CN2385458Y - Protective switch for electric machine - Google Patents
Protective switch for electric machine Download PDFInfo
- Publication number
- CN2385458Y CN2385458Y CN 98208653 CN98208653U CN2385458Y CN 2385458 Y CN2385458 Y CN 2385458Y CN 98208653 CN98208653 CN 98208653 CN 98208653 U CN98208653 U CN 98208653U CN 2385458 Y CN2385458 Y CN 2385458Y
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- Prior art keywords
- circuit
- electrically connected
- voltage
- output
- circuit unit
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Abstract
The utility model relates to a protective switch for electric machines, which is especially suitable for an electric system in countryside and a protector of a motor for a well pump. The utility model comprises a case and a circuit breaker. The utility model is characterized in that the utility model is provided with a motor protection control circuit which can control the operating state of shunted exciter tripping coils of the circuit breaker. The circuit is formed by the combination of an electromagnetic induction current-to-voltage converter, a sampling circuit unit, a signal processing unit, a stabilized power supply circuit unit, nor gate circuit unit, a delay antijamming circuit unit, a power circuit unit, a thyristor, a tripping power supply for the circuit breaker, etc. When the utility model is used, the utility model can ensure that high performance of the motor with loads can be exerted under a bad working condition, and effective protection can be obtained.
Description
The utility model relates to a kind of motor protecting switch, and a kind of safety guard that the well pump motor is used in the rural power system that is suitable for particularly is provided.
Current in the rural power electric power system, because the increasing sharply of rural electricity consumption equipment, cause the supply transformer off-capacity, line voltage is low, fluctuating range is big, voltage is seriously uneven between the three-phase electricity, the phase failure, overcurrent and the well pump motor that causes loses.And rural area well pump motor generally adopts knife switch to cooperate the fuse across-the-line starting at present; the magnetic starter that perhaps has thermal relay is as motor protecting switch; the defective that exists be often take place the phase failure or because of brownout can not normal starting; more can not reliable and effective protection motor, and increased hidden danger.
The purpose of this utility model is to provide a kind of well pump motor protecting switch in the rural power electric power system that is applicable to; with the defective of gram prior art, be implemented in the rural power system because of making the well pump motor obtain reliably, protect effectively under the situations such as the phase failure, line voltage shakiness, overcurrent.
The technical scheme that adopts that achieves the above object is: this motor protecting switch, include the circuit breaker that between three phase network and load motor, is electrically connected that is provided with in casing and the casing, it is characterized in that also being provided with in the casing electric motor protecting control circuit of control circuit breaker shunt opening trip coil operating state, this electric motor protecting control circuit has in the three-phase electricity of being separately positioned on arbitrarily on the two-phase and the identical induction current-to-voltage converter of two-way; The sample circuit unit that constitutes by the two paths of signals sample circuit; The signal processing unit that the two-way comparison circuit constitutes; And voltage-stabilized power supply circuit unit; One end of two outputs of wherein every road current-to-voltage converter is electrically connected on the signal input part of comparison circuit through sample circuit, and end is electrically connected on the thresholding input of comparison circuit through voltage-stabilized power supply circuit in addition; The output of two-way comparison circuit is electrically connected with the delay anti-jamming circuit unit through the OR-NOT circuit unit, delay anti-jamming circuit unit output is electrically connected with power amplifier unit and load SCR control end thereof, controllable silicon is by the circuit breaker trip power supply power supply that is connected in the three-phase electricity that circuit breaker is connected with load motor, and the controllable silicon output is electrically connected with the shunt opening trip coil of circuit breaker.
The purpose of this utility model is to provide a kind of well pump motor protecting switch in the rural power electric power system that is applicable to; with the defective of gram prior art, be implemented in the rural power system because of making the well pump motor obtain reliably, protect effectively under the situations such as the phase failure, line voltage shakiness, overcurrent.
Fig. 1 is this motor protecting switch outline drawing.
Fig. 2 is the organigram of this motor protecting switch.
Fig. 3 is the electric functional-block diagram of this motor protecting switch.
Fig. 4 is the circuit diagram of this motor protecting switch.
The embodiment that bears below in conjunction with accompanying drawing further describes.
This motor protecting switch outline drawing that ginseng electrograph 1 provides, it includes to be equipped with on circuit breaker (2), the casing (1) in casing (1), the casing (1) and also is fixed with binding post (3).
