CN2255690Y - Electric motor protector - Google Patents
Electric motor protector Download PDFInfo
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- CN2255690Y CN2255690Y CN 96231053 CN96231053U CN2255690Y CN 2255690 Y CN2255690 Y CN 2255690Y CN 96231053 CN96231053 CN 96231053 CN 96231053 U CN96231053 U CN 96231053U CN 2255690 Y CN2255690 Y CN 2255690Y
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- motor
- circuit
- current
- sensing circuit
- signal sensing
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Abstract
The utility model discloses a motor protector. The utility model can adopt different devices, such as a transformer, a current mutual inductor, a contactor attraction coil, a capacitor, etc. as power supplying equipment for an operational power supply. Under different conditions, the utility model has multiple functions of rejecting switching on or automatic trip and cutting off a circuit of the motor when faults, such as overcurrent, temperature, insulation, overvoltage, undervoltage, phase failure, short circuit, etc. happen. On the condition of reliable performance, the circuit structure of the utility model is as simple as possible, the utility model integrates the advantages of the prior art and forms a more advanced system, and the utility model is suitable for different requirements under different conditions with treatment in accordance with local conditions. The applicability of the utility model is wide and the utility model is an actually applied new technology of motor protection with potential.
Description
The utility model---a kind of motor protecter belongs to electrotechniical control protector.
In the prior motor resist technology, large-size machine adopts the expensive privacy protection equipment that is worth; The middle and small motor great majority that consumption is huge still adopt thermal relay, fuse as protection equipment, perhaps without any protection.And thermal relay, fuse all be difficult to adjust more exactly, and operate time is long, can not protect motor well.In recent years some of Chu Xianing new in, small machine protector or function singleness, work is reliable inadequately, perhaps the cost of manufacture height is difficult to promote the use of.Though what have also can play the certain protection effect, fail to suit measures to local conditions to satisfy the motor of working under the different situations multiple different demands to protection; Have because of the design on defective, can not solve some particular challenge in the electric motor protecting.
The purpose of this utility model is to guarantee reliable in function, under the total thinking of this motor protecter optimal design of the structure that strives for simplification, motor in the face of domestic operation, often condition of work is abominable for particularly medium and small motor, overload work, imperfect maintenance, spoilage is big, be difficult to find the present situation that is fit to the motor protecter that self uses, a kind of simple, inexpensive, motor protecter that complete function is reliable, easy to install is provided; Its different embodiment different situations of can suiting measures to local conditions to be applicable to, thereby improve its utilization rate to greatest extent, reduce the device damage and the fire incident that cause because of electrical fault.
The main feature of the utility model circuit structure, design is as follows:
It is by operating power, signal sensing circuit, the control amplifying circuit, relay is formed, it is one of following 4 kinds that the operating power that it is characterized in that it can be: or use transformer-supplied, at this moment its signal sensing circuit comprises the current signal sensing circuit at least, temperature signal sensing circuit, the insulation signal sensing circuit that is linked to be by the divider resistance of the auxiliary normally closed contact of Insulation Test power supply, motor main switch, motor housing, 1 end of incoming cables of motor, current-limiting resistance, output signal; Or 2 side power supplies of Current Transformer, at this moment its signal sensing circuit comprises the current signal sensing circuit at least; Or with the pull-in winding power supply of the contactor of motor, at this moment its signal sensing circuit comprises the temperature signal sensing circuit at least; Or with powering behind the capacitance decompression, at this moment its signal sensing circuit comprises current signal sensing circuit or temperature signal sensing circuit at least; The dc output end of its operating power and control, amplifying circuit with just, the zero potential end links to each other; Its each signal sensing circuit is exported 2 utmost point pipes by signal separately respectively and is linked to each other with control, input amplifier; The pull-in winding of relay links to each other with control, amplifying circuit and output, and the contact of relay is connected among the loop of control motor main switch break-make.
Operating power with transformer-supplied is made up of transformer and rectification circuit; The operating power of 2 sides of Current Transformer power supply is by 2 sides of current transformer and rectification circuit, and the current signal resistance that 2 utmost point pipe series combination or voltage-stabiliser tube, series connection are with it shunted in the voltage stabilizing that is parallel to rectification circuit output end is formed; Operating power with the pull-in winding power supply of the contactor of motor is in series by contactor pull-in winding and rectification circuit, and rectification circuit input end also is in parallel with the contactor normally closed contact.
The current signal sensing circuit is obtained signal by 1 grade or 2 grades of current transformers; The temperature signal sensing circuit is made up of humid test power supply, thermistor or other temperature-sensitive elements; Temperature-sensitive element can be loaded on motor coil, motor housing, motor bearings vicinity; Each current signal, temperature signal sensing circuit have Signal Regulation potentiometer separately respectively.
The Insulation Test power supply both can be obtained by direct current operative power source; Can obtain through electric capacity, resistance step-down current limliting by AC power again; Also can be got by 2 sub-high pressure side-draws of Insulation Test transformer, 1 side of this transformer links to each other with 2 sides of operating power transformer; The humid test power supply by direct current operative power source through the resistance step-down; Obtain after the voltage-stabiliser tube voltage stabilizing.
Control, amplifying circuit comprise the two-stage amplifying circuit at least, and the input amplifier element of elementary amplifying circuit can be 3 utmost point pipe or voltage comparators, and the amplifier element of final stage power amplification circuit is 3 utmost point pipes.
The contact of relay is connected among the loop of control motor main switch break-make, both can be in the pull-in winding loop of 1 docking point of the relay contactor that is connected in series with motor, 1 docking point that can be relay again is connected in series with in the no-voltage trip coil or closing coil loop of starting switchs such as automatic air-break switch or auto-transformer starter, 1 docking point that can also be relay is connected in the shunt opening trip coil or breaking coil loop of automatic air-break switch, also can be that 1 docking point of relay is connected in series with in the breaking coil loop that drives the disconnecting link switch.
Be connected in series with by relay 1 docking point among the loop of pull-in winding of contactor of motor, this contactor both can be directly with the alternating current adhesive; Again can the direct current adhesive, when with the direct current adhesive, can add the DC operation circuit of forming by this contactor normally closed contact, 2 utmost point pipes, electric capacity or electric capacity and transformer.
