CN1170983A - Multiple fault detector for multiway electric appliance winding - Google Patents
Multiple fault detector for multiway electric appliance winding Download PDFInfo
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- CN1170983A CN1170983A CN 97107550 CN97107550A CN1170983A CN 1170983 A CN1170983 A CN 1170983A CN 97107550 CN97107550 CN 97107550 CN 97107550 A CN97107550 A CN 97107550A CN 1170983 A CN1170983 A CN 1170983A
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Abstract
The fault detector has power interface, power circuit and test signal interface and it features that it has vibration circuit, vibration signal output circuit, gate circuit, ADC circuit and computer interface. Together with computer, the detector of the present invention can perform in-situ precision detection and analysis to the inductance and resistance of motor winding and similar electric appliance under protection so as to detect and judge faults in monitored electric appliances. The presen invention makes it possible to realize united, integrated and multifunctional protection of various electric appliances.
Description
The present invention relates to a kind of emergency protective circuit device.
The fault of motor can roughly be divided into two big classes, the one, because the single overcurrent fault that overload causes, the 2nd, non-overload reason class fault, as the inner phase failure of electrical network phase shortage, winding, turn-to-turn short circuit, winding body contact, rotor are swept hall, the rotor winding opens circuit or aluminium groove fault trough etc.Now generally adopt overcurrent protectors such as thermal relay, according to motor operating current size, motor is implemented protection, first kind fault has obtained certain control.For example; No. 92211910.4 disclosed a kind of integrated protector for electric motor of China's utility application; its electronic circuit is adjusted circuit, anti-interference driving automatic reset circuit, actuator and fault-signal indicator elment etc. by external power interface, power circuit, current signal detector, inverse time-lag device, quick-break and is formed; its operation principle promptly is to gather and detect the operating current signal of motor, realizes the protection to motor.But, to the second class fault, promptly non-overload reason class fault, then existing various protectors can not better be protected or can't protect at all.The protector that has promptly enables some of the second class fault (not being whole) protected, and also is that each motor needs a protector, promptly belongs to the separate type protective device, and can not carry out centralized monitor to multiple motors simultaneously.For electrical equipment such as motor are carried out general protection and centralized monitor, be necessary to provide a kind of novel fault monitoring device.
Purpose of the present invention promptly provides and a kind ofly is used by the computer with peripheral hardware, electrical equipment such as motor is carried out the multiple fault detector for multiway electric appliance winding of general protection and centralized monitor.
Multiple fault detector for multiway electric appliance winding of the present invention has external power interface, power circuit and detection signal interface, and is provided with oscillating circuit, gating circuit, oscillatory signal output circuit, analog to digital conversion circuit, computer interface circuit and computer connecting port especially.Wherein, oscillating circuit has the oscillator signal output.Oscillatory signal output circuit has oscillator signal input, oscillator signal output, detection signal output and external power input.Gating circuit has oscillator signal input, oscillator signal output and gating signal input end.Analog to digital conversion circuit has detection signal input and data-signal output.The computer interface circuit has data-signal input, gating control signal output ends and bus end.Power circuit has the external power input.The oscillator signal input of the oscillator signal output termination oscillatory signal output circuit of above-mentioned oscillating circuit, the oscillator signal input of the oscillator signal output selecting circuit passband of oscillatory signal output circuit, the oscillator signal output termination detection signal interface of gating circuit.The gating signal input end of gating circuit connects the gating control signal output ends of computer interface circuit.The same external power interface that connects of power input outside power input and the power circuit outside the oscillatory signal output circuit.The detection signal input of the detection signal output termination analog to digital conversion circuit of oscillatory signal output circuit.The data output end of analog to digital conversion circuit connects the data input pin of computer interface circuit.The bus termination computer connecting port of computer interface circuit.Before using detector of the present invention, the external power interface can be linked to each other with external power source, detection signal interface and desire are detected electrical equipment (as motor) link to each other, and utilize the computer connecting port to link to each other with control bus, address bus and the data wire of peripheral hardware computer.Like this, when this detector is worked, the oscillator signal that is produced by oscillating circuit enters oscillatory signal output circuit through its oscillator signal output, simultaneously, the computer of peripheral hardware as calculated machine connecting port and computer interface circuit to gating circuit input gating control signal, make in the gating circuit a certain detection branch by gating, the electrical equipment that links with this detection branch just becomes the object of current detection.The oscillator signal that enters oscillatory signal output circuit forms the loop through this detection branch, detected electrical equipment winding, external power source and oscillatory signal output circuit.Electric current and this electric current formed voltage in the loop of oscillator signal that flows through this loop is detected, and is converted to the digital quantity of certain form, the computer of machine interface circuit input peripheral as calculated by analog to digital conversion circuit.The digital quantity that the computer of peripheral hardware passes through to be imported calculates the inductance value and the resistance value (or only calculating its inductance value) of protected electrical equipment winding, and analyzes thus and judge whether the electrical equipment winding breaks down, thereby realizes the monitoring to this electrical equipment.In gating circuit of the present invention, can be set up in parallel many detection branch according to actual needs, make each detection branch continuous with different protected electrical equipment respectively.When the computer of peripheral hardware makes each detection branch conducting in the gating circuit successively, can the electrical equipment that link with each detection branch, dropped into operation of power networks be detected, reach the purpose of the multichannel apparatus winding being implemented fault detect.In the present invention, the computer of peripheral hardware can read the data that analog to digital conversion circuit is defeated by by the timing that is provided with of software.Certainly, also can utilize analog to digital conversion circuit to send the request of reading analog-digital conversion data to computer.At this moment, should in analog to digital conversion circuit, set up the request signal output, in the computer interface circuit, set up the request signal input that joins with it simultaneously.In addition, when employed analog to digital conversion circuit had the self-starting analog-digital conversion function, device of the present invention did not need to provide startup analog-to-digital control signal by the computer of peripheral hardware.But if employed analog to digital conversion circuit does not have the self-starting analog-digital conversion function, then needing provides startup analog-to-digital control signal by the computer of peripheral hardware.At this moment, in analog to digital conversion circuit and computer interface circuit, interconnective analog-to-digital conversion signal input end and output should be set respectively.In the present invention, utilize the testing result of gained that external equipment is controlled as need, can also increase executive circuit and peripheral hardware control interface, and corresponding increase is provided with the peripheral hardware control signal output ends in the computer interface circuit, the signal input part of this peripheral hardware control signal output ends and executive circuit is joined, and allow the signal output part of executive circuit and peripheral hardware control interface join.Like this, only need when using this device the outside relay control line of peripheral hardware control interface and protected electrical equipment is linked to each other, the computer of peripheral hardware just can be according to the malfunction of protected electrical equipment, controls or driving sound and light alarm etc. by the concrete protection of executive circuit enforcement.Simultaneously, if the object that detects is an AC Windings formula electrical equipment, also can set up phase discriminator in the present invention, so that in each time detects, determine the initial moment of detection of AC Windings electrical equipment and be engraved in the phase place of three phase mains when stopping, and it is identical to allow initial moment of each detection be engraved in the power supply phase place of living in when stopping, reducing to detect error, and can when breaking down, electrical equipment realize the fault phase of electrical equipment is judged (useful to some polyphase windings electrical equipment).The phase discriminator of being set up should have ac power input end and signal output part, simultaneously also should set up the phase demodulation signal input end at the computer interface circuit, the ac power input end of phase discriminator and external power interface join, and the phase demodulation signal input end of the signal output part of phase discriminator and computer interface circuit links to each other.