Referring to Fig. 2, the electrical network three-phase electricity inserts three power input A ' B ' C ' of circuit breaker (2) respectively by A, B, C, three binding posts of binding post (3), and the A of electrical network three-phase electricity, B two phase conductors are respectively as current-to-voltage converter (I simultaneously
1) and (I
2) in a winding of iron core (4), (5), be about to A, B two phase conductors respectively in the window of iron core (4), (5); Also be wound with secondary winding (L on iron core (4), (5) respectively
1), (L
2), the lead termination of secondary winding is respectively as current-to-voltage converter (I
1), (I
2) output be electrically connected with electric motor protecting control circuit board (6), circuit board (6) is provided with the electric motor protecting control circuit, the output of this control circuit is electrically connected in the shunt opening trip coil (L of circuit breaker
T).
Referring to Fig. 3, this motor protecting switch circuit comprises the circuit breaker (2) that is electrically connected between electrical network three-phase conducting wire A, B, C and the load motor (7), and this circuit breaker (2) can adopt commercially available DZ15LD, DZ15 series of products; Comprise two identical induction current-to-voltage converter (I that are arranged on three-phase A, B two-phase
1) (I
2); Comprise voltage-stabilized power supply circuit unit (II); Comprise by two same signals sample circuit (III
1) (III
2) the sample circuit unit that constitutes; Comprise by the identical comparison circuit (IV of two-way
1) (IV
2) signal processing unit that constitutes; Also comprise OR-NOT circuit unit V, delay anti-jamming circuit unit (VI), power amplifier unit (VII) and load controllable silicon (SCR) thereof; Also include circuit breaker trip power supply (VIII).
Referring to Fig. 4.Voltage-stabilized power supply circuit unit (II) is made of following structure among Fig. 3: the B phase current voltage changer secondary winding L of electrical network three-phase electricity
1With by diode D
5, D
6, D
7, D
8The rectifier bridge of overlap joint is electrically connected; The secondary winding L of A phase
2With by diode D
9, D
10, D
11, D
12The rectifier bridge of overlap joint is electrically connected; Be electrically connected resistance R after the two rectification bridge output end parallel connections
5, voltage-stabiliser tube DW
1, capacitor C
1Constitute one time direct current regulation circuit; Direct current regulation circuit again with integrated package of pressure-stabilizing IC
1, capacitor C
2Provide voltage-stabilizing working power supply for each circuit unit after the voltage stabilizing of connection realization secondary successively.Signal processing unit is by the identical comparison circuit IV of two-way among Fig. 3
1, IV
2Constitute, the two-way comparison circuit adopted commercially available 239 or the integrated package of 339 models in IC
3, IC
4Reach the peripheral circuit overlap joint and form, wherein comparison circuit IV
1By IC
3And resistance R
6, R
7, R
8, R
9, R
10, R
11, RW
1, capacitor C
3, diode D
13Overlap joint forms, comparison circuit IV
1Thresholding input by IC
1Output is through resistance R
7, RW
1, R
9Be connected in IC after the dividing potential drop
3Pin 11, pin 8 provide; Comparison circuit IV wherein
2By IC
4And R
12, R
13, R
14, R
15, R
16, R
17, RW
2, diode D
14, capacitor C
4Overlap joint forms, comparison circuit IV
1Thresholding input by IC
1Output is through resistance R
12, RW
2, R
13Be electrically connected on IC after the dividing potential drop
4) pin 4, pin 7 provide.The sample circuit unit is by two same signals sample circuit III among Fig. 3
1III
2Constitute, wherein signal sample circuit III
1Comprise and be electrically connected on A phase secondary winding L
2On two diode D
1, D
2, and utilize by diode D
9, D
10, D
11, D
12The D of the rectifier bridge of overlap joint
9, D
10The signal sampling rectifier bridge that two brachium pontis overlap joint forms and this rectifier bridge output be electrically connected by resistance R
1, R
2The voltage divider that constitutes constitutes; Signal sample circuit III wherein
2Comprise by being electrically connected on B phase secondary winding L
1On two diode D
3, D
4, and utilize by diode D
5, D
6, D
7, D
8The D of the rectifier bridge of overlap joint
5, D
7The signal sampling rectifier bridge that two brachium pontis overlap joint forms and this rectifier bridge output be electrically connected by resistance R
3, R
4The voltage divider that constitutes constitutes, in resistance R
1, R
2In the voltage divider that constitutes by resistance R
1, R
2Centre tap be electrically connected resistance R
6Be IC
3Sampled signal is provided; In resistance R
3, R
4In the voltage divider that constitutes by resistance R
3, R
4Centre tap be electrically connected resistance R
14Be IC
4Sampled signal is provided.OR-NOT circuit unit (V) is by transistor T among Fig. 3
1And resistance R
18, R
19, diode D
13, D
14Form, its input inserts IC respectively
3, IC
4Output.Delay anti-jamming circuit unit VI comprises triode (T among Fig. 3
2), its emitter grounding, its base stage connects voltage-stabiliser tube DW successively
2, resistance (R
21) after be connected in the output of a direct current regulation circuit, its collector electrode is connected to electric capacity (C over the ground
5); Has photoelectrical coupler IC
2, IC
2One end (pin 1) the AND circuit output end of middle luminous tube is a transistor T
