CN203339670U

CN203339670U - Three-phase star type motor open-phase protector

Info

Publication number: CN203339670U
Application number: CN2013202327057U
Authority: CN
Inventors: 刘万良
Original assignee: Individual
Current assignee: Individual
Priority date: 2013-05-03
Filing date: 2013-05-03
Publication date: 2013-12-11
Anticipated expiration: 2023-05-03

Abstract

A three-phase star type motor open-phase protector comprises a direct current source circuit, a detection circuit and an execution circuit. The detection circuit is composed of three optoelectronic couplers ICa, ICb, ICc, an and gate IC2, a NOR gate IC1, a NOT gate IC3, an NAND gate IC4 and two triodes VT1, VT2 for amplification. The input ends of the three optoelectronic couplers are respectively connected with one of the three input end phases (phase A, phase B and phase C) of a three-phase power supply of a motor and further respectively connected with a neutral line contact Y of the three-phase power supply. Three-phase windings of the motor are connected in a star type way. The output ends of the three optoelectronic couplers are respectively connected with the three input ends of the NOR gate IC1. The output end of the NOR gate IC1 is connected with the base electrode of one triode VT1 in an amplification circuit sequentially through the NOT gate IC3, the NAND gate IC4, an isolation diode VD1 and a resistor R3. Meanwhile, the output end of the NOR gate IC1 is further respectively connected with the three input ends of the and gate IC2. The output end of the and gate IC2 is directly connected with the base electrode of the other triode VT2 in the amplification circuit after passing through NOT gates IC4b, IC3b. After the collector electrode output ends of the triodes VT1, VT2 are connected in a parallel way, the collector electrode output ends of the triodes VT1, VT2 are further connected with the input end of the execution circuit. The three-phase star type motor open-phase protector has the characteristics of great reaction speed and flexible motion and can make a three-phase star type motor work in a stable and reliable way.

Description

The star-like motor phase failure protection device of three-phase

Technical field

The utility model relates to a kind of power protector, is the star-like motor phase failure protection device of a kind of three-phase specifically.

Background technology

As everyone knows, the motor that some power are larger, be all generally with the star-like motor of three-phase.Yet this motor, due to the reason of itself or exterior line power supply often make one in three phase mains mutually or two-phase voltage undesired, even outage, cause " phase shortage " phenomenon, this motor used under non-full-phase state, can cause in a short time load to descend, slow down, the time slightly length will burn out motor because of heating, even cause fire incident.

Summary of the invention

For overcoming the existing star-like motor of three-phase; normal the problems referred to above that occur in use procedure; the utility model provides a kind of three-phase star-like motor phase failure protection device, in order to stablize the work of threephase motor, prevents to burn out motor or the accident of breaking out of fire even.

For solving its technical problem; the technical solution adopted in the utility model is: in the input power loop of the star-like motor of three-phase; be in series with a pair of relay normally closed contact that controlled by this circuit brake; when because of motor self or outside line reason, power supply " phase shortage " occurring; the work of circuit brake demand working relay; normally closed contact is opened a way immediately, cuts off the input power of motor, reaches the purpose of protection motor.Its feature is: 1. the star-like motor phase failure protection device of described three-phase, it comprises: DC power supply circuit, testing circuit and executive circuit, described testing circuit is by three photoelectrical coupler ICa, ICb, ICc, with door IC ₂, NOR gate IC1, not gate IC3, NAND gate IC4, two the triode VT1, the VT2 that play amplifications form, wherein the input of three photoelectrical coupler ICa, ICb, ICc is connected with the neutral line contact Y of three input A, B, C phase and the three phase mains of motor three phase mains respectively, the star-like connection of three phase windings of motor; The output of three photoelectrical coupler ICa, ICb, ICc respectively with NOR gate IC ₁three inputs be connected, the output of this NOR gate IC1 is through not gate IC _3,nAND gate IC ₄after by being connected with the base stage of a triode VT1 of amplifying circuit after isolating diode VD1 and resistance R 3; Simultaneously the output of three photoelectrical coupler ICa, ICb, ICc also is connected respectively with three inputs of door IC2, should after two not gate IC4b, IC3b, directly with the base stage of another triode VT2 of amplifying circuit, be connected with the output of door IC2, after the collector output parallel connection of two amplifying triode VT1, VT2, with the input of executive circuit, be connected; Described DC power supply circuit is comprised of rectification, voltage stabilizing and filter circuit, the AC 220 V voltage of input is become to 12 volts of Voltage-outputs of direct current, for this protector self;

