CN2261681Y

CN2261681Y - Phase-loss protector for ac motor with optical coupling isolating air switch

Info

Publication number: CN2261681Y
Application number: CN 96228601
Authority: CN
Inventors: 马承柱
Original assignee: Individual
Current assignee: Individual
Priority date: 1996-08-19
Filing date: 1996-08-19
Publication date: 1997-09-03
Anticipated expiration: 2006-08-19

Abstract

The utility model discloses an opto-coupler isolation air switch execution type alternating current motor protector, it sets up in the power input end of motor to lack looks signal sampling point, through bridge rectifier circuit, filter circuit, optoelectronic coupling circuit, the phase inverter, the control circuit that voltage comparator and impulse circuit connected gradually, and adopt 337 or 333 series air switch for executive component, it is strong to have stability, the commonality is good, sensitivity is high, the interference killing feature that also can effectual realization lack the looks protection when especially causing to lack looks as executive component's contact glues to die.

Description

Light-coupled isolation air switch execution type alternating current motor open phase protector

The utility model relates to a kind of motor protecting device, is specially a kind of light-coupled isolation air switch execution type alternating current motor open phase protector.

At present, producing in the society and use in the alternating current motor phase-lacking protective device many kinds are arranged, as application number is that 87210832 patent application discloses a kind of name and is called energy-conservation threephase motor phase shortage Automatic Protection Switching, it is made up of phase shortage automatic safety device and Three-phase knife switch, electromagnetic coil circuit no power when motor runs well of its one group of control Three-phase knife switch, only lacking a certain phase time in idol just switches on, make electromagnetic attraction draw back knife switch, thereby realize the task of open-phase protection; Application number is that 92237350 patent application discloses a kind of name and is called the inclined to one side phase open phase protector of light stream motor for another example, and this protector belongs to the emergency protective circuit device, is used for making electronic function break away from electrical network automatically when the inclined to one side phase phase shortage of electrical network.Though existing all kinds of alternating current motor phase-lacking protective device can be realized the task of open-phase protection under certain condition; stability is low, versatility is poor, sensitivity is low, poor anti jamming capability but really have, and particularly has the defective that motor open phase time that cause can't be protected when the contact of executive component is extremely sticking.

Task of the present utility model is to provide that a kind of stability is strong, versatility good, highly sensitive, antijamming capability is strong, particularly when the contact of executive component sticking dead and motor open phase time that cause also can effectively be realized the novel light-coupled isolation air switch execution type alternating current motor open phase protector of open-phase protection.

Task of the present utility model takes following scheme to realize.

Accompanying drawing 1 and accompanying drawing 2 have provided electrical block diagram of the present utility model.

In the accompanying drawings, NABC is that three-phase alternating-current supply, U1 are bridge rectifier, V1 For crystal diode, V2, V3, V4 adopt model be 3DG series transistor, V5 employing model is that photoelectrical coupler, the IC employing model of 4N35 is LM158's Operational amplifier integrated circuit, XY are that silence switch, KA1 employing model are HG412 3 relay, KA1-2 are that normally-closed contact, the B1 of relay K A1 is electric bell, Q F employing model is that air switch, the RJ of DZ10/337 series is electrothermal relay, RJ-1 For the normally-closed contact of electrothermal relay, actuating coil, the KM1-4 that KM is A.C. contactor are Four groups of normally opened contacts of A.C. contactor, QF-1 be air switch QF three groups of normally opened contacts, K, TA, QA be switch, RP1 be adjustable resistor, R1-R13 be resistor, C1-C3 is that capacitor, M are motor.

Below will be described as follows concrete structure of the present utility model with reference to the accompanying drawings:

With reference to the accompanying drawings, ABC phase line among the three-phase four-wire system AC power cord N.A.B.C is respectively by being connected with the end of three groups of normally opened contact KM1-3 of A.C. contactor KM behind three groups of normally opened contacts of air switch QF, the other end of KM1-3 is connected with motor M after by thermal relay RJ, the A.B.C phase line power supply contact A0 of motor M, B0, C0 is respectively by being connected with the input of bridge rectifier U1 behind the resistor R 1.R2.R3 and being connected with the other end short circuit of zero line N and bridge rectifier U1 by resistor R 4 backs, the two output cross-over connections of bridge rectifier U1 are by resistor R 5, R6 and capacitor C1, the filter circuit that C2 forms, cross-over connection has adjustable resistor RP1 between two outputs of filter circuit, the sliding end of RP1 is that the 1st pin is connected with the 2nd pin with two inputs of photoelectrical coupler V5 respectively with a stiff end, the 4th pin of V5 is connected with common port, its output the 5th pin is connected with the positive pole of diode V1 and is connected with power Vcc and by being connected with common port behind the capacitor C3 by resistor R 7 back, the negative pole of diode V1 is connected with the base stage of triode V2, the emitter of V2 is connected with common port, its collector electrode is connected with the negative pole end of light-emitting diode L1, the positive pole of L1 is connected with power Vcc by resistor R 8 backs, the collector electrode of V2 is connected with positive input terminal the 3rd pin of operational amplifier Ic by resistor R 9 backs, negative input end the 2nd pin of Ic is connected with common port by resistor R 11 backs and is connected with power Vcc by resistor R 10 backs, output the 1st pin of Ic is connected with the ground level of triode V3 by resistor R 12 backs, the emitter of V3 is connected with the base stage of triode V4, the emitter of V4 is connected with common port, the collector electrode of V4 is connected with Vcc after by the actuating coil of relay K A1, after joining, the collector electrode short circuit of V3 and V4 is connected with the negative pole end of light-emitting diode L2, the positive pole of L2 is connected with power Vcc by resistor R 13 backs, silence switch XY, the normally opened contact KA1-1 of relay K A1, be connected across between power Vcc and the common port after the electric bell B1 serial connection, be connected in series K switch successively mutually and between the C phase line at three phase mains B, the normally-closed contact KA1-2 of relay K A1, the actuating coil of air switch QF, between three phase mains zero line N and A phase line, be connected in series switch TA successively, QA, the actuating coil of A.C. contactor KM, the normally opened contact RJ-1 of thermal relay RJ, and meet the normally opened contact KM-4 of A.C. contactor KM at two end spaies of switch QA.

