by an insulation resistance tester.
In an optional implementation manner of this embodiment, the target test result determining module 620 is further specifically configured to set the line voltages of the dielectric loss factor testers to 0.2U respectively N 、0.4U N 、0.6U N 、0.8U N 、1.0U N And 1.2U N Connecting the high-voltage pole of the test bar to a high-voltage end, connecting the measuring pole of the test bar to a low-voltage measuring end of a dielectric loss factor tester, and grounding the protective pole of the test bar to form a positive wiring and three-electrode measuring system; wherein, U N Is rated line voltage;
measuring insulation resistance and polarization index by an insulation resistance tester with direct current 2500V, connecting a high-voltage pole of the test bar to a direct-current high-voltage end of the insulation resistance tester, connecting a measurement pole of the test bar to a low-voltage end of the insulation resistance tester and grounding, and grounding a protection pole of the test bar;
and carrying out polarization depolarization current measurement under the voltage of direct current 500V, connecting the high-voltage pole of the test bar to the direct-current high-voltage end of the insulation resistance tester, connecting the measurement pole of the test bar to the low-voltage end of the insulation resistance tester and grounding, and grounding the protection pole of the test bar.
In an optional implementation of this embodiment, the moisture degradation condition includes at least one of:
dielectric loss factor: magnitude (0.2U) N ) < magnitude (0.4U) N ) < magnitude (0.6U) N ) < magnitude (0.8U) N ) < magnitude (1.0U) N ) < magnitude (1.2U) N )；
Polarization index:
and, depolarization index:
in an alternative implementation of this embodiment, the means for determining wet degradation of the stator bars of the electric motor further comprises: a replacement command sending module for sending a replacement command of a target stator bar of a target motor to a serviceman and replacing the target stator bar of the target motor at that time.
The device for determining the moisture deterioration of the motor stator bar provided by the embodiment of the invention can execute the method for determining the moisture deterioration of the motor stator bar provided by any embodiment of the invention, and has corresponding functional modules and beneficial effects of the execution method.
Example four
FIG. 7 illustrates a schematic structural diagram of an electronic device 10 that may be used to implement embodiments of the present invention. Electronic devices are intended to represent various forms of digital computers, such as laptops, desktops, workstations, personal digital assistants, servers, blade servers, mainframes, and other appropriate computers. The electronic device may also represent various forms of mobile devices, such as personal digital assistants, cellular phones, smart phones, wearable devices (e.g., helmets, glasses, watches, etc.), and other similar computing devices. The components shown herein, their connections and relationships, and their functions, are meant to be exemplary only, and are not meant to limit implementations of embodiments of the inventions described and/or claimed herein.
As shown in fig. 7, the electronic device 10 includes at least one processor 11, and a memory communicatively connected to the at least one processor 11, such as a Read Only Memory (ROM) 12, a Random Access Memory (RAM) 13, and the like, wherein the memory stores a computer program executable by the at least one processor, and the processor 11 may perform various appropriate actions and processes according to the computer program stored in the Read Only Memory (ROM) 12 or the computer program loaded from the storage unit 18 into the Random Access Memory (RAM) 13. In the RAM 13, various programs and data necessary for the operation of the electronic apparatus 10 can also be stored. The processor 11, the ROM 12, and the RAM 13 are connected to each other via a bus 14. An input/output (I/O) interface 15 is also connected to bus 14.
A number of components in the electronic device 10 are connected to the I/O interface 15, including: an input unit 16 such as a keyboard, a mouse, or the like; an output unit 17 such as various types of displays, speakers, and the like; a storage unit 18 such as a magnetic disk, optical disk, or the like; and a communication unit 19 such as a network card, modem, wireless communication transceiver, etc. The communication unit 19 allows the electronic device 10 to exchange information/data with other devices via a computer network such as the internet and/or various telecommunication networks.
The processor 11 may be a variety of general and/or special purpose processing components having processing and computing capabilities. Some examples of processor 11 include, but are not limited to, a Central Processing Unit (CPU), a Graphics Processing Unit (GPU), various dedicated Artificial Intelligence (AI) computing chips, various processors running machine learning model algorithms, a Digital Signal Processor (DSP), and any suitable processor, controller, microcontroller, and so forth. The processor 11 performs the various methods and processes described above, such as the method of determining wet deterioration of the motor stator bars.