Embodiment of the present utility model and as follows corresponding to the description of drawings of each embodiment: the mark among the figure is as repeatedly appearance in different figure, and the implication of being given when its implication all occurs for the first time with it is identical, explanation no longer separately
Fig. 1 is the 1st kind of embodiment.Its operating power is powered by transformer T, its signal sensing circuit comprises current signal, temperature signal, bearing temperature signal, insulation signal, overvoltage signal, brownout signal, phase failure no-load signal, short-circuit signal, overtime frequent self-starting signal sensing circuit, and its signal is exported 2 utmost point pipes and is respectively D
L, D
M, D
B, D
0, D
8, D
9, D
d, D
K, D
P, its Insulation Test power supply, humid test power supply are by direct current operative power source anode E
+Through resistance R
2Step-down, voltage-stabiliser tube D
W2Obtain E after the voltage stabilizing
+ 2Be its anode, with direct current operative power source negative terminal E
0For its negative terminal (also can be directly with E
+Be the Insulation Test power positive end).
The implication of all the other marks is as follows among Fig. 1: R
1, R
2, R
3, R
4, R
5, R
6, R
7, R
70, R
Z, R
F, R
01, R
02, R
22, R
32, R
52Be resistance; C
LBe electric capacity; C
0, C
1, C
2, C
20, C
3, C
4, C
5, C
12, C
42, C
FBe electrochemical capacitor; D
1* 4 and D
2* 4 are the bridge rectifier that 42 utmost point pipes are formed, D
3, D
4, D
5, D
6, D
7, D
20, D
32, D
42, D
52, D
62, D
72Be 2 utmost point pipes; R
W1, R
W2, R
W3, R
WB, R
W4, R
WK, R
Wt, R
Wt2Be potentiometer, wherein R
WK, R
Wt2Be the internal regulation potentiometer; D
W0, D
W1, D
W2Be voltage stabilizing 2 utmost point pipes; FG
R, FG
G, FG
YBe luminous 2 utmost point pipes; F is a buzzer; J, J
2Be respectively the pull-in winding of first relay and the 2nd relay, J
2KBe J
2Normal opened contact; CJ
K1, CJ
K2For often opening auxiliary contact, CJ as the A.C. contactor of motor switch
b, CJ
B1, CJ
B2, CJ
B3The normally closed auxiliary contact of A.C. contactor for this reason; K
2Be the operating power switch; RD is a fuse; 1 side two ends of transformer are T
1a, T
1b, 2 side two ends are T
2a, T
2bLH
1, LH
2Be respectively 1 grade, 2 grades current transformer (LH
11 time side is series at motor B phase inlet wire B
2In, its 2 sides and LH
21 time side links LH
22 sides are to D
2* 4 input; LH
1, LH
2Also can respectively be 2 or 3 and be sub-packed in 2 phase or 3 phases, each LH at this moment
22 sides should be respectively and proportion resistor---R
W1, R
W4Separate moving fixed end, ratio is 1 to exempt from this resistance, connects all-wave or half-wave rectifying circuit input more respectively, again with each rectification output end parallel connection; Also available than large velocity ratio LH
1, and with the potentiometer R that dotted line was connected as figure
LWReplace LH
2And C
L); A
1, B
1Be A phase, B phase mains side, O
3Be motor housing; HA, TA are combined floodgate, trip button, HA
K2Be the 2nd pair of normal opened contact of HA; HA
W, HA
WK2Be respectively the outer switch knob of protector, its 2nd pair of normal opened contact; BG
1, BG
2, BG
12, BG
22Be 3 utmost point pipes; R
MF, R
MBBe thermistor; (F also can change tongue tube into and carry F).
The structure of Fig. 1 embodiment is except that stating part, and all the other structures are as follows: D
1* 4 inlet is 2 sides of T, exports to be E
+, E
0, C
5, D
W1Be parallel to E
+, E
0Between; LH
2With C
L(a plurality of LH in parallel
2Then exempt from C
L), through D
2* 4 rectifications are again with R
W1, R
WKBe connected to E
0, form the current signal sensing circuit, with R
W1The moved end connects R
Wt, D
LTo BG
1Base stage is its signal output apparatus (R
WtBe running current inverse time lag regulator potentiometer), by R
WKThe moved end connects D
KTo BG
12Base stage is short circuit current signal output apparatus (if LH
1, LH
2Do not have 7I
HThen exempt from this circuit), by R
W1The moved end connects R
Wt2, D
PTo BG
12Base stage is overtime, frequent self-starting signal input circuit; By E
+ 2Connect R
MF, R
W3Form the temperature signal sensing circuit, by R
W3The moved end is from D
MTo BG
1Base stage is exported this signal; By E
+ 2Connect CJ
B1, B
2By generator stator winding insulation to O
3Connect CJ
B3(O
3, B
2Also can exchange the order of connection, with O
3But the CJ normally closed contact position that connects is short circuit also), R
01, R
02, D
0Form the insulation signal sensing circuit, by D
0To BG
1Base stage is exported its signal; By R
7Connect R
70, R
W4Form the voltage signal sensing circuit, overvoltage signal is by R
7, R
70Connect point and pass through D
8To BG
1Base stage output, brownout signal is by R
W4The moved end is through CJ
B2, D
9To BG
2Base stage output; By the RW1 moved end through CJ
K2, D
dTo BG
2Base stage is formed phase failure signal sensing circuit, and its signal passes through D
dTo BG
2Output.E
+Connect FG
R, R
1, R
2, BG
1Collector electrode, R
3, R
4, R
20, BG
2Base stage is passed through BG more respectively
1, BG
2Emitter is to E
0, form 2 grades of amplifying circuits; By BG
2Collector electrode connects J, by HA, the HA that is in parallel
W, J
2KWith E
+Link to each other, be the output circuit of this amplifying circuit; By J, HA, J
2KPoint in parallel connects R
22, BG
12Collector electrode, R
22, BG
22Base stage.Pass through BG more respectively
12, BH
22Emitter is to E
0, form 2 grades of amplifying circuits of the 2nd cover; By BG
22Collector electrode connects J
2, by mutually and the HA, the J that connect
2KWith E
+Linking to each other, is the output circuit of the 2nd cover amplifying circuit, and forms J
2In parallel with J positive potential end; R
3, R
4, C
2Form the circuit that operation is prolonged, R
20Connect R
W2, CJ
K1, Xiang Binglian HA
K2With HA
WK2To E
+, again from HA
K2With CJ
K1The point that links to each other connects C
20, the CJ that is in parallel
bWith D
20(CJ
6With D
20But the position is short circuit also) to E
0Form starting delay circuit; Operation delay circuit and starting delay circuit all are in by BG
1, BG
2Deng among the amplifying circuit of forming, BG
2Base input circuit among; In addition, C
1Be connected in D
LGo into end and E
0Between, R
0, D
3String D
4Be connected in BG
1Between base stage, emitter, D
5String D
6Be connected in BG
2Between base stage, emitter, C
12Be connected in D
PGo into end and E
0Between, D
32String D
42Be connected in BG
12Between base stage, emitter, C
F, F, R
FXiang Binglian, company and E
+With R
2Between, FG
GString R
5Be in parallel FG with J
YString R
6Be connected in E
