CN1074560A - Control disconnected and power-supply circuit and application thereof - Google Patents

Abstract

A kind of control disconnected and power-supply circuit and application thereof are disclosed.Control disconnected with power-supply circuit in have be series at ac contactor coil on the rectification circuit that links to each other of external terminal, behind the rectification circuit controlling circuit of voltage regulation, relay, the amplifier that relay is subjected to join with external control signal is controlled, and controlling circuit of voltage regulation output is external.Used in the protector of foregoing circuit current transformer has been arranged; three groups are amplified and rectification circuit connects current transformer; amplification and rectification circuit connect signal comparator circuit, and signal comparator circuit connects the disconnected and power-supply circuit of control through a pulse shaping circuit, and control is disconnected to provide power supply with power-supply circuit for foregoing circuit.

Description

Control disconnected and power-supply circuit and application thereof

The present invention relates to the emergency protective circuit device in generating, power transformation or the distribution technique of electric power, is a kind of automatic disconnection emergency protective circuit device that the undesirable variation that departs from the normal electrical working condition is directly reacted.Also relating to electric switch, relay in the essential electronic element, is a kind of circuit arrangement of electric switch; In other words conj.or perhaps a kind of non-relay special-purpose that is applicable to, the circuit arrangement that is used to obtain required operating characteristic or exciting curent is provided, specifically, be a kind of be used for improving relay-operated, produce the circuit arrangement of relay deferred action.

Existing timing (time-delay), program control, and failure protecting device in all need to be provided with the power supply of the voltage stabilizing circuit of band transformer and complexity in the circuit of the actions such as control break-make adopted; but also need externally being set, special-purpose circuit links to each other with power supply; consumed power not only; the volume and the installation difficulty of device have been increased; but also need according to different voltage occasions, design such as different electric plant capacity with select different circuit structure schemes, the circuit complexity; bad adaptability, cost are also higher.But also there is the integrity problem of work.

The purpose of this invention is to provide that a kind of volume is little, cost is low, adaptability is good, control disconnected and the power-supply circuit and the application thereof of stable performance, reliable operation.

Technical solution of the present invention is:

Disconnected and the power-supply circuit of a kind of control has and the diverse design of prior art; A rectification circuit that joins with two terminals that are series on the external communication contactor coil is arranged, be connected to controlling circuit of voltage regulation behind the rectification circuit, relay and controlling circuit of voltage regulation join, relay is controlled by an amplifier that joins with external control signal generation circuit, a normally-closed contact of relay is connected in the controlling circuit of voltage regulation, and controlling circuit of voltage regulation output is also external by output contact.

Comprise a controllable silicon in the controlling circuit of voltage regulation among the present invention, the silicon controlled control utmost point is connected to a triode, and triode is subjected to the control of a voltage-stabiliser tube, and the normally-closed contact of relay is between controllable silicon and triode.Certainly, controlling circuit of voltage regulation also can adopt other suitable circuit structure forms.

A kind of general protector of threephase asynchronous machine of having used the disconnected and power-supply circuit of aforementioned control; comprise the threephase current transformer that is used to sample; the difference of itself and prior art is: have three groups to amplify and rectification circuit is accepted the signal that threephase current transformer is sent respectively; amplification and rectification circuit are delivered to signal comparator circuit with signal; the signal comparator circuit output signal is through the disconnected and power-supply circuit of pulse shaping circuit control control, and control is broken and power-supply circuit provides required power supply for remaining circuit.

Signal comparator circuit among the present invention comprises overload signal comparator and phase failure signal comparator.Certainly, but also wherein a kind of signal comparator or also comprise other signal comparators.

Phase failure signal comparator output among the present invention is connected to anti-jamming circuit.Overload signal comparator output signal and a starting current dodge circuit output signal with after connect pulse shaping circuit.Certainly, also available other the suitable circuit structure forms of foregoing circuit version substitute.

Amplification among the present invention and rectification circuit comprise the amplifying circuit that joins with current transformer, and are connected on the rectification circuit after the amplifying circuit.Certainly, amplification and rectification circuit also can adopt other suitable circuit structure forms.

Starting current among the present invention is dodged and is comprised a voltage comparator in the circuit, an input of voltage comparator is connected to a RC charge circuit and diode discharge loop, and another input of voltage comparator is connected to a voltage stabilizing circuit that the comparator voltage benchmark is provided.Certainly, also can adopt other suitable circuit structure forms.

Advantage of the present invention is: volume is little, circuit structure is simple; stable performance, applied widely, can be used for regularly (time-delay), program control, reach in the various fault secure circuit devices, easy to install; no matter the watt level that voltage swing, electrical equipment are provided with is all applicable.Compared with prior art, do not need to establish special power circuit in addition, external cabling is few, and power consumption is little.Have high reliability and high anti-jamming capacity.

