CN108008296A - A kind of double-fed asynchronous generator hot-spot method for diagnosing faults - Google Patents

A kind of double-fed asynchronous generator hot-spot method for diagnosing faults Download PDF

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Publication number
CN108008296A
CN108008296A CN201711210361.9A CN201711210361A CN108008296A CN 108008296 A CN108008296 A CN 108008296A CN 201711210361 A CN201711210361 A CN 201711210361A CN 108008296 A CN108008296 A CN 108008296A
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China
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double
fed asynchronous
asynchronous generator
hot
vibration signal
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CN201711210361.9A
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Chinese (zh)
Inventor
马宏忠
李思源
张艳
刘宝稳
徐艳
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Hohai University HHU
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Hohai University HHU
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Priority to CN201711210361.9A priority Critical patent/CN108008296A/en
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/34—Testing dynamo-electric machines
    • G01R31/343—Testing dynamo-electric machines in operation

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Tests Of Circuit Breakers, Generators, And Electric Motors (AREA)

Abstract

The invention discloses a kind of double-fed asynchronous generator hot-spot method for diagnosing faults, it is first depending on electric brush slip ring system vibration method principle, Vibration propagation approach disposes vibrating sensor on laboratory double-fed asynchronous generator electric brush slip ring surface, vibration signal when real-time induction system is run；Then vibration signal that each vibrating sensor detects is gathered by data collecting instrument and is sent to host computer；Vibration signal is stored last host computer and calculating processing, and the judgement and positioning of failure are carried out using 937.5Hz 1562.5Hz signals in vibration signal.Method for diagnosing faults accurate and effective of the present invention, diagnosis accuracy are high.