+, E
0Between; HA and J
2KBe parallel to E
+With J, J
2Between, becoming and close a floodgate and the automatic reclosing loop, TA is connected in BG
22Base stage and E
0Between, become operation tripping operation and reclosing and remove the loop.R
MFCan be installed in the motor windings, on the motor housing, R
MBIt is contiguous to be loaded on motor bearings; R
MF, R
MBAll can by several thermistors and or the series connection and form.R
MF, R
MBAdopt negative tempperature coefficient thermistor (NTC); If using semistor (PTC) instead then should be with R among Fig. 1
MFWith R
W3Location swap (the R of disjunct two ends in circuit
MFMeet E
0, R
W3Meet E
+ 2), R
MBWith R
WBAlso this.(each 3 utmost point pipe is NPN3 utmost point pipe; If use PNP3 utmost point pipe then b, c, e invariant position instead entirely, other element of positive-negative polarity is respectively arranged, promptly 2 utmost point pipes, voltage stabilizing 2 utmost point pipes, luminous 2 utmost point pipes, electrochemical capacitor revert all are assemblied in the circuit and get final product.In addition, R
MFAlso can divide 3 to introduce R mutually
7+ R
70Also can change potentiometer into).
Fig. 2, Fig. 3 are respectively the corresponding 1 secondary circuit figure of Fig. 1 embodiment, contactor closing circuit figure, wherein C
1Be C phase mains side, A
2, C
IBe respectively the motor inlet wire of A, C phase, D is a motor, J
KBe the normal opened contact of J, CJ is the pull-in winding of A.C. contactor, CJ
2* 3 is 3 main contacts of A.C. contactor.LH
11Be LH
11 side.
By the whole system of Fig. 1, Fig. 2, the common embodiment that forms of Fig. 3, its operation principle is as follows:
Closed K
2E then
+, E
0Charged, normal condition G
1Base stage and BG
12The equal fault-free signal input of base stage, so blocking-up, their collector electrode is high potential, then electric current is through FG
R, R
1, R
2, R
3, R
4, R
20To BG
2Base stage is through R
22, R
32To BG
22Base stage, BG
1, BG
2Conducting.J and J when pressing HA
2All adhesives, J
K, J
2KClosure makes the charged adhesive of CJ, CJ on the one hand
2* 3 closures, electric motor starting; J on the other hand
2KClosure makes J
2Even self-sustaining is the temporary transient dead electricity of J and make J
KDisconnect CJ
2* 3 disconnect, motor tripping operation, J
2KRemain closed motor automatic reclosing after fault will be disappeared and self-starting again, if motor is damaging, starting current significantly surpasses normal value, then by R in self-starting again
WKThe short circuit current signal of obtaining will pass through D
KTo BG
12Make its conducting, thereby make BG
22Blocking-up, J
2Dead electricity, J
2KDisconnect.J
2Self-sustaining is removed, and makes the J dead electricity again, J
KDisconnect, generation can't be tripped (because of J by self-running motor
2KDisconnected).Frequent self-starting, then this signal is from D
PDeliver to BG
12Make J
2KDisconnected.If have insulation, temperature, overvoltage fault, then above-mentioned signal is respectively from D before pressing HA
O, D
M, D
8Transport to BG
1Base stage makes BG
1Conducting, its collector potential are reduced to and are bordering on zero, make BG
2Base stage can't obtain electric current, BG
2Blocking-up, even press HA, J is no current still, (but J still can't close a floodgate
2KClosure can be started after fault is disappeared automatically), play the prevention protective effect.Motor is in service if overcurrent, temperature, bearing temperature, overvoltage fault take place, and then these signals are respectively from D
L, D
M, D
B, D
8To BG
1Conducting, BG
2Blocking-up, J dead electricity, J
KDisconnection causes the motor tripping operation, and (if the tripping operation back is fault-free J
2KMaintenance can cause self-starting), thereby the protection motor.When motor generation motor in service B phase short of electricity fault (A, C short of electricity; The B overcurrent), this signal is from R
W1Through D
dDeliver to BG
2Base stage is because of R
W1No electricity makes BG
2Base voltage descends, and makes BG
2Blocking-up, J dead electricity, motor tripping operation, CJ
K2Disconnection, this signal of locking before motor closes a floodgate are in order to avoid the motor fail to start; Brownout signal before motor closes a floodgate by D
9Deliver to BG
2Base stage is BG during under voltage just
2Blocking-up, closing operation can't realize that prevention protection motor when under voltage takes place is as the motor CJ by disconnection in service
B2This signal of locking.CJ
B1At motor combined floodgate (CJ
2Close) preceding closure, make the Insulation Test power supply enter B
2, locking E then after motor closes a floodgate
+With B
2Passage.HA
K2, HA
WK2By closing, E when motor is closed a floodgate
+Be able to directly to starting delay capacitor C
20Charging, CJ at this moment
K1Locking C
20Insert BG
2The contact of base circuit, with the obstruction free fault-signal to BG
2Influence; HA after motor closes a floodgate
K2, HA
WK2Unclamp (so motor C in service
20Can not be again from E
+Directly charging), CJ
K1Closed with C
20Insert BG
2Base circuit is with its more electric weight supply BG
2Base stage makes in this discharge process, can be because of D
LInput starting current, BG
1Conducting causes BG
1Collector potential descends, causes BG
2Base stage does not have sufficient current, causes BG
2Blocking-up, thus avoided motor to cause tripping operation because of normal starting; After motor starting process finishes to enter normal operation, C
20Because of the discharge after can not be again from E
+Charging no longer produces bigger time-delay (all then not producing time-delay after the discharge), makes BG if break down
1Collector potential descends, and then relies on C
2Discharge generation time-delay is significantly smaller than time-delay in the starting (in the starting by C so tripping operation in service is delayed time
2, C
20Time-delay is provided jointly).D
3, D
4, D
5, D
6, D
32, D
42, D
52, D
62, D
W1All play protection 3 utmost point pipes, D
7, D
72Protection relay transient state is removed C
2, C
20Electrochemical capacitor in addition all plays filtering (elimination alternating current component) effect.FG
R, FG
G, FG
Y, FGG
2Being shown with fault, motor rotation, power supply with light emitting sheet respectively has electricity, self-starting not to remove R
1, R
5, R
6, R
52Be respectively their current-limiting resistance.C
LBe LH
2Resonant capacitance.TA then makes BG if press
22Base stage and E
0Short circuit makes BG
2Blocking-up J
2Dead electricity, J
2KDisconnect, the J dead electricity, causing can not self-running motor tripping operation.