The computer of detector of the present invention and peripheral hardware is used; can be successively carry out onlinely accurately detecting and analyzing, all kinds of faults of each monitored electrical equipment are detected judgement the inductance value of each protected motor winding and similar electrical equipment and resistance value (or only to inductance value).Owing to all aforementioned non-overload reason class faults all will cause the variation of motor winding inductance value and resistance value (or only being inductance value), thereby adopt this detector to monitor to the various non-overload reason class fault that all motor took place of its protection.Equally, to other each electric appliances, if when breaking down with the variation of winding inductance value or resistance value, also can adopt this detector to realize fault detect.In addition; because this detector is that all kinds of faults of each electrical equipment are carried out check and analysis one by one and judgement with the being changed to foundation of its inductance value and resistance value (or only with inductance value) uniformly; thereby make utilization modern computer software and hardware technology, the protective device of each electrical equipment and auxiliary on line thereof are made together to be become an integral body of a tightly knit structure, that defencive function is complete and becomes possibility.Be expected to make the protective device of each electric equipment to realize unitized, integrated and versatile, the protective device object of protection that has each electrical equipment now is single, defencive function is single and need to disperse the on-the-spot limitation of installing, debugging respectively thereby break.
Content of the present invention illustrates further with the following Examples, but content of the present invention is not limited only to content related among the embodiment.
Fig. 1 is the circuit block diagram of fault locator among the embodiment 1.
Fig. 2～Fig. 6 is the circuit diagram of embodiment 1.
Fig. 7 is the circuit block diagram of fault locator among the embodiment 2.
Fig. 8 is the circuit diagram of the analog to digital conversion circuit that adopted among the embodiment 2.
Fig. 9 is the circuit block diagram of fault locator among the embodiment 3.
Figure 10 is the circuit diagram of the phase discriminator that adopted among the embodiment 3.
Figure 11 is the circuit diagram of the computer interface circuit that adopted among the embodiment 3.
Figure 12 is the circuit block diagram of fault locator among the embodiment 4.
Figure 13 is the circuit diagram of the executive circuit that adopted among the embodiment 4.
Figure 14 is the circuit diagram of the computer interface circuit that adopted among the embodiment 4.
Embodiment 1:
As shown in Figure 1, multiple fault detector for multiway electric appliance winding in the present embodiment has external power interface 1, power circuit 2 and detection signal interface 3, and is provided with oscillating circuit 4, gating circuit 6, oscillatory signal output circuit 5, analog to digital conversion circuit 7, computer interface circuit 8 and computer connecting port 9 especially.Wherein, oscillating circuit 4 has the oscillator signal output.Oscillatory signal output circuit 5 has oscillator signal input, oscillator signal output, detection signal output and external power input.Gating circuit 6 has oscillator signal input, oscillator signal output and gating signal input end.Analog to digital conversion circuit 7 has detection signal input and data-signal output.Computer interface circuit 8 has data-signal input, gating control signal output ends and bus end.Power circuit 2 has the external power input.The oscillator signal input of the oscillator signal output termination oscillatory signal output circuit 5 of above-mentioned oscillating circuit 4, the oscillator signal input of the oscillator signal output selecting circuit passband 6 of oscillatory signal output circuit 5.The oscillator signal output termination detection signal interface 3 of gating circuit 6.The gating signal input end of gating circuit 6 connects the gating control signal output ends of computer interface circuit 8.The same external power interface 1 that connects of power input outside power input and the power circuit 2 outside the oscillatory signal output circuit 5.The detection signal input of the detection signal output termination analog to digital conversion circuit 7 of oscillatory signal output circuit 5.The data output end of analog to digital conversion circuit 7 connects the data input pin of computer interface circuit 8.The bus termination computer connecting port 9 of computer interface circuit 8.In the present embodiment, analog to digital conversion circuit 7 has additional the request signal output, and computer interface circuit 8 is corresponding to have the request signal input, and the request signal output of above-mentioned analog to digital conversion circuit 7 links to each other with the request signal output of computer interface circuit 8.Herein, the purpose that above-mentioned request signal output and input are set is after analog-to-digital conversion is finished, and is sent the request of readout data signal to the computer of peripheral hardware by analog to digital conversion circuit.But, if, each translation data is regularly read by computer software, then can cancel the request signal output of analog to digital conversion circuit 7 by computer software control, the request signal input of computer interface circuit 8 also can correspondingly be cancelled.