Description

A kind of double-fed asynchronous generator hot-spot method for diagnosing faults
Technical field
The present invention relates to a kind of double-fed asynchronous generator hot-spot method for diagnosing faults, belongs to driving motor status detection With fault diagnosis technology field.
Background technology
Electric brush slip ring system is the important sound conversion equipment of large-scale dual-feed asynchronous wind power generator, to the stabilization of generator Operation plays a crucial role.But the generator operation caused by slip-ring device hot-spot failure is unstable existing As occurring repeatedly, huge economic loss is caused.So the hot-spot diagnostic method research to motor sliding ring device is not allowed at quarter It is slow.
The reason for causing slip ring hot-spot failure in real work is mainly as follows：Since dual-feed asynchronous wind power generator is slided Ring surface is uniform-distribution with many brushes, between electric brush slip ring the change of contact resistance will cause the uneven distribution of brush current, So as to cause brush fever abnormal, cause overheat；When the electric brush slip ring system failure is run, the friction factor change of slip ring surface is very Greatly, rub generation heat also can therefore and increase considerably；When the blocking of generation cooling air channel, current collection ring surface air duct and lead to When air holes blocks, collector ring surface temperature can be caused excessive, brush wear aggravation, carbon dust constantly accumulates, and hinders current collection ring surface Heat distribute and slip ring surface hot-spot failure occur.
In this regard, have the transient temperature that scholar utilizes computer technology research brush, meter and Frictional Factor of Electric Brush, contact pressure The factors such as drop, size, contact, current density, derive the temperature rise formula for calculating brush.There is scholar to be embedded into thermocouple In brush away from contact surface 0.15-0.25mm depths, to measure its temperature.In addition, Non-contact Infrared Temperature Measurement technology is wide It is applied to generally in generator brush and slip ring temperature monitoring.There is scholar to use infrared temperature probe non-cpntact measurement slip ring surface Temperature, by communication bus real-time Transmission temperature data, and sets temperature alarm function.
A variety of temperature analysis method precision are not high more than considering, can't stablize at present, brush is slided precisely in real time Loop system global temperature field is reflected.Based on this, a kind of double-fed asynchronous generator slip ring based on vibration of the present invention The diagnostic method of device hot-spot failure, diagnosis accuracy is high, workable.
The content of the invention
Purpose：In order to overcome the deficiencies in the prior art, there is provided a kind of very close actual value of diagnostic result, is examined Disconnected result is effective, a kind of high, the workable double-fed asynchronous generator hot-spot method for diagnosing faults of diagnosis accuracy, bag Include following steps：
A kind of double-fed asynchronous generator hot-spot method for diagnosing faults, comprises the following steps：
Step 1：Double-fed asynchronous generator hot-spot fault diagnosis system is built, the system comprises：Translation interface is used It is mutual in vibration signal is converted into current signal, data collecting instrument, data analysis module, multiple vibrating sensors and an electric current Sensor；The vibrating sensor is arranged on inside double-fed asynchronous generator, and the current transformer is arranged on double-fed asynchronous power generation At the rotor windings of machine；
Step 2：It is 10kHz to set data collecting instrument sample frequency, and sampling number is 4000, sets double-fed asynchronous power generation The rotor windings load current of machine is the 70%~100% of rated current；
Step 3：When double-fed asynchronous generator works normally, the vibration signal of continuous acquisition multichannel vibrating sensor and turn Electron current value is each multigroup, is filtered noise reduction to the vibration signal collected by data analysis module, then time-frequency conversion obtains To the component amplitude of multigroup each each frequency spectrum of road vibration sensor signal；
Step 4：Vibration signals spectrograph is sampled to each road vibrating sensor each group respectively in 937.5Hz~1562.5Hz frequency ranges The amplitude of interior vibration signal whole component is summed, and vibrating sensor multigroup summing value in Zai Duige roads carries out average value meter Calculate, then average value is converted into, obtain each road vibrating sensor scaled value, each road vibrating sensor scaled value is multiplied by respectively Certain coefficient, obtains placing the temperature reference threshold value T of each road vibrating sensor position in double-fed asynchronous generator1i, i is vibration biography The quantity of sensor；Mean value calculation is carried out to multigroup rotor current, obtains rotor current reference value I；And in host computer PC Data analysis module memory storage temperature reference threshold value T1iWith rotor current reference value I；