1Collector electrode be electrically connected, end (pin 2) is through resistance R in addition
20Ground connection; Photosensitive tube one end (pin 4) of photoelectrical coupler is through resistance R
21Connect the output of a direct current regulation circuit, end (pin 3) meets triode (T in addition
2) collector electrode, T
2Collector electrode through voltage-stabiliser tube DW
3In be electrically connected with power amplifier unit input.Power amplifier unit VII among Fig. 3 is by transistor T
3And resistance R
22Constitute, its base stage is electrically connected voltage-stabiliser tube DW
3, its emitter-base bandgap grading is through resistance R
22Be electrically connected on the control end of controllable silicon SCR.Controllable silicon can adopt commercially available BT series of products among Fig. 3.The output of controllable silicon SCR is electrically connected with the shunt opening trip coil (LT) of circuit breaker (2).Circuit breaker trip power supply shown in Fig. 3 is by four diode D
15, D
16, D
17, D
18Be connected to three-plase half wave rectifier circuit and constitute, wherein by electrical network A phase conductor, the D that just advancing to bear out
15, bear the D that is into just going out
16, bear the D that is into just going out
17, the D that just advancing to bear out
18, be electrically connected successively to the C phase conductor; By D
15With D
16Between tap be electrically connected with the anode of controllable silicon SCR; By D
16With D
17Between tap be electrically connected with the B phase conductor; By D
17With D
18Between tap be electrically connected with the output of controllable silicon SCR through the shunt opening trip coil of circuit breaker (2).Each electric elements is seen detail list among Fig. 4.
Referring to Fig. 4 and Fig. 1, this motor protecting switch operation principle and process are as described below.Referring to Fig. 1, when using this product, electrical network three-phase electricity A, B, C lead are inserted three binding posts of A, B, C of binding post (3) respectively, three leads of load motor (7) are inserted three binding posts of U, V, W of binding post (3), the switch of manual closing circuit breaker shown in Figure 1 (2), then motor rotation work.Below referring to Fig. 4, a kind of situation is, as electrical network three-phase electricity A, when B, C all have electricity and normal power supply, L
1, L
2All electric, D
5～D
8And D
9～D
12Two rectifier bridges all electric, voltage stabilizing circuit unit (II) work, two-way sample circuit III
1And III
2All electric work, respectively sampled signal is delivered to IC
3Pin 3, pin 9 and IC
4Pin 6, pin 5, (determine thresholding according to load motor (7) watt level) because of sampled signal this moment in the thresholding zone, make IC
3Pin 13, pin 14 and IC
4Pin 1, pin 2 all be high potential, then T
1Carry and end IC
2Middle not conducting of light-emitting diode (not luminous), IC
2Pin 4, pin 3 not conductings, DW
2Conducting, T
2Conducting, T
2Collector potential is zero, T
3Open circuit by, controllable silicon SCR Triggerless, LT, the switch (K) of circuit breaker (2) is closure state, and motor runs well.Second kind of situation be electrical network A mutually with B in mutually during the arbitrary phase phase failure, then IC
3And IC
4Sampled signal surpass thresholding, then IC at its signal input part place
3And IC
4Output pin 4 and pin 1 or output pin 13 and pin 12 upset (transferring electronegative potential to), then T by high potential
1Transfer conducting, IC to by ending
2Light-emitting diode work, its photosensitive tube conducting, DW
2Shutoff, T
2Carry and end C
5Through R
21Cause DW after the charging time-delay
3Conducting, T
3Conducting, it is electric that SCR triggers, makes LT formation loop to get, and electric network source is cut off in then killer switch (K) tripping operation, and motor is quit work, and reaches the purpose of the power-off protection of protection motor (7).The third situation is when the phase failure of C phase, causes charged A, B phase overcurrent, and sampled signal surpasses the comparison circuit thresholding, and the upset of comparison circuit output pin makes T
3Conducting triggers SCR, makes L
TMust be electric, switch (K) the tripping operation outage of circuit breaker (2), load motor (7) dead electricity reaches the protection purpose.The 4th kind of situation is to cross low and the machinery card is stifled when causing motor rotation blockage and causing over current of motor because of line voltage, and wherein A, B two-phase sampled signal are all greater than thresholding, and SCR is triggered, L
TMust be electric, make the K tripping operation, reach the purpose of over current of motor protection.The course of work of delay anti-jamming circuit unit is: when electric motor starting momentary excess current, line voltage momentary fluctuation, and exist under other disturbed condition, if disturb for instantaneous interference (as interference time less than 5 seconds), after interference signal disappears, T
1Transfer to by conducting and to end C
5Both end voltage is not enough to DW
3Conducting, T
3Still be in cut-off state, L
TOpen circuit, circuit breaker (2) keeps "on" position, load motor (7) runs well, reaches the anti-interference purpose of time-delay.Interference signals disappearance, T less than 5 seconds
1By, IC
2Pin 4 is high potential, DW
2Conducting, T
2Conducting, C
2Pass through T
2Collector electrode and base stage are discharged rapidly.