Fig. 4 is GB among the 1st kind of embodiment
1Replacement circuit, it by voltage comparator ic (1,2,3,4,5,6,7,8 is its 8 pin ,-,+represent negative, positive input respectively), reference voltage dropping resistor R
j, voltage-stabiliser tube D
W3, divider resistance R
8, R
9Form; By E
+Through R
j, voltage-stabiliser tube D
W3Provide reference power supply E to it
+ 3, G
1b, G
1eBG in the presentation graphs 1
1Base collector, emitter in Fig. 1 circuit, account for the position; 1 meets E
+, 4 meet E
0With the BG among Fig. 4 circuit replacement Fig. 1
1Promptly be to use voltage comparator as elementary amplifier element, fault-signal is by G
1bTo 2 with input 3 reference voltage relatively after, export G to by 1
1c(G
1bSignal is arranged, G
1cLow level makes BG
2Time-delay blocking-up tripping operation).Claim this embodiment the 1st kind of embodiment for comparator with voltage.(export the temperature coefficient of 2 utmost point pipes for offsetting each signal, reference voltage also can be imported to it " 3 " pin of IC and each reference voltage pin through 2 utmost point pipes again).
Fig. 5 is the 2nd kind of embodiment.Its operating power is by current transformer LH
2Power supply, LH
22 b
2, b '
2Through D
1* 4 rectifications, C
5Filtering becomes E
+, E
0Direct current operative power source.E
+, E
0By 16 2 utmost point pipe D
E* 16 series connection by the voltage stabilizing shunt circuit (or use by dotted line among the figure voltage stabilizing 2 utmost point pipe D of company
WVoltage stabilizing), this circuit and E
0Between be in series with the current signal sensor resistance R
U, by with R
UPotentiometer R in parallel
WRegulate current signal, by R
WThe moved end output current signal.At E
+, E
0Between by BG
1, BG
2And the structure of 2 grades of amplifying circuits forming of subsidiary component is identical with appropriate section among Fig. 1 embodiment (but does not have the R of starting delay circuit
W2, C
20, R
20, D
20, CJ
b, CJ
K1), the fault trip principle is also together; But J directly connects E
+, carry out motor combined floodgate, trip operation with protector outside, the original combined floodgate of motor, trip button.The 2nd kind of embodiment also can set up the temperature signal sensing circuit again.
Fig. 6 is 1 special case again of the 2nd kind of embodiment, and its operating power is by current transformer LH
1Power supply, LH
12 sides can be through rectification (also can without the i.e. not rectification of rectification-Fig. 6), to the thermal relay JR that is in series, current relay J
LThe supply power current signal of holding concurrently, and the normally closed contact RJ of RJ
b, J
LNormal opened contact J
LKThen be connected in series with in the A.C. contactor CJ closing circuit HA and J
LKParallel connection, TA connects with CJ.RJ deferred action makes RJ during overcurrent
bTime Delay Opening, make motor tripping operation; B phase short of electricity J
LDead electricity, J
LKDisconnect and make the motor tripping operation.This is that a kind of phase shortage that adopts thermal relay is transshipped simple and easy protector.
Fig. 7 is the 3rd kind of embodiment, and its operating power is powered by contactor pull-in winding CJ.CJ and operating power E
+, E
0Rectification circuit D
1* 4 are in series; CJ
B1, R
2, D
1* 4 are in parallel; The outside switch knob HA of the protector that is in parallel
W, J
K, the outer trip button TA of protector
WAll connect with CJ; Entire circuit is by B
1, C
IObtain line voltage, fuse RD is series at B
1Introduce on the circuit.At operating power E
+, E
0In the system, D
WBe voltage stabilizing 2 utmost point pipes, C
5For filter capacitor all is parallel to E
+, E
0Between; And the temperature signal sensing circuit, by BG
1, BG
2And the structure of 2 grades of amplifying circuits forming of subsidiary component, principle are also identical with appropriate section among the embodiment of Fig. 1, and (but time-delay is by R
MF, remove C
2, R
4, C
3, with 2 utmost point pipe D
34For D
3, D
4, or with D
W0For D
34Exempt from D
5, D
6, do not establish FG
R, R
2, FG
G, R
5).Present embodiment CJ
B1Locking D before combined floodgate
1* 4 and E
+, E
0System can guarantee that CJ obtains abundant voltage, and back CJ closes a floodgate
B1Disconnect and make D again
1* 4, E
+, E
0Drop into.The 3rd kind of embodiment also can set up current signal sensing circuit and delay circuit.
R among Fig. 7
2, CJ
B1, HA
W, J
K, TA
W, CJ is connected in E by changing shown in the dotted line
+, E
0, D
1* 4 output negative terminal E
-(disconnect E
0, E
-Line), former HA
W, J
K, AT
W, the CJ position changes crosstalk and holds C
C, CJ normally closed contact CJ
B4And connect combination, E
+With E
-Between increase crosstalk and separate capacitor C
2And CJ normal opened contact CJ
K3, then with CJ silent running function.