In some embodiments, the method of determining wet degradation of a motor stator bar may be implemented as a computer program tangibly embodied on a computer readable storage medium, such as the storage unit 18. In some embodiments, part or all of the computer program may be loaded and/or installed onto the electronic device 10 via the ROM 12 and/or the communication unit 19. When the computer program is loaded into RAM 13 and executed by processor 11, one or more steps of the method of determining wet deterioration of a motor stator bar described above may be performed. Alternatively, in other embodiments, the processor 11 may be configured to perform the method of determining wet deterioration of the motor stator bars by any other suitable means (e.g. by means of firmware).
Various implementations of the systems and techniques described here above may be implemented in digital electronic circuitry, integrated circuitry, field Programmable Gate Arrays (FPGAs), application Specific Integrated Circuits (ASICs), application Specific Standard Products (ASSPs), system on a chip (SOCs), load programmable logic devices (CPLDs), computer hardware, firmware, software, and/or combinations thereof. These various embodiments may include: implemented in one or more computer programs that are executable and/or interpretable on a programmable system including at least one programmable processor, which may be special or general purpose, receiving data and instructions from, and transmitting data and instructions to, a storage system, at least one input device, and at least one output device.
Computer programs for implementing methods of embodiments of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus, such that the computer programs, when executed by the processor, cause the functions/acts specified in the flowchart and/or block diagram block or blocks to be performed. A computer program can execute entirely on a machine, partly on a machine, as a stand-alone software package partly on a machine and partly on a remote machine or entirely on a remote machine or server.
In the context of embodiments of the present invention, a computer-readable storage medium may be a tangible medium that can contain, or store a computer program for use by or in connection with an instruction execution system, apparatus, or device. A computer readable storage medium may include, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. Alternatively, the computer readable storage medium may be a machine readable signal medium. More specific examples of a machine-readable storage medium would include an electrical connection based on one or more wires, a portable computer diskette, a hard disk, a Random Access Memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.
To provide for interaction with a user, the systems and techniques described here can be implemented on an electronic device having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to a user; and a keyboard and a pointing device (e.g., a mouse or a trackball) by which a user may provide input to the electronic device. Other kinds of devices may also be used to provide for interaction with a user; for example, feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user may be received in any form, including acoustic, speech, or tactile input.
The systems and techniques described here can be implemented in a computing system that includes a back-end component (e.g., as a data server), or that includes a middleware component (e.g., an application server), or that includes a front-end component (e.g., a user computer having a graphical user interface or a web browser through which a user can interact with an implementation of the systems and techniques described here), or any combination of such back-end, middleware, or front-end components. The components of the system can be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include: local Area Networks (LANs), wide Area Networks (WANs), blockchain networks, and the Internet.
The computing system may include clients and servers. A client and server are generally remote from each other and typically interact through a communication network. The relationship of client and server arises by virtue of computer programs running on the respective computers and having a client-server relationship to each other. The server can be a cloud server, also called a cloud computing server or a cloud host, and is a host product in a cloud computing service system, so that the defects of high management difficulty and weak service expansibility in the traditional physical host and VPS service are overcome.
It should be understood that various forms of the flows shown above, reordering, adding or deleting steps, may be used. For example, the steps described in the embodiments of the present invention may be executed in parallel, may be executed sequentially, or may be executed in different orders, as long as the desired result of the technical solution of the embodiments of the present invention can be achieved, which is not limited herein.
The above detailed description does not limit the scope of the embodiments of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions may be made in accordance with design requirements and other factors. Any modification, equivalent replacement, and improvement made within the spirit and principle of the embodiments of the present invention should be included in the scope of the embodiments of the present invention.