As shown in Figure 2, in the present embodiment, external power interface 1 is contact JXA, JXB, JXC, detection signal interface 3 is contact JX1, JX2, JX3, the oscillating circuit 4 that is adopted is by audio frequency amplifier IC1, crystal oscillator J1, resistance R 001～R005, capacitor C 001～C003 and diode D001～D002 constitutes, oscillatory signal output circuit 5 is by diode D101～D103, resistance R 101, capacitor C 101～G103, discharge tube FD101～FD103 and transformer T1, T2, T3 forms, and gating circuit 6 is by photoisolator G1～G3, power field effect pipe V201～V203, discharge tube FD201～FD203, resistance R 201～R203 and diode D201～D203 constitutes.What deserves to be explained is: the detection branch that links to each other with JX1 among the figure is by G1, V201, D201 and R201; FD201 forms; this kind can be provided with a plurality of by each detection branch of forming of photoisolator G, the equal effect pipe of power V, diode D, resistance R and discharge tube FD according to actual needs; with it the contact of Dui Ying detection signal interface also can be provided with a plurality of so that link to each other with a plurality of protected electrical equipment.3 detection branch have only been drawn in the gating circuit shown in Figure 2.Fig. 3 is the physical circuit figure of the analog to digital conversion circuit 7 that adopted in this example.This analog to digital conversion circuit is by voltage follower IC2, IC4, IC19, voltage comparator ic 18, IC20, sampling holder IC3, IC5, analog to digital converter IC7, analog switch IC6, form with door IC21, a diode D301～D306, crystal oscillator J2, J3, resistance R 301～R317, capacitor C 301～C309 and triode Q301.Fig. 4 is the physical circuit figure of the computer interface circuit 8 that adopted in this example, this computer interface circuit is made of buffer IC12, IC13, latch IC14, IC15, decoder IC10, NAND gate IC8 or door IC9 and inverter ic 11, and computer connecting port 9 is a computer standard interface JP.Fig. 5 is a power circuit 2, and it is made of current transformer T4, diode D401～D412, three terminal regulator CW1～CW4 and capacitor C 401～C408.The external power input of above-mentioned power circuit 2 is the elementary two ends of transformer T4, promptly illustrates A ', B ', and they are that terminals JXA, JXB link to each other with external power interface 1 respectively.The oscillator signal output of oscillating circuit 4 is 4 pin of audio frequency amplifier IC1.The oscillator signal input of oscillatory signal output circuit 5 is capacitor C 101 end that links to each other with 4 pin of audio frequency amplifier IC1.The oscillator signal output of oscillatory signal output circuit 5 is the elementary of transformer T2 and power field effect pipe V201, V202, V203 source electrode connecting place.The external power input of oscillatory signal output circuit 5 is the negative electrode of diode D101, D102, D103, i.e. A ', B ', C ', and they are that terminals JXA, JXB, JXC link to each other with external power interface 1 respectively.Detection signal output CX1, the CX2 of oscillatory signal output circuit 5 promptly detect the non-earth terminal of secondary wire set of transformer T2, T3, they respectively with the detection signal input of analog to digital conversion circuit 7, promptly 3 pin of voltage follower IC2, IC4 link to each other.And the oscillator signal input of gating circuit 6 is the source electrode of each power field effect pipe V201, V202, V203.The oscillator signal output of gating circuit 6 is the anode of diode D201, D202, D203, the gating signal input end of gating circuit 6 is CN1, CN2, CN3, be the negative electrode of each photoisolator G1, G2, G3 input diode, it is that 2,5,6 pin of latch IC14 link to each other with the gating control signal output ends of computer interface circuit 8 respectively.The data output end of analog to digital conversion circuit 7 is 16～27 pin of weighted-voltage D/A converter IC7, C20～CZ1 just, they link to each other with 2,4,6,8,11,13,15,17 pin of buffer IC13 and 2,4,6,8 pin of buffer IC12 in the computer interface circuit 8 respectively successively.The bus end of computer interface circuit 8 comprises data/address bus DX, address bus AX and control bus CX.In the present embodiment, the request signal output that above-mentioned analog to digital conversion circuit 7 is set up is CT5, be 28 pin of analog to digital converter IC7,11 pin that the computer interface circuit 8 corresponding request signal inputs of setting up are inverter ic 11, the request signal output of above-mentioned analog to digital conversion circuit 7 links to each other with the request signal output of computer interface circuit 8.If, each translation data is regularly read by computer software by computer software control, then can cancel the request signal output CT5 of analog to digital conversion circuit 7, the request signal input of computer interface circuit 8 also can correspondingly be cancelled.Certainly, need to adopt analog to digital converter this moment with output latch function, as AD676 etc., and its peripheral circuit of corresponding configuration.