Step 5：Load condition detection is carried out to the double-fed asynchronous generator of a unknown failure situation, continuous sampling is multigroup The vibration signal and rotor current of somewhere vibrating sensor, calculate 937.5Hz~1562.5Hz frequency ranges of vibration signal at this The sum of interior each component amplitude, is converted into after asking more class values average, then scaled value is multiplied by certain coefficient, and it is real to try to achieve temperature at this Survey threshold value T2i, i is the quantity of vibrating sensor；Mean value calculation is carried out to multigroup rotor current, obtains rotor current actual measurement Value I*；By temperature actual measurement threshold value T at this2iWith temperature reference threshold value T at this1iIt is divided by, obtains temperature threshold ratio value λi, i is to shake The quantity of dynamic sensor, and judge hot-spot failure whether occurs at this.
Preferably, the multiple vibrating sensor is placed on the contact position of brush and slip ring at slip ring surface, Or it is placed on brush support frame surface and slip ring and brush connectivity port position.
Preferably, the time-frequency conversion after the vibration signal filtering noise reduction uses Fourier transformation.
Preferably, spectrum component of the vibration signal at 937.5Hz~1562.5Hz frequency ranges is converted into using following formula The sum of amplitude：
Wherein, AxWhen being rotor loading situation, under any rotor current at vibration signal 937.5Hz~1562.5Hz frequency ranges The sum of each component amplitude；A937.5~1562.5It is AxScaled value；K is the ratio of rotor current reference value I and rotor current measured value I* Value.
Preferably, certain coefficient is arranged to 2.2~3.
Preferably, certain coefficient is arranged to 2.6.
Preferably, it is described to judge hot-spot failure whether occurs at this, include the following steps：
Work as λiDuring more than 2, then occurs obvious hot-spot failure at this；
Work as λiWhen between 1 and 2, then occurs slight hot-spot failure at this；
Work as λiDuring less than or equal to 1, then hot-spot failure does not occur at this.
Beneficial effect：A kind of double-fed asynchronous generator hot-spot method for diagnosing faults provided by the invention, its advantage is such as Under：
1st, it is not required to double-fed asynchronous generator and electric brush slip ring system to be separated to study respectively, ensure that motor overall structure The integrality of operation, actually detected scheme is simple and site layout project facilitates feasible, avoids the occurrence of the situation of detection of complex, improves The operability of fault diagnosis, diagnostic result are highly reliable.
2nd, conventional diagnostic method is overcome to be interfered when double-fed asynchronous generator electric brush slip ring surface is broken down The problem of factor is more, precision is not high, the specific aim of failure are stronger.
Brief description of the drawings
Fig. 1 is double-fed asynchronous generator hot-spot fault diagnosis system structure diagram；
Fig. 2 is that the present invention simulates double-fed asynchronous wind turbine electric brush slip ring system vibration sensor placement location schematic diagram；
Fig. 3 is that hot-spot fault vibration signal power spectrogram does not occur for No. 1 point position；
Fig. 4 is that hot-spot fault vibration signal power spectrogram occurs for No. 1 point position.
Embodiment
The present invention is further described below in conjunction with the accompanying drawings.
A kind of double-fed asynchronous generator hot-spot method for diagnosing faults, comprises the following steps：
Step 1：Double-fed asynchronous generator hot-spot fault diagnosis system is built, the system comprises：Translation interface is used It is mutual in vibration signal is converted into current signal, data collecting instrument, data analysis module, eight vibrating sensors and an electric current Sensor；The vibrating sensor is arranged on inside double-fed asynchronous generator, and the current transformer is arranged on double-fed asynchronous power generation At the rotor windings of machine.
Step 2：It is 10kHz to set data collecting instrument sample frequency, and sampling number is 4000, sets double-fed asynchronous power generation The rotor windings load current of machine is the 70%~100% of rated current.
Step 3：When double-fed asynchronous generator works normally, the vibration signal of continuous acquisition No. eight vibrating sensor and turn Each five groups of electron current value, is filtered noise reduction, then time-frequency conversion is obtained by data analysis module to the vibration signal collected To the component amplitude of five each frequency spectrums of Zu Ge roads vibration sensor signal.