Below in conjunction with drawings and Examples the present invention is described in further detail:

Fig. 1 is the disconnected and power-supply circuit structural representation of a kind of control of the present invention.

Fig. 2 is for using the general protector schematic block circuit diagram of threephase asynchronous machine of the disconnected and power-supply circuit of control of the present invention.

Fig. 3 is the general protector electrical schematic diagram of threephase asynchronous machine of the disconnected and power-supply circuit of the control of application drawing 1.

Fig. 1 has described the disconnected and power-supply circuit of a kind of control of the present invention.Diode D1, D2, D3, D4 have formed a bridge rectifier.Contact A, B are used for being series in the sucking coil loop of A.C. contactor of break-makes such as outside electrical equipment of control or circuit.In the moment of A.C. contactor adhesive, capacitor C1 goes up no electric charge.Contact A, B are short-circuit condition between two ends, the smooth adhesive of A.C. contactor, after the adhesive, the voltage that fills necessarily on the capacitor C1 is when this voltage surpasses the voltage stabilizing threshold values of voltage stabilizing didoe W1, triode BG1 conducting, then controllable silicon TD conducting stops for the charging of capacitor C1, when the second half of alternating current arrives, repeat said process, thereby have a galvanic current to press on the capacitor C1.When external control signal makes the relay J adhesive, the normally-closed contact JK open circuit of relay J, and because the characteristic that the zero passage of controllable silicon TD disconnects, contact JK will not produce spark when disconnecting, therefore the volume of relay J can be less than the relay of available technology adopting, and useful life is longer.Piezo-resistance RY is used to protect controllable silicon TD.Also comprise diode D5 in the circuit, resistance R 1 etc.Because above-mentioned control is disconnected and the effect of power-supply circuit, after the A.C. contactor adhesive, the supply power voltage of the voltage ratio reality of keeping adhesive of ac contactor coil is wanted several volts on the low side, because the pick-up voltage of A.C. contactor suitably reduces the life-span of coil much larger than release voltage.This shows; disconnected and the power-supply circuit of this control has produced the A.C. contactor desirable pressure drop of lengthening the life; and this pressure drop offers thereafter protector, (time-delay) device regularly; circuit such as controller; entire circuit is therefore much simple, small and exquisite than power supply circuits used in the prior art; and saved outside supply line, and do not consume extra electric energy yet, also can be applicable to different operating voltage environment.

Fig. 2 has described the operation principle of using the general protector of threephase asynchronous machine of controlling disconnected and power-supply circuit.Terminals A, B are its two unique external terminals, and it both had been responsible for the sucking coil of the A.C. contactor of automatic disconnection control motor break-make when breaking down, and was used for again providing the whole protecting device required electric energy when motor moves.Three current transformers are wearing the triple line of motor respectively, what link to each other respectively with three current transformers is that three stageds are amplified and rectification circuit, three stageds are amplified and rectification circuit connects phase failure signal comparator through a simulation AND gate, connect pulse shaping circuit through anti-jamming circuit again, pulse shaping circuit connects the disconnected and power-supply circuit of control.Three stageds are amplified and rectification circuit also connects an overload signal comparator through a simulation OR-gate, and the output signal that its output signal and starting current are dodged circuit is delivered to pulse shaping circuit through an AND gate.

The operation principle of entire circuit is: behind motor start-up; protector must be established beginning work by cable; when motor also is in starting state; because starting current is dodged the effect of circuit; overload protection wouldn't be worked; open-phase protection circuit is then started working; the three-phase current of motor detects through three current transformers and gives staged amplification and rectification circuit; three tunnel outputs through simulation " with " send phase failure signal comparator; when open phase fault takes place; simulation AND output level is minimum; phase failure signal comparator has output, and arrives pulse shaping circuit through anti-interference loop, makes then to control the disconnected open circuit shape that becomes with power-supply circuit; A.C. contactor moves subsequently, and the motor outage is protected.If there is not open phase fault to take place; phase failure comparator no-output then, three road signals that amplify rectification output through simulation " or " send the overload signal comparator, when overload takes place when; this overload signal comparator has output, also realizes the power-off protection of motor through pulse shaping circuit.