As shown in Figure 5, the power circuit in the present embodiment 2 provides three kinds of power supplys altogether: analog power (symbol be
), the driving power of digital power (symbol be ) and VDMOS tube grid (symbol be
), the driving power ground of VDMOS tube grid (
) link to each other with the source electrode of each VDMOS pipe.Each power supply forms by three terminal regulator voltage stabilizing and filtering.Among Fig. 6 symbol be (
) be the earth ground symbol.Circuit shown in Figure 6 is for being drawn the explanation circuit diagram of detection line method by protected electrical equipment inside.As shown in the drawing, if it is delta connection formula motor such as DJl that desire detects electrical equipment, can be after three diode D70l～D703 carry out the common cathode rectification with mid point OAC, the OAB of its three phase winding, OAC, draw detection line by its cloudy altogether some O1, make it with Fig. 2 in the detection contact JX1 of detection signal interface 3 join, and then with gating circuit 6 in isolate the G1 that clamors and link to each other by diode D201, field effect transistor V201, discharge tube FD201, photoelectricity with the detection branch that resistance R 201 constitutes; Suppose that the electrical equipment that desire detects is star connection, Y connection formula motor such as DJ2, can draw detection line by its triple line group asterism O2, make it with detection signal interface 3 in detection contact JX2 join, and then be communicated with detection branch in the gating circuit.Also can be as to three-phase diagonal angle shape articulated motor D J1, shown in DJ3, with the three phase winding mid point OA of DJ3, OB, OC after three diode D704～D706 carry out common cloudy rectification, draw detection line by the altogether cloudy some O3 of its rectification and link to each other, and then link to each other with detection branch in the gating circuit with detection contact JX3 in the detection signal interface 3.Suppose desire to detect electrical equipment be a single-phase electrical equipment, as electromagnetism iron wire bag, contactor coil, monophase machine etc., XQ only needs its mid point O4 is drawn as detection line as shown in Figure 6, makes it to link to each other with a certain detection branch in the gating circuit to get final product.Certainly, to multimachine electrical equipment, also can be as to single-phase electrical equipment, be used as a plurality of single-phase electrical equipment and draw a plurality of detection lines respectively and link to each other with a plurality of detection branch, when detecting, detect respectively as a plurality of single-phase electrical equipment.Need to prove; the present invention can be provided with a plurality of and last similar detection contact and corresponding with it detection branch; each detection line of being drawn by each protected electrical equipment links to each other with the detection branch of certain gating circuit 6 respectively by detection signal interface 3, so that a plurality of electrical equipment are detected monitoring.In addition, form current circuit be provided with for preventing by VDMOS pipe endoparasitism diode with VDMOS pipe diode in series D, discharge tube FD is for preventing that element in parallel is with it damaged by high pressure.Using before this fault examines then instrument; can detect the electrical equipment of monitoring from desire earlier and draw detection line; and make it with detection signal interface 3 in the detection contact join, utilize computer connecting port 9 to link simultaneously, and external power interface 1 linked to each other with protected electrical equipment place electrical network with the computer of peripheral hardware.As shown in Figure 2, three-phase mains A ', B ', C ' link to each other with the negative electrode of diode D101～D103 respectively carry out common positive rectification after, enter oscillatory signal output circuit.Oscillator signal by the output of audio frequency amplifier IC1 the 4th pin enters oscillatory signal output circuit through capacitor C 101, and promptly transformer T1's is elementary.By the principles of electric and electronic engineering as can be known: when electrical network and electrical equipment operate as normal, with respect to the voltage of the common sun point of diode D101～D103, the voltage of the detection contact that links with the protected electrical equipment that is moving is always positive voltage.When for example being diagram DG1 by rheoscope, when the detection branch that links to each other with DG1 by gating, be that CN1 is when being low level, one direct current electric current is then arranged by breakover element, electrical network, motor windings among elementary, current-limiting resistance R101, the D101～D103 that detect diode D201, power field effect pipe V201, transformer T2 in contact JX1, the detection branch, return and detect contact JX1 and form the loop.Simultaneously, because transformer T1's is secondary in parallel with the current-limiting resistance R101 in the above-mentioned loop through capacitor C 102, then on the direct current in above-mentioned loop, the interchange pulsating current that frequency equals the oscillation signal frequency of oscillating circuit 4 outputs will be loaded with simultaneously, transformer T1 will detect the resultant current of above-mentioned direct current and alternating current, and transformer T2 since capacitor C 101 every straight effect, with detect the pulsation alternating current component of above-mentioned interchange pulsating current formed voltage in the above-mentioned loop of flowing through and during detection branch.Output to 3 pin of voltage follower IC2, IC4 in the analog to digital conversion circuit 7 by detection signal output CX1, the CX2 (transformer T2, T3's is secondary) of oscillatory signal output circuit.Show as Fig. 3, by the detection signal of CX2 input after voltage stabilizing didoe D301, D302 pressure limiting, 3 pin of input voltage follower IC2, the 6 pin output by IC2 through crystal oscillator J2 filtering interfering, obtains the oscillator signal of required frequency, sends into 1 pin of sampling holder IC3.After voltage stabilizing didoe D303, D304 pressure limiting, send into 3 pin of voltage follower IC4 by the detection signal of CX1 input, by the 6 pin output of IC4,, obtain the oscillator signal of required frequency again, send into 1 pin of sampling holder IC5 through crystal oscillator J3 filtering interfering.In this process, the detection signal of crystal oscillator J3 output is the same frequency component frequently that shakes with crystal oscillator J3 of flowing through in the electric current of detected electrical equipment winding, electrical network and gating circuit shown in Figure 2, oscillatory signal output circuit, the detection signal of crystal oscillator J2 output be above-mentioned electric current in detected electrical equipment winding, electrical network and gating circuit shown in Figure 2, oscillatory signal output circuit among D101, D102, the D103 during breakover element, in the formed voltage with the same frequency component of crystal oscillator J2.Crystal oscillator J3 output signal compares with earth potential in IC18.When the J3 output signal by negative when becoming positive zero passage, IC18 export high level, makes IC3 to maintenances of sampling of J2 output signal, the while IC19, IC20 resistance R 307～R309, capacitor C 303 composition peak detection circuits.When the output signal of J3 was positive peak, IC20 was output as high level, made IC5 to the maintenance of sampling of the output signal of J3.When IC18, IC20 all export high level, with door IC21 output high level, make simulation switch closure in the IC6, IC5 sampling retention value is admitted to the reference voltage input of analog to digital converter IC7.Simultaneously, during IC21 output high level, form a decline by resistance R 317, R316, capacitor C 309, triode Q301 and dash along the pulse, start IC7 and begin analog-to-digital conversion, the sampling retention value of IC3 is directly sent into the input end of analog signal of IC7.Transformation result is 2,4,6,8 pin of 2,4,6,8,11,13,15,17 and the IC12 of IC13 in C20～C215 input computer interface circuit by 16～27 pin of JC7.After each analog-to-digital conversion finished, analog to digital converter IC7 was that CT5 outwards establishes computer the analog-to-digital conversion control signal that finishes is provided by its 28 pin.The computer of peripheral hardware reads transformation result by the computer interface circuit under this signal effect.By the principles of electric and electronic engineering as can be known, when being output as benchmark with IC5 analog-to-digital conversion is carried out in the output of IC3, the digital quantity of gained is the equivalent reactance value of breakover element among detected electrical equipment winding, electrical network, gating circuit and D101, D102, the D103.In the influence of the equivalent inductance value of ignoring silicon cell, and think that detection signal shakes when frequently constant, the gained digital quantity is detected electrical equipment winding inductance value.In view of the above, we just can adopt aforesaid analytical method, and electrical equipment is carried out fault detect.