Step 4：Vibration signals spectrograph is sampled to each road vibrating sensor each group respectively in 937.5Hz~1562.5Hz frequency ranges The amplitude of interior vibration signal whole component is summed, and vibrating sensor five groups of summing values in Zai Duige roads carry out average value meter Calculate, then average value is converted into, obtain each road vibrating sensor scaled value, each road vibrating sensor scaled value is multiplied by respectively Certain coefficient, obtains placing the temperature reference threshold value T of each road vibrating sensor position in double-fed asynchronous generator1i, i is vibration biography The quantity of sensor；Mean value calculation is carried out to five group rotor current values, obtains rotor current reference value I；And in host computer PC Data analysis module memory storage temperature reference threshold value T1iWith rotor current reference value I.
Step 5：Load condition detection, three groups of continuous sampling are carried out to the double-fed asynchronous generator of a unknown failure situation The vibration signal and rotor current of somewhere vibrating sensor, calculate 937.5Hz~1562.5Hz frequency ranges of vibration signal at this The sum of interior each component amplitude, is converted into after asking three class values average, then scaled value is multiplied by certain coefficient, and it is real to try to achieve temperature at this Survey threshold value T2i, i is the quantity of vibrating sensor；Mean value calculation is carried out to three group rotor current values, obtains rotor current actual measurement Value I*；By temperature actual measurement threshold value T at this2iWith temperature reference threshold value T at this1iIt is divided by, obtains temperature threshold ratio value λi, i is to shake The quantity of dynamic sensor, and judge hot-spot failure whether occurs at this.
Preferably, the time-frequency conversion after vibration signal filtering noise reduction uses Fourier transformation.
The sum of the spectrum component amplitude of vibration signal at 937.5Hz~1562.5Hz frequency ranges is converted into using following formula：
Wherein, AxWhen being rotor loading situation, under any rotor current at vibration signal 937.5Hz~1562.5Hz frequency ranges The sum of each component amplitude；A937.5~1562.5It is AxScaled value；K is the ratio of rotor current reference value I and rotor current measured value I* Value.
Preferably, the certain coefficient multiplied is 2.2~3；Wherein can be more preferably 2.6.As preferred side Case, judges hot-spot failure whether occurs at this, includes the following steps：
Work as λiDuring more than 2, then occurs obvious hot-spot failure at this；
Work as λiWhen between 1 and 2, then occurs slight hot-spot failure at this；
Work as λiDuring less than or equal to 1, then hot-spot failure does not occur at this.
As shown in Figure 1, double-fed asynchronous generator hot-spot fault diagnosis system, includes eight vibrating sensors and one Current transformer is connected in parallel on translation interface input terminal respectively, translation interface output terminal and data collecting instrument, data analysis module according to Secondary connection；The translation interface is used to vibration signal being converted into current signal.The current transformer is arranged on double-fed asynchronous At the rotor windings of generator, data collecting instrument, which gathers the vibration signal that each vibrating sensor detects and is sent to, is provided with number According to the host computer PC of analysis module, this vibration signal is stored host computer PC and calculating processing, and carries out breakdown judge.
As shown in Fig. 2, stain represents vibrating sensor in figure, eight vibrating sensors rely on the powerful absorption of magnet base Power is inhaled as follows in electric brush slip ring surface, specific distributing position：Six of which sensor be individually positioned at slip ring surface brush with The contact position of slip ring；Two other is individually positioned in brush support frame surface and slip ring and brush connectivity port.No. 1 survey in figure The vibrating sensor of point is absolute fix inside double-fed asynchronous generator.
As shown in Figure 3, Figure 4, it is respectively shaking when hot-spot failure does not occur and hot-spot failure occurs for No. 1 measuring point Dynamic signal power spectrogram.Comparison diagram 3 and Fig. 4 can be seen that No. 1 measuring point of contact position of brush and slip ring occurs at slip ring surface During hot-spot failure, the signal of 937.5Hz~1562.5Hz frequency ranges can substantially increase in vibration signal, can sentence as criterion Whether No. 1 point position slip ring surface that breaks occurs hot-spot failure.
The above is only the preferred embodiment of the present invention, it should be pointed out that：For the ordinary skill people of the art For member, various improvements and modifications may be made without departing from the principle of the present invention, these improvements and modifications also should It is considered as protection scope of the present invention.