Fig. 8, Fig. 9 are two kinds of different types of the 4th grade of embodiment, and its operating power is by capacitor C
CThe step-down power supply, B
1With RD polyphone D
1* 4, connect C again
C, K
2To C
1Form operating power current supply circuit D
1* 4 direct current output E
+, E
-=E
0, E
+, E
0Between the circuit structure of direct current system, identical (1 E of principle with Fig. 7 embodiment
+, E
0Between FG
Y, R
6); But its motor switch is the disconnecting link switch, by the hollow breaking coil T that promotes the clavate iron core
xDrive tripping operation, the normally closed contact J of J
bBe connected in series with B electricity, T mutually behind the RD
xTo C
IThe loop in; When fault-signal causes J dead electricity, J
bClosed, T
xCharged and the disconnecting link switch is disconnected.Before motor disconnecting link switch closes a floodgate, drop into protection earlier, even K
2Closure, E
+, E
0Charged, J is charged, J
bDisconnect, disconnecting link just can close a floodgate like this, and can be because of T
xThe charged disconnecting link of pushing open immediately.Fig. 9 and the difference of Fig. 8 embodiment only be Fig. 9 have the current signal sensing circuit (it is identical with Fig. 1 embodiment appropriate section---but do not have R
WK, R
Wt, R
Wt2), Fig. 8 does not then have.Fig. 9 embodiment also can set up phase failure no-load signal sensing circuit.
Figure 10 is the another special of the 4th kind of embodiment, and the difference of it and Fig. 8 embodiment only is to have only BG
1, 1 grade of amplification is about to D
7, J is directly connected in E
+With BG
1Between the collector electrode, remove R
3, D
56, BG
2, C
4B
1Change B into
2, C
1Change C into
I, remove K from
2, short circuit it, J
bChange J into
KBG during fault
1Conducting J
KClosure make T charged, drive the disconnecting link tripping operation; If disconnecting link closes a floodgate fault-free J
KDisconnect (because of BG
1Blocking-up J dead electricity), T is not charged can not to trip.
T among Fig. 8, Fig. 9, each embodiment of Figure 10
x, be (to work as T through what guidance tape moving knife lock disconnected with rope
xWhen charged), also can drive automatic air-break switch tripping operation (if replacing disconnecting link as motor switch) with automatic air-break switch.
Figure 11, Figure 12 are with the insulation signal sensing circuit of alternating current as two kinds of embodiment of insulation test voltage, and they all can replace in Fig. 1 enforcement separately from E
+ 2, E
0Obtain the insulation signal sensing circuit of Insulation Test power supply.Among Figure 11, Figure 12, C
YBe electric capacity, R
Y1, R
Y2, R
Y3, R
Y4Be resistance, C
B0Be electrochemical capacitor, D
Y1, D
Y2Be 2 utmost point pipes; Except by D
0Transfer to the 1st the voltage comparison loop IC of IC
1, R
0, C
B0Be parallel to IC
1The 2nd pin and E
0Between outside, all the other elements all are series at B
2, CJ
B1With O
3, CJ
B3Between (but D
Y2Be parallel to D
Y1Go into end and E
0Between, R
Y2Be parallel to D
0Go into end and E
0Between).U
S1, U
S2Can be zero-power line O
1, B
1Also can be the 2 sub-high pressure sides (its 1 side links to each other with 2 sides of the transformer T of operating power) of testing transformer.The difference of Figure 12 and Figure 11 is that Figure 12 has increased by D
Y1, D
Y2The rectification circuit of forming.(O among Figure 11 and Figure 12
3, B
2The position all also can exchange mutually, but should make O
3Together with CJ
B3, C
YTogether with B
2With CJ
B1Exchange).
Figure 13, Figure 14 close a floodgate and the work tripping operation for adopting CJ, adopt automatic air-break switch DZ to carry out combined floodgate, the trip operation loop of fault trip embodiment; They can replace Fig. 3 and cooperate utilization with Fig. 1 embodiment.Figure 13 is for utilizing electromagnetic trip mechanism or breaking coil T
xMake the circuit of the situation employing of DZ tripping operation, Figure 14 is the circuit that utilizes no-voltage trip coil SY that DZ tripping operation situation is adopted.RD among Figure 13, Figure 14
x, RD
SBe respectively protection T
x, SY fuse.Figure 13 is by B
1, K
2, RD
x, TA
W, CJ, C
I, HA
W, C
I2Series connection, T
x, J
bConnect in parallel with CJ and TA again and form; Figure 14 is by B
1, K
2, TA
W, CJ, C
I, HA
W, C
I2Series connection, SY, RD
S, J
KBe in series again and HA
W, CJ, TA
WIn parallel and form; C
I2The C phase outlet side (load-side) of expression automatic air-break switch.HA
W, TA
WControl CJ; J among Figure 13 during fault
bClosure makes T
xCharged and cause DZ tripping operation, J among Figure 14 during fault
KDisconnection, SY dead electricity cause the DZ tripping operation.
Figure 15, Figure 16 close a floodgate for Fig. 1 embodiment adopts CJ, can overlap tripping operation, automatic reclosing, adopt DZ to carry out function circuit, the trip(ping) circuit that can not overlap tripping operation (fault and operation).Figure 15 is on the HA of Fig. 1 function circuit basis, and HA is changed to the 2nd couple of normal opened contact HA of outside switch knob
WK2, from J
2Normally closed contact J
2bNormally closed non-common port connect J
2, again to E
0, J among the figure
+, J
2+Expression J, J
2Anode; Figure 16 is by C
I, T
x, J
3Normal opened contact J
3K, RD
x, K
2, B
1Polyphone is formed mutually, works as J among Figure 15, Figure 16
2During dead electricity, J
2bClosed, J
3Charged, make J
3KClosed, cause T
xChargedly cause DZ tripping operation replacements such as () the also available automatic air-break switch DW of DZ.Figure 15, Figure 16 and Fig. 1 embodiment adapted (HA among Fig. 1
WK2With CJ
B3For it).
Figure 17 is changed to the trip(ping) circuit that SY trips for the T with Figure 16, and it is by B
1, K
2, J
3b, RD
S, SY, C
I2Be composed in series CJ normally closed contact CJ
B4With J
3bParallel connection, J
2Dead electricity, J
3Charged, J
3bDisconnect, the SY decompression causes the DZ tripping operation.Figure 17 also with Fig. 1 embodiment adapted.