In the present embodiment, the computer interface circuit is to link with IBM-PC/AT bus and I/O passage and to design.During work, NAND gate IC8 or door IC9, decoder IC10 decipher and produce the control signal of Y0 to Y7 to address signal under the control of control signal IOW, IOR and AEN.Wherein, Y0 is the output permission control signal of buffer IC13.When Y0 was effective, analog-to-digital conversion least-significant byte CZ0～CZ7 was sent to data/address bus DX.Y1 is that the output of buffer IC12 allows control signal.When Y1 was effective, high 4 the CZ8～CZ12 of analog-to-digital conversion were transferred into data/address bus DX.As Y0, when Y1 is invalid, the output of IC12, IC13 is high-impedance state over the ground.Y4 is anti-phase through inverter ic 11 to be Y4, allows control end as the data latching of IC14, by IC14 being latched different data, change to CN1, CN2, CN3 to assignment, to select different detected objects.
In the present embodiment, the data in the detector, address and control bus link to each other with the interface JP that the connection computer interface promptly meets IBM-PC/AT bus and I/O channel standard, link to each other with the expansion slot of the computer of peripheral hardware by JP, can introduce this detector to the computer bus of peripheral hardware.When the computer of peripheral hardware becomes one when whole closely with this detector, this connects computer interface and will be straightway arranged side by side with the line of peripheral hardware computer.
As shown in the above description: the detection signal of crystal oscillator J3 output be flow through detected winding, detect in the electric current of gating circuit, oscillatory signal output circuit and electrical network same frequency component frequently with crystal oscillator J3, the detection signal of crystal oscillator J7 output be above-mentioned electric current at detected electrical equipment winding, the gating circuit of flowing through, form in the voltage same frequency component among diode D101, D102, the D103 when breakover element and electrical network with crystal oscillator J2.Establish outside under the control of computer, in analog to digital converter, two analog quantitys are carried out division arithmetic, digitlization, and with digitized signal input peripheral computer, by above stated specification as can be known, this digital quantity is the equivalent inductance value of detected electrical equipment winding.Because protected electrical equipment winding is taking place that mains supply phase shortage, the inner phase failure of winding, turn-to-turn or phase fault, winding body contact, rotor are swept hall, the rotor winding opens circuit or during fault such as short circuit, aluminium groove fault trough, all will cause this detector to detect to such an extent that the equivalent inductance value of electrical equipment winding changes.Therefore, on the one hand can be at known electric equipment for just often, artificial notice computer detects this electrical equipment, and will detect the equivalent inductance value deposit the register of peripheral hardware computer in as fiducial value, in detection time afterwards, with detect the instantaneous value or the mean value of inductance value compare with fiducial value in the register, and, apparatus failure is detected according to its variable quantity.On the other hand, with regard to detect the equivalent inductance value of electric equipments such as electrical equipment winding with regard to, the variation of the factors such as magnetic saturation that will cause owing to voltage and voltage changes.To a definite electrical equipment, the frequency width of cloth relation and the phase relation of its variation are determined.And when breaking down, as giving the interrupted short circuit of winding instantaneous time surely, opening circuit and the opening circuit of rotor winding, short circuit etc., the correlation etc. that detects frequency width of cloth characteristic that the equivalent inductance value that obtains changes and voltage and inductance value variation will change.Therefore, also can by to detect the equivalent inductance value of electric equipment carry out frequency domain or the width of cloth and comparative analysis etc. frequently mutually, the electrical equipment winding is carried out fault detect.And above analysis both can be the comparison on different time to same winding or electrical equipment, can carry out simultaneously the same time again different windings or different electrical equipment are compared, to reach the accurate judgement to apparatus failure.Also can carry out sound and light alarm, participate in the concrete control of detected electrical equipment according to testing result.Or with foundation and the reference of testing result as maintenance repair.What deserves to be explained is: the Frequency Response of crystal oscillator J2, J3 should be consistent, and its resonance frequency can be the J1 fundamental frequency frequently of shaking, and also can be the J1 a certain harmonic frequency frequently of shaking, and crystal oscillator J1, J2, J3 should have frequency stability preferably.In the present embodiment, if C101 among Fig. 2 link to each other with 4 pin of IC1 hold and (
) indirect one newly-increased resistance, again C101 link to each other with transformer T1 end and diode D101～D103 altogether oedoeagus link to each other, and cancel transformer T1 and capacitor C 102, oscillating circuit do not adopt the analog electrical plateau (symbol be
) and adopt VDMOS pipe driving power (symbol be
, and this moment, this power supply should be ± duplicate supply of 15V), then the oscillatory signal output circuit after this changes is made up of transformer T2, T3, resistance R 101, newly-increased resistance, capacitor C 101, C103, diode D101～D103 and discharge tube FD101～FD103.Oscillatory signal output circuit after this changes still has the identical function before changing.Certainly, this moment transformer T2, T3 secondary winding earthing mode must with simulation ground (
) link to each other.