2.described executive circuit, the relay K be connected in series in driving triode VT3 and this triode VT3 collector electrode forms, and drives the base input end of triode VT3 to be serially connected with isolating diode VD3, shunt capacitance C2, current-limiting resistance R4; One end of relay K is connected with triode VT3 collector electrode, and the other end is connected with 12 volts of direct voltages of DC power supply circuit output, is parallel with the indicating circuit that diode VD2 and LED and current-limiting resistance R5 form at the relay K two ends.

Compared with prior art; the utility model has following characteristics and progress: due to the testing circuit employing photoelectrical coupler of this protector; and be three phase mains respectively with the input phase of three photoelectrical couplers; as long as there is a phase power supply undesired; connect photoelectrical coupler output will pass through executive circuit, drive the relay adhesive, disconnect normally closed contact; thereby the input power of outage motivation, reach the purpose of protecting motor.Therefore the utility model has flexible movements, reaction speed fast, the reliable advantage of working stability.

The accompanying drawing explanation

Fig. 1 is circuit theory diagrams of the present utility model.

In figure: 1, A, B, C are three contacts of motor three phase mains, the Y point that Y is motor;

2, T is transformer, and ZL is rectifier, and W is 12 volts of stabilizers;

3, ICa, ICb, ICc are three photoelectrical couplers;

4, IC ₁nOR gate, IC ₃not gate, IC ₄nAND gate, IC ₂with door;

5, VT1, VT2 are respectively two amplifying triodes, and VT3 drives triode;

6, K is relay.

Embodiment

Below in conjunction with accompanying drawing, the utility model is further illustrated:

With reference to accompanying drawing 1: in the input power loop of the star-like motor of three-phase; be in series with a pair of relay normally closed contact KJ-KD that controlled by this circuit brake; when because of motor self or outside line reason, power supply " phase shortage " occurring; the work of circuit brake demand working relay; normally closed contact is opened a way immediately; cut off the input power of motor, reach the purpose of protection motor.Described circuit brake comprises following circuit: DC power supply circuit, testing circuit and executive circuit, wherein DC power electric routing transformer T, rectifier ZL, 7812 pressurizer W and filter capacitor C0 form, the AC 220 V voltage of input is become to 12 volts of Voltage-outputs of direct current, for this protector self; Described testing circuit is by three photoelectrical coupler ICa, ICb, ICc, one with a door IC ₂three NAND gate IC1, IC3, IC4, two triode VT1, VT2 that play amplification form, wherein the input of three photoelectrical coupler ICa, ICb, ICc is connected with three input A, B, C of motor three phase mains respectively, Y presses the Y point of motor, the output of three photoelectrical coupler ICa, ICb, ICc respectively with a NAND gate IC ₁three inputs be connected, the output of this NAND gate is through IC _3,iC ₄two non-behind the door by isolation diode VD1 with after capacitor C 1 and resistance R 3, with the base stage of the triode VT1 of amplifying circuit, be connected; Simultaneously the output of three photoelectrical coupler ICa, ICb, ICc also is connected with three inputs with an IC2 respectively, should directly with the base stage of another triode VT2 of amplifying circuit, be connected after two not gate IC4b, IC3b with the output of door, after the collector output parallel connection of two amplifying triode VT1, VT2, be connected with the input of executive circuit by isolating diode VD3 and capacitor C2.

Described executive circuit, the relay K be connected in series in driving triode VT3 and this triode VT3 collector electrode forms, and drives the base input end of triode VT3 to be serially connected with isolating diode VD3, shunt capacitance C2, current-limiting resistance R4; One end of relay K is connected with triode VT3 collector electrode, and the other end is connected with 12 volts of direct voltages of DC power supply circuit output, is parallel with the indicating circuit that diode VD2 and LED and current-limiting resistance R5 form at the relay K two ends.