Figure 18, Figure 19 are no CJ, have only the trip(ping) circuit circuit of DZ, Figure 18, Figure 19 structure, the same respectively Figure 16 of principle, Figure 17, but its J
3K, J
3bShould easily be J
b, J
K(because J
3With the J opposite states), they all can (but not have J with Fig. 1 embodiment adapted respectively separately
2, J
2K, CJ
B5).Figure 19 is the T with Figure 18
xThe trip circuit figure that changes SY into is (with T
x, J
bBe changed to S
Y, J
K), it can match with each embodiment of Fig. 1 to Figure 10.
Trip(ping) circuit when Figure 20 has only auto-transformer starter for motor switch only is B than the difference of Figure 19
1Become B
2, it also can match with each embodiment (but with J
KPolyphone T
xThe person should change into J
bSeries connection SY).
Operating power voltage stabilizing circuit when Figure 21 powers for transformer T.R
EBe resistance, R
7From R
EThe place ahead pressure.Figure 22 is R
W2Delay circuit during for doubly-linked.
The utility model is except taking to match with multiple different components, circuit (as Figure 11 to Figure 20) can suiting measures to local conditions aspect insulation test voltage, the motor switch; form outside the embodiment that is fit to different occasions; also can match, and form the embodiment that more is applicable to the multiple requirement of different user with the CJ silent running circuit, phase sequence circuit, Y-Δ commutation circuit, operating power voltage stabilizing circuit, constant time lag automatic reclosing circuit, the automatic cut-off circuit of underloading, doubly-linked push-botton operation circuit etc. that Figure 23 is Figure 37.Though Figure 23 to Figure 37 is not the essential characteristic of present embodiment, the circuit that they have with the present embodiment essential characteristic is combined into total system, more the effect of the essential characteristic that comprised of the filling performance latter; Therefore, they also are the attachment components of realizing the present embodiment essential characteristic.
Figure 23, Figure 24, Figure 25 are 3 kinds of different CJ silent running circuit, wherein before and not markedly newly be labeled as: C
W1Be electric capacity, D
WS* 4 is the bridge rectifier of 42 utmost point pipe compositions, C
W2Be electrochemical capacitor, T
WBe silent running transformer (also can unify, establish 2 groups of low pressure windings), D with T
WS1With D
WS2Be 2 utmost point pipes, RD
CBe fuse, TA
WBe outside trip button.
Figure 26, Figure 27 are Y-Δ commutation circuit, as motor Y-Δ starting and underloading by automatically switch usefulness (to save the electric energy of motor operation consumption) of Y of Δ; Wherein Figure 26, Figure 27 respectively with Fig. 1, Fig. 4 embodiment adapted (add Fig. 1, replace Fig. 4) with Figure 27 with Figure 26.Figure 28 is the 1 secondary circuit figure of Figure 26, Figure 27, and Figure 29 is the closing circuit figure of Figure 26, Figure 27.The front is not marked among Figure 26, Figure 27, Figure 28, Figure 29 is labeled as: BG
13, BG
23Be 3 utmost point pipes, R
Δ 1, R
Δ 2, R
Δ 3, R
B, R
WiBe resistance, C
Δ, C
Δ 1Be electrochemical capacitor, D
The L Δ, D
Δ, D
Δ 3, D
Δ 4, D
Δ 0Be 2 utmost point pipes, FG
B, FG
WBe luminous 2 utmost point pipes; BG
13, BG
23Be 3 utmost point pipes; CJ
Δ, CJ
YBe A.C. contactor, its main contact is respectively CJ
Δ 2 * 3(3 of 3 phases), CJ
Y2* 2 (3 mutually in 2); J
ΔBe relay, J
Δ b, J
Δ KBe respectively J
ΔNormally closed, normal opened contact; X, Y, Z are 3 tail ends of motor windings A, B, C3 phase.(Figure 29 also can: from CJ
Y, CJ
Δ, CJ removes the corresponding automatic air-break switch of break-make; Form Figure 28 circuit by the latter).
Figure 30 is the automatic reclosing circuit of constant time lag, and the not marked mark SJ in front, ZJ are respectively the time relay, auxiliary relay, ZJ among the figure
KBe the normal opened contact of ZJ, HK is the tripping operation control switch that closes a floodgate (tripping operation is for overlapping tripping operation).As with dashed lines circuit connected device spare not without ZJ then adopts HK; If adopt ZJ, then with dashed lines circuit and TA, HA, ZJ, ZJ without HK
KFigure 31 is corresponding 2 secondary circuits of Figure 30, wherein J
+Positive potential end for relay J; J
+Normal opened contact SJ by the SJ that is in parallel
K(should be timing closing, time-delay disconnection), CJ
K1With E
+Link to each other.If adopt Figure 30, Figure 31 circuit, then if Fig. 1 embodiment cooperates with it and can save R
Wt2With J
2SJ
KThe timing closing time should be obviously greater than 7 times of electric motor starting time." impermanent tripping operation is coincidence signal not ": can be by ZJ
KNon-B side is drawn by CJ
bThe line of locking, through annunciator to C
1(if by J
2Overlap then by J
+Draw with CJ
bThe line of locking arrives E through annunciator
0); The little time-delay (exchanging then first rectification) that should have series resistance, associated capacitance to cause.
Figure 32 is light moving automatic cut-off circuit, wherein R
B12, R
42Be resistance, D
CCBe 2 utmost point pipes; If Fig. 1 embodiment cooperates with it and can save R
Wt2With J
2, BG
12Base stage is passed through R
B12Connect E
+, BG
22Collector electrode (the former J that connects
2-Point) changes even G
1cAdopt Figure 32 circuit then not adopt J
2Self-starting but can be adopted the self-starting of Figure 30, Figure 31, but SJ
KThe time of timing closing should be obviously greater than underloading excision time-delay.(R when using Figure 32
32, R
42All can be about 150K R
B12Can be about 30K), and HA, HA
WShould be again and CJ
K1Parallel connection, former CJ at this moment
K1Use other CJ
K).