Claims (10)
1. A method of determining wet degradation of a stator bar of an electric motor, comprising:
responding to an abnormal stop command of a target motor, acquiring a target stator bar of the target motor, and acquiring a test bar;
performing at least one target test on the test wire rod to obtain each target test result; wherein the target test comprises at least one of: measuring dielectric loss factor, polarization index and depolarization current; the target test result includes at least one of: dielectric loss factor, polarization index, and depolarization index;
determining a target stator bar wet degradation of the target motor when each target test result satisfies a wet degradation condition.
2. The method of claim 1, wherein said obtaining a target stator bar of said target motor and obtaining a trial bar comprises:
and moving the target electronic bar out of the iron core slot, reserving a stator bar straight line part in the iron core length range of the target stator bar slot part, and removing the low-resistance anti-corona layer of the target stator bar to obtain the test bar.
3. The method of claim 1, wherein said performing at least one target test on said test bar to obtain target test results comprises:
and respectively measuring the dielectric loss factor, the polarization index and the depolarization current of the test wire rod to obtain the dielectric loss factor, the polarization index and the depolarization index.
4. The method of claim 3, wherein said making dielectric loss factor measurements, polarization index measurements, and depolarization current measurements of said test bars, respectively, comprises:
measuring the dielectric loss factor of the test wire rod by a dielectric loss factor tester;
polarization index measurements and depolarization index measurements were made by an insulation resistance tester.
5. The method of claim 4, wherein said making a dielectric loss factor measurement of said test bar by a dielectric loss factor tester comprises:
respectively setting the line voltages of the dielectric loss factor tester to be 0.2U N 、0.4U N 、0.6U N 、0.8U N 、1.0U N And 1.2U N Connecting the high-voltage pole of the test bar to a high-voltage end, connecting the measuring pole of the test bar to a low-voltage measuring end of a dielectric loss factor tester, and grounding the protective pole of the test bar to form a positive wiring and three-electrode measuring system; wherein, U N Is rated line voltage;
the polarization index measurement and depolarization index measurement by the insulation resistance tester include:
measuring insulation resistance and polarization index by an insulation resistance tester with direct current 2500V, connecting a high-voltage pole of the test bar to a direct-current high-voltage end of the insulation resistance tester, connecting a measurement pole of the test bar to a low-voltage end of the insulation resistance tester and grounding, and grounding a protection pole of the test bar;
and carrying out polarization depolarization current measurement under the voltage of direct current 500V, connecting the high-voltage pole of the test bar to the direct-current high-voltage end of the insulation resistance tester, connecting the measurement pole of the test bar to the low-voltage end of the insulation resistance tester and grounding, and grounding the protection pole of the test bar.
6. The method according to any one of claims 1-5, wherein the humid degradation condition comprises at least one of:
dielectric loss factor: magnitude (0.2U) N ) < magnitude (0.4U) N ) < magnitude (0.6U) N ) < magnitude (0.8U) N ) < magnitude (1.0U) N ) < magnitude (1.2U) N )；
Polarization index:
and, depolarization index:
7. the method of claim 1, after determining a target stator bar wet degradation of the target motor, further comprising:
sending a replacement instruction of a target stator bar of a target motor to a serviceman, and replacing the target stator bar of the target motor at that time.
8. An apparatus for determining wet degradation of a stator bar of an electric motor, comprising:
the test bar acquisition module is used for responding to an abnormal shutdown instruction of a target motor, acquiring a target stator bar of the target motor and obtaining a test bar;
the target test result determining module is used for carrying out at least one target test on the test wire rod to obtain each target test result; wherein the target test comprises at least one of: measuring dielectric loss factor, polarization index and depolarization current; the target test result includes at least one of: dielectric loss factor, polarization index, and depolarization index;
a wet degradation determination module to determine a target stator bar wet degradation of the target motor when each target test result satisfies a wet degradation condition.
9. An electronic device, characterized in that the electronic device comprises:
at least one processor; and
a memory communicatively coupled to the at least one processor; wherein the content of the first and second substances,
the memory stores a computer program executable by the at least one processor to enable the at least one processor to perform the method of determining wet degradation of motor stator bars as claimed in any one of claims 1 to 7.
10. A computer readable storage medium having stored thereon computer instructions for causing a processor to carry out a method of determining wet deterioration of a motor stator bar as claimed in any one of claims 1 to 7 when executed.
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