During work, work as power supply opening, protector is obtained the 15V AC power through transformer T, and through rectifier ZL, pressurizer W, after filter capacitor CO, to provide+12V of late-class circuit DC power supply; At this moment motor not yet starts; protector is started working; because of all not energisings of A, B, C three-phase; be connected in parallel on A, B, C and the equal non-transformer of Y point on motor; be photoelectrical coupler ICa, ICb, all not conductings of ICc; at this moment three inputs of NOR gate IC1 all are low level; output is high level; after not gate IC3a oppositely exports, it is low level; be output as high level through NAND gate IC4a again, at this moment triode VT1 conducting, triode VT1 conducting triode VT3 can not conducting; because capacitor C 2 is larger than capacitor C 1 capacity, relay K is failure to actuate.Be low level with door IC2 because of input, output is low level, and NAND gate IC4b is output as high level, after not gate IC3b oppositely exports, is low level, at this moment not conducting of triode VT2 simultaneously;

After actuating motor, the A, B, C to the Y point that are connected in parallel on motor all have electric current, photoelectrical coupler ICa, ICb, the equal conducting of ICc, NOR gate IC1 is output as low level, oppositely be output as high level through not gate IC3a, be output as low level through NAND gate IC4a again, but because the voltage at capacitor C 1 two ends can not suddenly change, so still safeguard triode VT1 conducting.Meanwhile with door IC2 input, all be high level, output is also high level, and at this moment two of NAND gate IC4b inputs all are high level, the low level of exporting, after not gate IC3b output, be high level, triode VT2 conducting, triode VT2 conducting triode VT3 can not conducting;

When A, B, any phase phase shortage no current of C three-phase; with door IC2 output be low level; at this moment NAND gate IC4b is output as high level; after not gate IC3b oppositely exports, be low level, triode VT2 closes, triode VT3 conducting simultaneously; the relay K action; normally-closed contact KJ, the KD of the relay K of string in electromotor control circuit disconnects, the cutting-off controlling power supply, thus reach protective effect.

Claims

1. the star-like motor phase failure protection device of three-phase, it comprises: DC power supply circuit, testing circuit and executive circuit is characterized in that: described testing circuit is by three photoelectrical coupler ICa, ICb, ICc, with door IC ₂, NOR gate IC1, not gate IC3, NAND gate IC4, two the triode VT1, the VT2 that play amplifications form, wherein the input of three photoelectrical coupler ICa, ICb, ICc is connected with the neutral line contact Y of three input A, B, C phase and the three phase mains of motor three phase mains respectively, the star-like connection of three phase windings of motor; The output of three photoelectrical coupler ICa, ICb, ICc respectively with NOR gate IC ₁three inputs be connected, the output of this NOR gate IC1 is through not gate IC _3,nAND gate IC ₄after by being connected with the base stage of a triode VT1 of amplifying circuit after isolating diode VD1 and resistance R 3; Simultaneously the output of three photoelectrical coupler ICa, ICb, ICc also is connected respectively with three inputs of door IC2, should after two not gate IC4b, IC3b, directly with the base stage of another triode VT2 of amplifying circuit, be connected with the output of door IC2, after the collector output parallel connection of two amplifying triode VT1, VT2, with the input of executive circuit, be connected; Described DC power supply circuit is comprised of rectification, voltage stabilizing and filter circuit, the AC 220 V voltage of input is become to 12 volts of Voltage-outputs of direct current, for this protector self.

2. the star-like motor phase failure protection device of three-phase according to claim 1, it is characterized in that: described executive circuit, the relay K be connected in series in driving triode VT3 and this triode VT3 collector electrode forms, and drives the base input end of triode VT3 to be serially connected with isolating diode VD3, shunt capacitance C2, current-limiting resistance R4; One end of relay K is connected with triode VT3 collector electrode, and the other end is connected with 12 volts of direct voltages of DC power supply circuit output, is parallel with the indicating circuit that diode VD2 and LED and current-limiting resistance R5 form at the relay K two ends.