Figure 33 singly connects the push-botton operation circuit for using; CJ among the figure
K4For the normal opened contact of CJ, with CJ
B3Replace HA
K2To C
20Charging is with CJ
B3Locking "on" position E
+With C
20Contact, no longer use the doubly-linked button.When CJ often opens, can add when normally closed contact is not enough 1 pull-in winding auxiliary CJ in parallel with the CJ pull-in winding or auxiliary ZJ; If the CJ coil current is bigger, (or ZJ removes break-make CJ then can to assist CJ, but can utilize auxiliary CJ or the normally closed contact of ZJ and the normally closed normal opened contact of CJ this moment, if contact is still not enough, then CJ also will another auxiliary CJ in parallel again or ZJ (or by the CJ break-make latter with the latter's normal opened contact).(when CJ often opens, normally closed contact is not enough when not intending expanding again, Figure 33 must be changeed back and use HA
K2, HA
WK2Replaced C J
B3, and use HA
B2String HA
Wb2Replaced C J
K4The CJ that vacates
K1, can be used for the constant time lag automatic reclosing or do not have when overlapping automatically and HA, HA
WIn parallel; But with HA
Wb2For CJ
K4To bring abnormal state can be continuously closing function by force, be interrupted and then still can not close by force).
The utility model not only can be protected low voltage motor, also can: be applied to the protection of electric welding machine, transformer, electrical equipment and high-voltage motor, economize on electricity.The utility model can be used for AC and DC, single, 3 phase systems (current transformer can be 11 mutually, or 33,4 or 32 mutually mutually---independence, differential, parallel connection); Direct current machine is then obtained current differential signal or is flowed signal (E with the magnetosensitive device power taking with resistance pressure reduction
+Get with resistance, voltage-stabiliser tube).
If the utility model is used for high-voltage motor (voltage is 3KV~6KV or high voltage more), then automatic air-break switch should be high-voltage switch gear (or high-tension oil switch), or adopts A.C. contactor control high-voltage switch gear; Current transformer can be with 11 or 22 or 33 (exporting 2 utmost point pipes with various current signals separately respectively imports to amplification control circuit) mutually mutually mutually; Each transformer can adopt 380V or 220V power supply; In addition, also can increase the preface signal wave current sensing circuit of high pressure temperature signal sensing circuit as Figure 34 (band inverse time lag circuit) and Figure 35.The front is not marked among Figure 34 is labeled as: T
3, T
GBe transformer (T
3Be stabilized voltage power supply), D
G* 4 is the bridge rectifier of 42 utmost point pipe compositions, R
G, R
T0Be resistance, C
G, C
MtBe electrochemical capacitor, R
Mt, R
WG, R
WGK, R
Mt0Be potentiometer (transferring in the back 3), D
Mt, D
MK, D
8tBe 2 utmost point pipes, T
GBe loaded on the near (T of connection box for motor
GIron core grounding, two windings divide stem stem, the same high-voltage motor of the class of insulation); Figure 34 removes R
MF, T
GRemainder, Figure 34 all can be assemblied in shell separately separately, also can unify to be assemblied in the motor protecter.The front is not marked among Figure 35 is labeled as: 1 grade of B phase, C phase, zero sequence current mutual inductor are LH
1B, LH
1C, LH
10LH
2b, LH
2CBe 2 grades of B, C phase current mutual inductor; R
1b, R
4C, R
WB, R
WCBe potentiometer, R
2b, R
E1, R
E2Be resistance, X
3CFor electric capacity (makes R
Ib=R
4C=R
2b R
4CAngle modulation, R
1bAmplitude modulation is to eliminate forward-order current); D
Φ, D
-1, D
-2, D
-, D
L-, D
K-, D
01, D
02, D
00, D
LO, D
KOBe 2 utmost point pipes, C
Φ, C
-, C
1-, C
OO, C
10Be electrochemical capacitor, R
W-, R
WO, R
-t, R
K-, R
Ot, R
KO, R
μ Φ, R
μ-, R
μ OBe potentiometer (except that first three, being generally interior accent), μ
Φ, μ
-, μ
0Be galvanometer (being generally microammeter).Figure 35 can be used as a specific installation, exports 1 time, 2 times, 3 primary current signal (μ
+, μ
-, μ
0), fault display signal (D
Φ, D
-, D
OO), deferred action signal (D
L, D
L-, D
LO), go back break signal (D
K, D
K-, D
KO).And μ
Φ, μ
-, μ
0With R
μ Φ, R
μ-, R
μ 0And D
Φ, D
-, D
OOConnect display circuit " (to special-purpose BG and luminous 2 utmost point pipes) can do ordering signal wave current display separately and (contain BG
1The PNP total failare signal of starting), also they all can be assemblied in the motor protecter.(negative-sequence current is adjusted and is taken as 0.2~0.4 times of motor rated current); (simple and easy preface signal wave current transducer can be with D
B, D
C, D
-2, D
0With D
2* 4 (or halfwave rectifier D
2Output) output be in parallel, and with D
B, D
C, D
-2, D
0The former institute of output connection circuit part is all removed, but D
-1Change potentiometer into, its moved end links to each other with quiet end.Figure 36 is other a kind of preface signal wave current transducer, wherein D
LA, D
LB, D
LC, D
L+Be 2 utmost point pipes, R
A, R
B, R
C, R
2C, R
Ao, R
Bo, I
CoBe resistance, X
4b, X
4CBe electric capacity, R
3b, R
3C, R
1C, R
W+, R
W-, R
WABe potentiometer, T
a, T
b, T
cBe current signal transformer, LH
1ABe 1 grade of A phase current mutual inductor, if LH
1A, LH
LCFor current mutual inductor with high transforming ratio then can be with R
A, R
B, R
CChange potentiometer into and omit T
a, T
b, T
c(the former circuit that connects their secondary directly meets R
A, R
B, R
C, R
A, R
B, R
CPress the variable resistor connection); In addition, if no LH
1AThe time, also can be with LH
1B, LH
1CI is passed through on former limit
B-I
C, I
C-I
AWith elimination zero sequence ripple.(also can be with R
1b, R
1cThe sound end separates, with 1 side of both sides, the moved end R that holds concurrently
2b, R
2c).