Embodiment 2:
The detector structure of present embodiment is similar to embodiment 1, and different is, the detector in the present embodiment is changed the circuit structure of analog to digital conversion circuit 7, (promptly can this Fig. 8 directly replaces the Fig. 3 among the embodiment 1) as shown in Figure 8.The circuit block diagram of detector as shown in Figure 7 in the present embodiment.In the present embodiment, analog to digital conversion circuit 7 has additional the analog-to-digital conversion signal input end, computer interface circuit 8 has additional the analog-to-digital conversion control signal output ends, and the analog-to-digital conversion signal input end of analog to digital conversion circuit 7 connects the analog-to-digital conversion control signal output ends of computer interface circuit 8.Fig. 2, Fig. 4, Fig. 5 and Fig. 6 of being provided with embodiment 1 combine with Fig. 8 that this example newly provides, and have promptly constituted the circuit structure diagram of detector in this example.As shown in Figure 8, the modulus that is adopted in this example is walked around and is changed circuit 7 and be made of voltage follower IC2, IC4, sampling holder IC3, IC5, analog switch IC6, analog to digital converter IC7, resistance R 301, R302, R311, R312, R314, R315, capacitor C 301, G302, C304～C308 and diode D301～D304.The analog-to-digital conversion signal input end of above-mentioned analog to digital conversion circuit 7 is CT1 (12 pin of sampling holder IC3, JC5), CT2 (1 pin of analog switch JC6), CT3 (16 pin of analog switch IC6), CT4 (5 pin of analog to digital converter IC7), they link to each other with the analog-to-digital conversion control signal output ends of computer interface circuit 8 respectively.Wherein 2 pin of CT1 and latch IC15 link to each other, and 5 pin of CT2 and IC15 link to each other, and 6 pin of CT3 and IC15 link to each other, and 9 pin of CT4 and IC15 link to each other.
The course of work of present embodiment detector is substantially the same manner as Example 1, just in the analog to digital conversion circuit course of work, by the computer of peripheral hardware as calculated the machine interface circuit to CT1, be sampling holder IC3, the 12 pin input high levels of IC5, make IC3, IC5 is respectively to crystal oscillator J2, the maintenance of sampling of one simulation signal of J3 output, and successively respectively to 1 pin and 16 pin of analog switch IC6, be CT2, the CT3 input high level, by IC6 successively JC3, the input end of analog signal of the sampling retention value input analog-to-digital converter JC7 of JC5, be the 5 pin input low levels of analog to digital converter IC7 then to CT4, start IC7 the analog quantity of being imported is carried out analog-to-digital conversion.After this process is identical with last example, and promptly transformation result is 2,4,6,8 pin of 2,4,6,8,11,13,15,17 and the IC12 of IC13 in C20～C215 input computer interface circuit by 16～27 pin of IC7.Y3 is anti-phase through inverter ic 11 to be Y3, allows control end as the data latching of latch IC15, by IC15 being latched different data, to finish the control to analog to digital conversion circuit 7.The control signal that analog-to-digital conversion finishes is held through inverter ic 11 anti-phase IRQ3 for input control bus behind the CT5 by CT5.The computer of peripheral hardware reads transformation result by the computer interface circuit under this signal effect.Simultaneously, because the change of analog to digital conversion circuit, the detector of present embodiment also can detect the equivalent resistance of this electrical equipment except that can detecting the equivalent inductance value of protected electrical equipment.When this detector is worked, the detection signal of crystal oscillator J3 output be flow through detected winding, detect in the electric current of gating circuit, oscillatory signal output circuit and electrical network same frequency component frequently with crystal oscillator J3, the detection signal of crystal oscillator J2 output be above-mentioned electric current at detected electrical equipment winding, the gating circuit of flowing through, form in the voltage same frequency component among diode D101, D102, the D103 when breakover element and electrical network with crystal oscillator J2.Establish outside under the control of computer, to these two analog quantitys sample, digitlization, and with digitized signal input peripheral computer, just can in the computer of peripheral hardware, carry out digital processings such as functional transformation to this two digital signal, obtain this two digital signal separately about the transfer function of time, and the relation of two transfer functions thus, and then draw the equivalent resistance and the equivalent reactance value of the diode of conducting among detected electrical equipment winding, electrical network, gating circuit and D101, D102, the D103.Because the equivalent inductance of silicon cell can be ignored in the above-mentioned path, when crystal oscillator J1, J2, J3 frequency stability better can think that frequency is constant, detect the equivalent reactance value be the equivalent inductance value of detected electrical equipment winding.Constant or change when little at line voltage mean value, the equivalent resistance of silicon cell is also with constant or change little in the above-mentioned path.According to detect the variable quantity of equivalent resistance, can draw the variable quantity of the equivalent resistance of nonsilicon elements such as detected electrical equipment winding, electrical network.Because protected electrical equipment winding is taking place that mains supply phase shortage, the inner phase failure of winding, turn-to-turn or phase fault, winding body contact, rotor are swept hall, the rotor winding opens circuit or short circuit, aluminium groove fault trough, when increasing or the like fault for the contactor contact resistance of tested electric power supply, all will cause this detector to detect to such an extent that the equivalent inductance value or the equivalent resistance (or equivalent resistance and equivalent inductance value) of electrical equipment winding changes.For example, when the electrical equipment winding is short-circuited, will cause detecting to such an extent that equivalent resistance and equivalent inductance value change.When rotor taking place sweep, will cause detecting to such an extent that the equivalent inductance value changes.Coming in contact resistance for the contactor of tested electric power supply when increasing, will cause detecting equivalent resistance change.Therefore, this detector can be at above-mentioned variation, and equivalent inductance value and the equivalent resistance to the electrical equipment winding that detects gained carries out various analyses simultaneously, and apparatus failure is accurately judged.
Embodiment 3:
The detector structure of present embodiment is similar to embodiment 2, and different is that the detector in the present embodiment has increased phase discriminator as shown in figure 10, and correspondingly computer interface circuit 8 has been carried out change as shown in figure 11.The circuit block diagram of present embodiment as shown in Figure 9, the phase discriminator of being set up 10 has external power input and phase demodulation control signal output ends, simultaneous computer interface circuit 8 has additional the phase demodulation signal input end, the phase demodulation control signal output ends of phase discriminator 10 connects the phase demodulation signal input end of computer interface circuit 8, and power input connects external power interface 1 outside the phase discriminator 10.Combine with Figure 10 and Figure 11 that this example newly provides by Fig. 2, Fig. 5, Fig. 6 and Fig. 8 that above embodiment provided, promptly constituted the circuit structure diagram of detector in this example.As shown in figure 10, the phase discriminator of being set up in this example is made up of photoisolator G501～G506, diode D501～D512 and resistance R 501～R507.Wherein, the input diode of diode D501～D512 and photoisolator G501～G506 is formed three-phase full wave rectifier circuit jointly, and R507 is this circuit load.The input diode anode of G501～G503 is that the negative electrode of G504～G506 input diode is the external power input of phase discriminator, and it links to each other with external power interface A ', B ', C ' three phase mains respectively.G501～G506 output triode is launched the very phase discrimination signal output of phase discriminator 10, output phase discrimination signal CH1～CH6.Computer interface circuit shown in Figure 11 is compared with computer interface circuit shown in Figure 4 among the above embodiment in this example, only established a buffer IC16 more, 2,4,6,8,11,13 pin of buffer IC16 are the phase discrimination signal input of computer interface circuit, and they link to each other with the output triode emitter of the G501～G506 of phase discriminator 10 respectively.When Y2 was low level, the output of IC16 allowed end effectively, and the peripheral hardware computer reads phase discrimination signal CH1～CH6 by IC16 in the computer interface circuit.