Fig. 3 has described the example of the general protector of threephase asynchronous machine of using the disconnected and power-supply circuit of control of the present invention.By diode D1, D2, D3, D4, D5, W1, controllable silicon TD, triode BG1, BG2, relay J, resistance R 1, RY, capacitor C 1 grade has been formed the disconnected and power-supply circuit of control, three current transformer L1, L2, L3 is used for detecting fault current, respectively by integrated circuit (IC) 5, IC6, IC7 and subsidiary component have been formed three staged amplifiers, form by integrated circuit (IC) 4 and subsidiary component and to resolve the phase signals comparator, formed the overload signal comparator by integrated circuit (IC) 3 and subsidiary component, formed pulse shaping circuit by integrated circuit (IC) 2 and subsidiary component, formed starting current by integrated circuit (IC) 1 and subsidiary component and dodged circuit.Other elements in the circuit comprise: resistance R 2, R3, R4, R5, R6, R7, R8, R9, R10, R11, R12, R13, R14, R15, R16, R17, R18, R19, R20, R21, R22, R23, R24, R25, R26, R27, R28, R29, capacitor C 2, C3, C4, C5, C6, C7, C8, C9, C41, diode D6, D7, D8, D9, D10, D11, D12, D13, D14, D15, D16, D17, D18, D19, D20, D21, D22, W2, W3, W4, W5, W6, W7 etc.Integrated circuit (IC) 1-IC7 adopts two four high guaily units (MC324), certainly, also can replace the integrated circuit component of other suitable types.

Because the power-supply circuit in the protector of the present invention is series in the ac contactor coil loop; its power supply have or not whether the operation with motor is synchronous; therefore adopted and be different from the forming and trigger the circuit of delaying time of prior art fully by power supply; realized dodging automatically the purpose of starting current, made not only sensitivity but also reliable of overload protection function.In order to reduce the volume of current transformer, reduce cost, the current detection circuit of this example has adopted the first circuit arrangement that amplifies the back rectification.In order to make the present invention all have reliable phase failure protection function equally to the motor of different capacity, current signal amplifier circuit has adopted the staged amplifying circuit, and the overload protection sensitivity also has very wide adjusting range.

When using the protector of this example, the three-phase power line that only needs to connect motor passes from three detection holes (current transformer) of protector, and the arbitrary position that then two lead-in wires is series at the ac contactor coil loop gets final product.For sensitivity and the reliability that guarantees overload protection, elder generation transfers resistance R 8 to make sensitivity minimum, and starter motor till possible peak load state downward modulation economize on electricity resistance R8 arrives the protection action, is oppositely finely tuned a little then then.

Claims (8)

1, the disconnected and power-supply circuit of a kind of control, it is characterized in that: a rectification circuit that joins with two terminals that are series on the external communication contactor coil is arranged, be connected to controlling circuit of voltage regulation behind the rectification circuit, relay and controlling circuit of voltage regulation join, relay is controlled by an amplifier that joins with external control signal generation circuit, a normally-closed contact of relay is connected in the controlling circuit of voltage regulation, and controlling circuit of voltage regulation output is external by output contact.

2, the disconnected and power-supply circuit of control according to claim 1, it is characterized in that: comprise a controllable silicon in the controlling circuit of voltage regulation, the silicon controlled control utmost point is connected to a triode, and triode is subjected to the control of a voltage-stabiliser tube, and the normally-closed contact of relay is between controllable silicon and triode.

3, a kind of application rights requires the general protector of threephase asynchronous machine of the disconnected and power-supply circuit of 1 described control; comprise the threephase current transformer that is used to sample; it is characterized in that: have three groups of amplifications and rectification circuit to accept the signal that threephase current transformer is sent respectively; amplification and rectification circuit are delivered to signal comparator circuit with signal; the signal comparator circuit output signal is through the disconnected and power-supply circuit of pulse shaping circuit control control, and control is broken and power-supply circuit provides required power supply for remaining circuit.

4, the general protector of threephase asynchronous machine according to claim 3 is characterized in that: signal comparator circuit comprises overload signal comparator and phase failure signal comparator.

5, the general protector of threephase asynchronous machine according to claim 4 is characterized in that: phase failure signal comparator output is connected to anti-jamming circuit.

6, the general protector of threephase asynchronous machine according to claim 4 is characterized in that: overload signal comparator output signal and a starting current dodge circuit output signal mutually " with " after connect pulse shaping circuit.

7, according to claim 3 or 4,5, the general protector of 6 described threephase asynchronous machines, it is characterized in that: amplification and rectification circuit comprise the amplifying circuit that joins with current transformer, and are connected on the rectification circuit after the amplifying circuit.

8, the general protector of threephase asynchronous machine according to claim 6; it is characterized in that: starting current is dodged and is comprised a voltage comparator in the circuit; an input of voltage comparator is connected to a RC charge circuit and diode discharge loop, and another input of voltage comparator is connected to a voltage stabilizing circuit that the comparator voltage benchmark is provided.

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