Below with reference to accompanying drawing the course of work of the present utility model is described as follows:

With reference to the accompanying drawings; during work; three-phase voltage in sending into motor M is during if any arbitrary phase voltage phase shortage; two ends of R4 will obtain the phase shortage ac voltage signal in the phase shortage sample circuit that is made of resistor R 1-R3 and R4; this signal through bridge rectifier and filter circuit rectifying and wave-filtering after photoelectrical coupler V5 sends into the base stage of inverter transistor V2; the in-phase input end that signal after V2 is anti-phase is sent into the voltage comparator of being made up of IC makes its output output high level; this high level signal makes the promotion circuit turn-on of being made up of triode V3 and V4 promote relay K A1 conducting; the normally opened contact KA1-1 closure of relay K A1; electric bell B1 must conduct; send the phase shortage alarm signal; its normally-closed contact KA1-2 discharges the current supply circuit that cuts off air switch QF actuating coil simultaneously; its three groups of normally-closed contact QF-1 are disconnected, thereby realize cutting off the task that main circuit power is realized the protection motor.

The utility model has following evident characteristic, and (1) owing to adopt 337 or 333 serial air switches as executive component, having overcome the employing contactor is the often sticking defective that extremely causes phase shortage in its contact of executive component; (2) owing to adopted the optocoupler separating technology, make its front and back level realize effective isolation, avoided making back level control element to exempt from the impact and the interference of forceful electric power signal, improved the reliability of circuit, increased antijamming capability; (3) because the default phase signal sampled point is arranged at the power input of motor, so, all can realize effective protection so long as input to when the power supply of motor has a phase shortage no matter be the phase shortage that when causes; (4) the utility model is adapted to the open-phase protection of the motor of all kinds of different models, therefore has the good feature of versatility.

Can effectively realize task of the present utility model in sum; for society provide that a kind of stability is strong, versatility good, highly sensitive, antijamming capability is strong, particularly when the contact of executive component sticking dead and cause the motor open phase time also can effectively realize the novel light-coupled isolation air switch execution type alternating current motor open phase protector of open-phase protection.

Claims

1; a kind of light-coupled isolation air switch execution type alternating current machine open phase protector; comprise bridge rectifier U1; crystal diode V1; transistor V2; V3; V4; photoelectrical coupler V5; operational amplifier integrated circuit Ic; silence switch XY; relay K A1; electric bell B1; air switch QF; thermal relay RJ; K switch; TA; QA; resistor R 1-R13; adjustable resistor RP1; capacitor C1-C3; it is characterized in that: the ABC phase line among the three-phase four-wire system AC power cord N.A.B.C is respectively by being connected with the end of three groups of normally opened contact KM1-3 of A.C. contactor KM behind three groups of normally opened contacts of air switch QF; the other end of KM1-3 is connected with motor M by thermal relay RJ; the A.B.C phase line power supply contact A0 of motor M; B0; C0 is respectively by being connected with the input of bridge rectifier U1 behind the resistor R 1.R2.R3 and being connected with the other end short circuit of zero line N and bridge rectifier U1 by resistor R 4 backs; the two output cross-over connections of bridge rectifier U1 are by resistor R 5; R6 and capacitor C1; the filter circuit that C2 forms; cross-over connection has adjustable resistor RP1 between two outputs of filter circuit; the sliding end of RP1 is that the 1st pin is connected with the 2nd pin with two inputs of photoelectrical coupler V5 respectively with a stiff end; the 4th pin of V5 is connected with common port; its output the 5th pin is connected with the positive pole of diode V1 and is connected with power Vcc and by being connected with common port behind the capacitor C3 by resistor R 7 back; the negative pole of diode V1 is connected with the base stage of triode V2; the emitter of V2 is connected with common port; its collector electrode is connected with the negative pole end of light-emitting diode L1; the positive pole of L1 is connected with power Vcc by resistor R 8 backs; the collector electrode of v2 is connected with positive input terminal the 3rd pin of operational amplifier Ic by resistor R 9 backs; negative input end the 2nd pin of Ic is connected with common port by resistor R 11 backs and is connected with power Vcc by resistor R 10 backs; output the 1st pin of Ic is connected with the ground level of triode V3 by resistor R 12 backs; the emitter of V3 is connected with the base stage of triode V4; the emitter of V4 is connected with common port; the collector electrode of V4 is connected with Vcc after by the actuating coil of relay K A1; after joining, the collector electrode short circuit of V3 and V4 is connected with the negative pole end of light-emitting diode L2; the positive pole of L2 is connected with power Vcc by resistor R 13 backs; silence switch XY; the normally opened contact KA1-1 of relay K A1; be connected across between power Vcc and the common port after the electric bell B1 serial connection; be connected in series K switch successively mutually and between the C phase line at three phase mains B; the normally-closed contact KA1-2 of relay K A1; the actuating coil of air switch QF; between three phase mains zero line N and A phase line, be connected in series switch TA successively; QA; the actuating coil of A.C. contactor KM; the normally opened contact RJ-1 of thermal relay RJ, and meet the normally opened contact KM-4 of A.C. contactor KM at two end spaies of switch QA.