In conjunction with oscillatory signal output circuit shown in Figure 2, shown in Figure 6ly draw detection line circuit and above-mentioned phase discriminator shown in Figure 10 by protected electrical equipment; as can be known: to polyphase windings electrical equipment; its each phase winding mid point drawn and by diode rectification when drawing the protection detection line; as shown in Figure 6 DG1, detection line 01 voltage will be identical with the mid-point voltage soprano in each phase winding; and the interior common oedoeagus voltage of positive diode D101～D103 altogether of oscillatory signal output circuit shown in Figure 2, will be identical with the minimum phase voltage of voltage in the three phase mains of being imported.For example, when the A phase voltage is minimum, when promptly phase discrimination signal CH6 was high level in the phase discriminator, the common oedoeagus voltage of diode D101～D103 was the A phase voltage, and the common cloudy terminal voltage of diode D701～D703 then is a BC phase winding mid point OBC voltage.The consideration external power source is a constant pressure source, and the inductance that detected this moment is the inductance of BC phase winding.Therefore, according to the phase discrimination signal of phase discriminator output, we can determine that just the winding that is detected is that phase winding, and record in addition.When analyzing, can be to be impedance phase comparison just often in motor windings with this phase winding, can also be with same electrical equipment in other phase winding carry out comparison of variable quantity separately or the like.When breaking down, can also determine that fault occurs in that utmost point winding with this.Simultaneously, the phase discrimination signal that utilizes phase discriminator output is as the initial sum termination control signal that the electrical equipment winding is detected, can reduce the multiple detection error that causes because of factors of voltage, change with factors vary such as voltages because of the magnetic saturation degree and each time detects and be engraved in the power supply the different errors that cause of phase place etc. when initial sum stops as electrical equipment winding inductance value.And this error needs prolongation that the time that the electrical equipment winding detects is eliminated when not having phase discriminator.When single-phase electrical equipment winding is detected with the heterogeneous electrical equipment of directly electrical equipment winding asterism being drawn, though no longer need determine that to institute's detected phase also available phase discriminator is to reduce above-mentioned detection error.
Embodiment 4:
The detector structure of present embodiment is similar to embodiment 2, and different is that the detector in the present embodiment has increased executive circuit and peripheral hardware control interface as shown in figure 13, and correspondingly computer interface circuit 8 has been carried out change as shown in figure 14.The circuit block diagram of present embodiment as shown in figure 12, the executive circuit of being set up 11 has signal input part and signal output part, computer interface circuit 8 has additional the peripheral hardware control signal output ends, the signal input part of executive circuit 11 connects outside the computer interface circuit 8 and establishes control signal output ends, and the signal output part of executive circuit 11 connects peripheral hardware control interface 12.Combine with Figure 13 and Figure 14 that this example newly provides by Fig. 2, Fig. 5, Fig. 6 and Fig. 8 that above embodiment provided, promptly constituted the circuit structure diagram of detector in this example.As shown in figure 13, executive circuit 11 is made up of photoisolator G601～G605, resistance R 601～R605 and capacitor C 601～C605, and JK11～JK52 is peripheral hardware control interface 12.The anode of the input diode of photoisolator G601～G605 is the input CM1～CM5 of executive circuit, and the output of each photoisolator links to each other with separately peripheral hardware control interface respectively, and participates in the relay control of peripheral hardware by the peripheral hardware control interface.Computer interface circuit shown in Figure 14 is compared with computer interface circuit shown in Figure 4, has increased latch IC17.When the Y5 of 6 pin of inverter ic 15 output was high level, IC17 latched the data-signal on the data bus.The data output end of IC17, promptly 17 of IC17,9,6,5,7 pin are the peripheral hardware control signal output ends CM1～CM5 of computer interface circuit, they link to each other with the anode (being the signal input part of executive circuit 11) of the input diode of G601～G605 respectively.By executive circuit and peripheral hardware control interface, the computer of peripheral hardware just can carry out concrete relay control or drive sound and light alarm each protected electrical equipment according to the judgement to each apparatus failure.
What deserves to be explained is that more than just with four embodiment this detector is described, in physical circuit, its circuit also can have multiple variation.Along with carrying out multi-form connection with computer, whole closely as this detector and computer being constituted one, or with both as independently whole, or connect with different computer, and adopt different analog to digital converter or the like, all will make analog to digital conversion circuit, computer interface circuit, connection computer interface and even power circuit etc. change, and just do not describe in detail one by one at this.
Be pointed out that also above embodiment describes with the fault detect to ac electric apparatus.When native system is used for DC power system; can any one links to each other with among power ground and the diode D101～D103; or cancellation D101～D103 and FD101～FD103; power supply ground is linked to each other with the elementary of transformer T1 with R101; simultaneously; the mid point of dc electric apparatus winding drawn with terminals JX1, the JX2 of each detection branch, JX3 etc. link, then this electrical equipment just is included into the protection range of this detector.