This motor protecting switch has following advantage: 1, owing to adopted current-to-voltage converter and two technological means of circuit breaker trip power supply; make load motor (7) under the mains supply brownout and the bigger operating mode that fluctuates; can give play to maximum efficiency, and be effectively protected.2, owing to adopted the technological means of delay anti-jamming circuit unit, can eliminate the caused circuit breaker misoperation of any interference signal, protect the normal operation of motor (7).3, if the transformer load side motor in the power supply grid system then can ensure the safe operation of supply transformer when all adopting the utility model.4, owing to adopt the technological means of circuit breaker, load-side phase fault and one-phase ground protection have been realized.
The electric elements detail list
| Code name | Title | Specification and model | Quantity | |
| L 1-L 2 | Secondary winding | Self-control 5VA (342 circle) | 2 | |
| D 1-D 18 | Diode | lN4007 | 18 | |
| C 1 | Electrochemical capacitor | 50V/470μF | 1 | |
| C 2 | Electrochemical capacitor | 25V/470μF | 1 | |
| C 3-C 4 | Electrochemical capacitor | 25V/3.3μF | 2 | |
| C 5 | Electrochemical capacitor | 50V/ | 1 | |
| IC 1 | Integrated circuit | LM7812 | 1 | |
| IC 2 | Photoelectrical coupler | PC817 | 1 | |
| IC 3，IC 4 | Integrated circuit | LM339 | 1 | |
| T 1 | Triode | C3906 | 1 | |
| T 2-T 3 | Triode | C1008 | 2 | |
| DW 1 | Voltage stabilizing didoe | | 1 | |
| DW 2 | Voltage stabilizing didoe | 1/ | 1 | |
| DW 3 | Voltage stabilizing didoe | 1/2W5.2V | 1 | |
| R 1-R 4 | Resistance | 1/8W510K | 4 | |
| R 2 | Resistance | 2W300Ω | 1 | |
| R 6，R 14 | Resistance | 1/8W68K | 2 | |
| R 7，R 8 | Resistance | 1/8W3.3K | 2 | |
| R 9，R 13 | Resistance | 1/8W5.1K | 2 | |
| R 10，R 11 R 15，R 16 | Resistance | 1/8W1K | 4 | |
| R 8，R 17 | | 1/8W51K | 2 | |
| R 18 | | 1/8W5.6K | 1 | |
| R 19 | Resistance | 1/8W33K | 1 | |
| R 20 | Resistance | 1/8W510Ω | 1 | |
| R 21 | Resistance | 1/8W680K | 1 | |
| R 22 | Resistance | 1/8W5.1K | 1 | |
| R 23 | Resistance | |||
| RW 1，RW 2 | | 1W10K | 2 | |
| LED | Light-emitting diode | 1 | ||
| V | Voltmeter | 82L10-450V | 1 | |
| K | Circuit breaker | DZ15LD (DZ15) | 1 |
Claims (6)
1, a kind of motor protecting switch, include the circuit breaker that between three phase network and load motor, is electrically connected that is provided with in casing and the casing, it is characterized in that also being provided with in the casing electric motor protecting control circuit of control circuit breaker shunt opening trip coil operating state, this electric motor protecting control circuit has in the three-phase electricity of being separately positioned on the two-phase arbitrarily and the identical induction current-to-voltage converter of two-way, the sample circuit unit that is made of the two paths of signals sample circuit, signal processing unit that the two-way comparison circuit constitutes, and voltage-stabilized power supply circuit unit; One end of two outputs of wherein every road current-to-voltage converter is electrically connected on the signal input part of comparison circuit through sample circuit, and end is electrically connected on the thresholding input of comparison circuit through voltage-stabilized power supply circuit in addition; The output of two-way comparison circuit is electrically connected with the delay anti-jamming circuit unit through the OR-NOT circuit unit, delay anti-jamming circuit unit output is electrically connected with power amplifier unit and load SCR control end thereof, controllable silicon is by the circuit breaker trip power supply power supply that is connected in circuit breaker and load motor link three-phase electricity, and the controllable silicon output is electrically connected with the shunt opening trip coil of circuit breaker.