Claims (7)

  1. A kind of 1. double-fed asynchronous generator hot-spot method for diagnosing faults, it is characterised in that：Comprise the following steps：
    Step 1：Double-fed asynchronous generator hot-spot fault diagnosis system is built, the system comprises：Translation interface is used for will Vibration signal is converted into current signal, data collecting instrument, data analysis module, multiple vibrating sensors and a Current Mutual Inductance Device；The vibrating sensor is arranged on inside double-fed asynchronous generator, and the current transformer is arranged on double-fed asynchronous generator Rotor windings at；
    Step 2：It is 10kHz to set data collecting instrument sample frequency, and sampling number is 4000, sets double-fed asynchronous generator Rotor windings load current is the 70%~100% of rated current；
    Step 3：When double-fed asynchronous generator works normally, vibration signal and the rotor electricity of continuous acquisition multichannel vibrating sensor Flow valuve is each multigroup, is filtered noise reduction to the vibration signal collected by data analysis module, then time-frequency conversion obtains more The component amplitude of each frequency spectrum of Zu Ge roads vibration sensor signal；
    Step 4：Vibration signals spectrograph is sampled to each road vibrating sensor each group respectively in 937.5Hz~1562.5Hz frequency ranges The amplitude of vibration signal whole component is summed, and vibrating sensor multigroup summing value in Zai Duige roads carries out mean value calculation, then Average value is converted into, obtains each road vibrating sensor scaled value, each road vibrating sensor scaled value is multiplied by necessarily respectively Coefficient, obtains placing the temperature reference threshold value T of each road vibrating sensor position in double-fed asynchronous generator1i, i is vibrating sensor Quantity；Mean value calculation is carried out to multigroup rotor current, obtains rotor current reference value I；And in the data of host computer PC Analysis module memory storage temperature reference threshold value T1iWith rotor current reference value I；
    Step 5：Load condition detection, the multigroup somewhere of continuous sampling are carried out to the double-fed asynchronous generator of a unknown failure situation The vibration signal and rotor current of vibrating sensor, calculate each in 937.5Hz~1562.5Hz frequency ranges of vibration signal at this The sum of component amplitude, is converted into after asking more class values average, then scaled value is multiplied by certain coefficient, is tried to achieve temperature at this and is surveyed threshold Value T2i, i is the quantity of vibrating sensor；Mean value calculation is carried out to multigroup rotor current, obtains rotor current measured value I*； By temperature actual measurement threshold value T at this2iWith temperature reference threshold value T at this1iIt is divided by, obtains temperature threshold ratio value λi, i is vibrating sensing The quantity of device, and judge hot-spot failure whether occurs at this.
  2. A kind of 2. double-fed asynchronous generator hot-spot method for diagnosing faults according to claim 1, it is characterised in that：Institute State multiple vibrating sensors and be placed on the contact position of brush and slip ring at slip ring surface, or be placed on brush support frame surface With slip ring and brush connectivity port position.
  3. A kind of 3. double-fed asynchronous generator hot-spot method for diagnosing faults according to claim 1, it is characterised in that：Institute State the time-frequency conversion after vibration signal filtering noise reduction and use Fourier transformation.
  4. A kind of 4. double-fed asynchronous generator hot-spot method for diagnosing faults according to claim 1, it is characterised in that：Adopt The sum of the spectrum component amplitude of vibration signal at 937.5Hz~1562.5Hz frequency ranges is converted into following formula：
    <mrow> <msub> <mi>A</mi> <mrow> <mn>937.5</mn> <mo>~</mo> <mn>1562.5</mn> </mrow> </msub> <mo>=</mo> <mfrac> <mn>1</mn> <msup> <mi>K</mi> <mn>2</mn> </msup> </mfrac> <msub> <mi>A</mi> <mi>x</mi> </msub> </mrow>
    Wherein, AxWhen being rotor loading situation, under any rotor current each point at vibration signal 937.5Hz~1562.5Hz frequency ranges Measure the sum of amplitude；A937.5~1562.5It is AxScaled value；K is the ratio of rotor current reference value I and rotor current measured value I*.
  5. A kind of 5. double-fed asynchronous generator hot-spot method for diagnosing faults according to claim 1, it is characterised in that：Institute State certain coefficient and be arranged to 2.2~3.
  6. A kind of 6. double-fed asynchronous generator hot-spot method for diagnosing faults according to claim 5, it is characterised in that：Institute State certain coefficient and be arranged to 2.6.
  7. A kind of 7. double-fed asynchronous generator hot-spot method for diagnosing faults according to claim 1, it is characterised in that：Institute State and judge hot-spot failure whether occurs at this, include the following steps：
    Work as λiDuring more than 2, then occurs obvious hot-spot failure at this；
    Work as λiWhen between 1 and 2, then occurs slight hot-spot failure at this；
    Work as λiDuring less than or equal to 1, then hot-spot failure does not occur at this.
CN201711210361.9A 2017-11-27 2017-11-27 A kind of double-fed asynchronous generator hot-spot method for diagnosing faults Pending CN108008296A (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110211607A (en) * 2019-07-04 2019-09-06 山东中医药高等专科学校 A kind of English learning system based on sensing network
CN110687446A (en) * 2019-07-15 2020-01-14 浙江运达风电股份有限公司 Double-fed wind driven generator electric brush and slip ring early fault diagnosis method

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Publication number Priority date Publication date Assignee Title
CN102175440A (en) * 2011-01-24 2011-09-07 华北电力大学 Method for identifying hot bending failure of large-sized generator set in real time
CN105223444A (en) * 2015-10-20 2016-01-06 国家电网公司 The inner local overheating of oil-filled transformer judges and heat spot localization method

Non-Patent Citations (2)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110211607A (en) * 2019-07-04 2019-09-06 山东中医药高等专科学校 A kind of English learning system based on sensing network
CN110687446A (en) * 2019-07-15 2020-01-14 浙江运达风电股份有限公司 Double-fed wind driven generator electric brush and slip ring early fault diagnosis method
CN110687446B (en) * 2019-07-15 2022-02-08 浙江运达风电股份有限公司 Double-fed wind driven generator electric brush and slip ring early fault diagnosis method

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Application publication date: 20180508