In addition; because when protected electrical equipment does not put into operation, the detection resistance value of coupled detection branch will be infinity to some electrical equipment (as three phase electric machine etc.), to some electrical equipment such as relay; contactors etc. will be infinitely great or half of resistance value when be its normal release.Simultaneously, to some heterogeneous electrical equipment, the phase of why when detecting, also can determining to break down mutually.In addition, the public power supply when some electrical equipment partly is when partly electrical network breaks down, by the comparison to each apparatus failure, can find the fault coverage, and further find the fault point.Therefore, concerning a system that constitutes by many electrical equipment, after its each electrical equipment is included in the detection range of this detector, not only can detect, also can realize that the fault self-checking of entire system is surveyed according to the work-based logic relation of each electrical equipment to its single apparatus failure.Simultaneously,, just need concrete outcome of clear and definite its each control because automatic control process will be realized the accurate control to each electrical equipment, and this detector a kind of feedback method as a result of controlling more accurately of also can yet be regarded as.And the above these centralized monitor measure all is vital for realizing factory automation.
As shown in the above description: detector of the present invention is a kind of detector that multichannel apparatus is carried out various fault detects; its principle is: import an oscillator signal successively to detected electrical equipment; and oscillator signal electric current and formed voltage thereof that the input oscillator signal is flow through during by detected electrical equipment, electrical network etc. detect; computer by peripheral hardware is used, successively to each protected electrical equipment and for the equivalent inductance value and the equivalent resistance (or only to equivalent inductance value) of its power supply grid etc. carries out comprehensively, centralized monitor.This detector has been realized carrying out analog-to-digital conversion to the detection signal collection with to detection signal particularly, and realizes functions such as computer and connecting of each electrical equipment.And connecting of this computer and protected electrical equipment is still blank on technical combinations at present.
Claims (5)
1, a kind of multiple fault detector for multiway electric appliance winding, has the external power interface, power circuit and detection signal interface, it is characterized in that being provided with oscillating circuit, oscillatory signal output circuit, gating circuit, analog to digital conversion circuit, computer interface circuit and computer connecting port, oscillating circuit has the oscillator signal output, oscillatory signal output circuit has the oscillator signal input, the oscillator signal output, detection signal output and external power input, gating circuit has the oscillator signal input, oscillator signal output and gating signal input end, analog to digital conversion circuit has detection signal input and data-signal output, the computer interface circuit has the data-signal input, gating control signal output ends and bus end, power circuit has the external power input, the oscillator signal input of the oscillator signal output termination oscillatory signal output circuit of described oscillating circuit, the oscillator signal input of the oscillator signal output selecting circuit passband of oscillatory signal output circuit, the oscillator signal output termination detection signal interface of gating circuit, the gating signal input end of gating circuit connects the gating control signal output ends of computer interface circuit, the same external power interface that connects of power input outside power input and the power circuit outside the oscillatory signal output circuit, the detection signal input of the detection signal output termination analog to digital conversion circuit of oscillatory signal output circuit, the data output end of analog to digital conversion circuit connects the data input pin of computer interface circuit, the bus termination computer connecting port of computer interface circuit.
2, as the described detector of claim I, it is characterized in that analog-digital conversion circuit as described has the request signal output, described computer interface circuit has the request signal input, the request signal input of the request signal output termination computer interface circuit of analog to digital conversion circuit.
3, detector as claimed in claim 1, it is characterized in that analog-digital conversion circuit as described has the analog-to-digital conversion signal input end, described computer interface circuit has the analog-to-digital conversion control signal output ends, and the analog-to-digital conversion signal input end of analog to digital conversion circuit connects the analog-to-digital conversion control signal output ends of computer interface circuit.
4, as claim 1 or 2 or 3 described detectors, it is characterized in that being provided with phase discriminator, described phase discriminator has external power input and phase demodulation control signal output ends, described computer interface circuit is provided with the phase demodulation signal input end, the phase demodulation control signal output ends of phase discriminator connects the phase demodulation signal input end of computer interface circuit, and power input connects the external power interface outside the phase discriminator.
5, as claim 1 or 2 or 3 described detectors, it is characterized in that being provided with executive circuit and peripheral hardware control interface, described executive circuit has signal input part and signal output part, described computer interface circuit is provided with the peripheral hardware control signal output ends, the signal input part of executive circuit connects outside the computer interface circuit and establishes control signal output ends, and the signal output part of executive circuit connects the peripheral hardware control interface.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN97107550A CN1062384C (en) | 1997-02-03 | 1997-06-16 | Multiple fault detector for multiway electric appliance winding |
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN97107351 | 1997-02-03 | ||
| CN97107351.1 | 1997-02-03 | ||
| CN97107550A CN1062384C (en) | 1997-02-03 | 1997-06-16 | Multiple fault detector for multiway electric appliance winding |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1170983A true CN1170983A (en) | 1998-01-21 |
| CN1062384C CN1062384C (en) | 2001-02-21 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN97107550A Expired - Fee Related CN1062384C (en) | 1997-02-03 | 1997-06-16 | Multiple fault detector for multiway electric appliance winding |
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| CN (1) | CN1062384C (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104035435A (en) * | 2014-06-17 | 2014-09-10 | 上海华兴数字科技有限公司 | Drive port self-diagnostic circuit |
| CN108732522A (en) * | 2017-04-21 | 2018-11-02 | 南京南瑞继保电气有限公司 | The test device and method of generator rotor interturn short-circuit fault monitoring device |
-
1997
- 1997-06-16 CN CN97107550A patent/CN1062384C/en not_active Expired - Fee Related
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104035435A (en) * | 2014-06-17 | 2014-09-10 | 上海华兴数字科技有限公司 | Drive port self-diagnostic circuit |
| CN104035435B (en) * | 2014-06-17 | 2016-08-24 | 上海华兴数字科技有限公司 | A kind of driving port self-diagnostic circuit |
| CN108732522A (en) * | 2017-04-21 | 2018-11-02 | 南京南瑞继保电气有限公司 | The test device and method of generator rotor interturn short-circuit fault monitoring device |
| CN108732522B (en) * | 2017-04-21 | 2020-07-28 | 南京南瑞继保电气有限公司 | Testing device and method for generator rotor winding turn-to-turn short circuit fault monitoring device |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1062384C (en) | 2001-02-21 |
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