2, motor protecting switch according to claim 1, it is characterized in that said current-to-voltage converter by iron core, through the electrical network electric wire of core window setting as winding, and iron core on the secondary winding that is provided with constitute as output.
3, motor protecting switch according to claim 1 and 2; it is characterized in that said voltage stabilizing circuit unit is made of following structure: comprise two rectifier bridges that are electrically connected on two-way current-to-voltage converter secondary winding respectively, two rectification bridge output ends are in parallel and be electrically connected with the direct current regulation circuit and the output thereof that are made of resistance, voltage-stabiliser tube, electric capacity and be electrically connected with the secondary integrated package of pressure-stabilizing.
4, according to claim 1 or 2 or 3 described motor protecting switch; it is characterized in that said each signal sample circuit is made of following structure; have and be electrically connected on the current-to-voltage converter secondary winding and utilize two brachium pontis of voltage stabilizing circuit rectifier bridge and the signal sampling rectifier bridge that forms, this electric bridge output electrically connects as it through voltage divider and comparison circuit signal input part sampled signal is provided.
5,, it is characterized in that said delay anti-jamming circuit unit is made of following structure: have triode (T according to the described motor protecting switch of claim 1
2), its emitter grounding, its base stage is connected to voltage-stabiliser tube (DW
2) and through resistance (R
21) being electrically connected on the output of a direct current regulation circuit of voltage-stabilized power supply circuit unit, its collector electrode is connected to electric capacity (C over the ground
5); Have photoelectrical coupler, luminous tube one end (pin 1) the AND circuit output end of this coupler is electrically connected, and holds (pin 2) ground connection in addition, and photosensitive tube one end (pin 4) of this coupler is through resistance (R
21) connecing the output of a direct current regulation circuit, end (pin 3) meets triode (T in addition
2) collector electrode, triode (T
2) collector electrode is through voltage-stabiliser tube (DW
3) be electrically connected with the power amplifier input.
6,, it is characterized in that said circuit breaker trip power supply can be connected to three-plase half wave rectifier circuit and be constituted by four diodes, wherein by a lead in the three phase network, just advance to bear out diode (D according to the described motor protecting switch of claim 1
15), bear and into just going out diode (D
16), bear and into just going out diode (D
17), just advance to bear out diode (D
18), be electrically connected successively to the 3rd electrical network electric wire; By diode (D
15) and (D
16) between tap be electrically connected with a feeder ear of controllable silicon (SCR); By diode (D
16) and (D
17) between tap be electrically connected with second electrical network electric wire; By diode (D
17) and (D
18) between tap be electrically connected through the output of circuit breaker shunt opening trip coil with controllable silicon (SCR).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 98208653 CN2385458Y (en) | 1998-03-27 | 1998-03-27 | Protective switch for electric machine |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 98208653 CN2385458Y (en) | 1998-03-27 | 1998-03-27 | Protective switch for electric machine |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN2385458Y true CN2385458Y (en) | 2000-06-28 |
Family
ID=33964305
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 98208653 Expired - Fee Related CN2385458Y (en) | 1998-03-27 | 1998-03-27 | Protective switch for electric machine |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN2385458Y (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104377653A (en) * | 2014-11-10 | 2015-02-25 | 国家电网公司 | Motor protection controller |
| CN109712834A (en) * | 2019-02-19 | 2019-05-03 | 中国人民解放军海军工程大学 | A kind of high performance electrical engineering distributor breaker |
-
1998
- 1998-03-27 CN CN 98208653 patent/CN2385458Y/en not_active Expired - Fee Related
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104377653A (en) * | 2014-11-10 | 2015-02-25 | 国家电网公司 | Motor protection controller |
| CN104377653B (en) * | 2014-11-10 | 2017-11-10 | 国家电网公司 | motor protection controller |
| CN109712834A (en) * | 2019-02-19 | 2019-05-03 | 中国人民解放军海军工程大学 | A kind of high performance electrical engineering distributor breaker |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| 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 |