The utility model stands on the prior art; both had unique feature; the advantage of comprehensive similar technology again; and be to give full play to its feature, advantage according to diversified demand combinations; make every effort to advanced and the unified various embodiments of economy; thereby a kind of applicability is very big, technical-economic index optimization is strong for electric motor protecting provides, thereby by the enormously potential technology of practice.Its different embodiment can be used for medium and small and large-size machine, and low pressure and high-voltage motor (switch becomes high-voltage switch gear) exchange and direct current machine, motor and generator.Certainly, its applicability, superiority remain certain limit, certain limit is arranged, certain epochal character is arranged, and exceeds these boundaries, then still awaits the appearance of advanced new technology more of electric motor protecting technical field.
Claims (7)
1. motor protecter, it is by operating power, signal sensing circuit, the control amplifying circuit, relay is formed, and it is one of following 4 kinds that the operating power that it is characterized in that it can be: or use transformer-supplied, and at this moment its signal sensing circuit comprises the current signal sensing circuit at least, the temperature signal sensing circuit, the insulation signal sensing circuit that is linked to be by the divider resistance of the auxiliary normally closed contact of Insulation Test power supply, motor main switch, motor housing, 1 end of incoming cables of motor, current-limiting resistance, output signal; Or 2 side power supplies of Current Transformer, at this moment its signal sensing circuit comprises the current signal sensing circuit at least; Or with the pull-in winding power supply of the contactor of motor, at this moment its signal sensing circuit comprises the temperature signal sensing circuit at least; Or with powering behind the capacitance decompression, at this moment its signal sensing circuit comprises current signal sensing circuit or temperature signal sensing circuit at least; The dc output end of its operating power and control, amplifying circuit with just, the zero potential end links to each other; Its each signal sensing circuit is exported 2 utmost point pipes by signal separately respectively and is linked to each other with control, input amplifier; The pull-in winding of relay links to each other with control, amplifying circuit and output, and the contact of relay is connected among the loop of control motor main switch break-make.
2. motor protecter according to claim 1 is characterized in that, the operating power with transformer-supplied according to claim 1 is made up of transformer and rectification circuit; The operating power of 2 sides of Current Transformer power supply is by 2 sides of current transformer and rectification circuit, and the current signal resistance that 2 utmost point pipe series combination or voltage-stabiliser tube, series connection are with it shunted in the voltage stabilizing that is parallel to rectification circuit output end is formed; Operating power with the pull-in winding power supply of the contactor of motor is in series by contactor pull-in winding and rectification circuit, and rectification circuit input end also is in parallel with the contactor normally closed contact.
3. motor protecter according to claim 1 is characterized in that, current signal sensing circuit according to claim 1 is obtained signal by 1 grade or 2 grades of current transformers; The temperature signal sensing circuit is made up of humid test power supply, thermistor or other temperature-sensitive elements; Temperature-sensitive element can be loaded on motor coil, motor housing, motor bearings vicinity; Each current signal, temperature signal sensing circuit have Signal Regulation potentiometer separately respectively.
4. motor protecter according to claim 1 is characterized in that Insulation Test power supply according to claim 1 both can be obtained by direct current operative power source; Can obtain through electric capacity, resistance step-down current limliting by AC power again; Also can be got by 2 sub-high pressure side-draws of Insulation Test transformer, 1 side of this transformer links to each other with 2 sides of operating power transformer; Humid test power supply according to claim 3 by direct current operative power source through the resistance step-down; Obtain after the voltage-stabiliser tube voltage stabilizing.
5. motor protecter according to claim 1; it is characterized in that; control according to claim 1, amplifying circuit comprise the two-stage amplifying circuit at least; the input amplifier element of elementary amplifying circuit can be 3 utmost point pipe or voltage comparators, and the amplifier element of final stage power amplification circuit is 3 utmost point pipes.
6. motor protecter according to claim 1; the contact that it is characterized in that relay according to claim 1 is connected among the loop of control motor main switch break-make; both can be in the pull-in winding loop of 1 docking point of the relay contactor that is connected in series with motor; 1 docking point that can be relay again is connected in series with in the no-voltage trip coil or closing coil loop of starting switchs such as automatic air-break switch or auto-transformer starter; 1 docking point that can also be relay is connected in the shunt opening trip coil or breaking coil loop of automatic air-break switch, also can be that 1 docking point of relay is connected in series with in the breaking coil loop that drives the disconnecting link switch.
7. motor protecter according to claim 1 is characterized in that according to claim 6ly, is connected in series with by relay 1 docking point among the loop of pull-in winding of contactor of motor, and this contactor both can be directly with the alternating current adhesive; Again can the direct current adhesive, when with the direct current adhesive, can add the DC operation circuit of forming by this contactor normally closed contact, 2 utmost point pipes, electric capacity or electric capacity and transformer.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN 96231053 CN2255690Y (en) | 1996-01-12 | 1996-01-12 | Electric motor protector |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN 96231053 CN2255690Y (en) | 1996-01-12 | 1996-01-12 | Electric motor protector |
Publications (1)
Publication Number | Publication Date |
---|---|
CN2255690Y true CN2255690Y (en) | 1997-06-04 |
Family
ID=33908325
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN 96231053 Expired - Fee Related CN2255690Y (en) | 1996-01-12 | 1996-01-12 | Electric motor protector |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN2255690Y (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN101010847B (en) * | 2004-10-21 | 2010-12-01 | 肖普瓦克公司 | Method and apparatus for preventing overheating in an electronically commutated motor assembly |
CN108649530A (en) * | 2018-07-11 | 2018-10-12 | 安徽华茂纺织股份有限公司 | A kind of threephase motor temperature control light current and forceful electric power isolation circuit |
-
1996
- 1996-01-12 CN CN 96231053 patent/CN2255690Y/en not_active Expired - Fee Related
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN101010847B (en) * | 2004-10-21 | 2010-12-01 | 肖普瓦克公司 | Method and apparatus for preventing overheating in an electronically commutated motor assembly |
CN108649530A (en) * | 2018-07-11 | 2018-10-12 | 安徽华茂纺织股份有限公司 | A kind of threephase motor temperature control light current and forceful electric power isolation circuit |
CN108649530B (en) * | 2018-07-11 | 2024-04-09 | 安徽华茂纺织股份有限公司 | Temperature control weak current and strong current isolation circuit of three-phase motor |
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Legal Events
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---|---|---|---|
C14 | Grant of patent or utility model | ||
GR01 | Patent grant | ||
C19 | Lapse of patent right due to non-payment of the annual fee | ||
CF01 | Termination of patent right due to non-payment of annual fee |