CN201699389U

CN201699389U - Pulsating direct-current electricity-leakage and overvoltage protection device for electricity-leakage protection switch

Info

Publication number: CN201699389U
Application number: CN2010202357415U
Authority: CN
Inventors: 王赵
Original assignee: Individual
Current assignee: Individual
Priority date: 2010-06-24
Filing date: 2010-06-24
Publication date: 2011-01-05
Anticipated expiration: 2020-06-24

Abstract

The utility model provides a pulsating direct-current electricity-leakage and overvoltage protection device for an electricity-leakage protection switch, which comprises an electricity-leakage inductor, an electricity-leakage detection circuit, a power input unit, an overvoltage detection circuit and a power switch unit, wherein the electricity-leakage inductor is used for inducting an electricity-leakage signal, converting the current signal into a voltage signal and transmitting the voltage signal to the electricity-leakage detection circuit, and the electricity-leakage detection circuit is used for inputting direct-current voltage obtained by filtering, amplifying and rectifying the received electricity-leakage signal to the power switch unit; and the power input unit is connected with the overvoltage detection circuit, and the overvoltage detection circuit is connected with the power switch unit. The switching-off of an electric power supply of a line to be protected is realized by the power switch unit, and an electric-shock accident caused by electricity leakage and a safety accident caused when working abnormally are effectively prevented.

Description

The pulsating direct current electric leakage and the over-pressure safety device that are used for earth leakage circuit-breaker

Technical field:

The utility model relates to a kind of earth leakage protective device, relates in particular to pulsating direct current electric leakage and over-pressure safety device that a kind of earth leakage circuit-breaker is used for earth leakage circuit-breaker.

Background technology:

Along with improving constantly of people's quality of life, electronics, electric equipment products have entered huge numbers of families, are also progressively strengthening for the protection person and the awareness of safety of equipment, and the requirement to protector of all kinds simultaneously also improves constantly.The present employed earth leakage circuit-breaker overwhelming majority of China is the AC type, i.e. pure sinusoid ac leakage type product, and the electronic product electric leakage comprises that not only ac leakage also comprises the pulsating direct current electric leakage, and AC type leakage switch can't play a very good protection; And because the continuous increase of electrical equipment use amount, the different time sections use amount is just variant, and voltage ripple of power network is very big, can take place also sometimes that electric wire being talked over the wire and the wrong line makes the too high situation of line voltage, causes electrical equipment to damage.

Leakage switch of the prior art uses half-wave rectifying circuit can only detect ac leakage, only just can protect when ac leakage is arranged, and not have delay function; misoperation can appear; for overvoltage protection, needing increases special-purpose overvoltage protection switch, and purchase cost is risen.American-European countries only allows to produce A type electric leakage product at present, and the leakage switch of China is more single, can not satisfy the needs of external exported product, and is totally unfavorable to the outlet of China leakage switch producer; And China also advises using A type electric leakage product in medical industry, so A type leakage switch market potential is huge.

The utility model content

The utility model purpose:

Technical problem to be solved of the present utility model is to provide a kind of earth leakage circuit-breaker with pulsating direct current earth leakage protective and over-pressure safety device at the defective that above-mentioned prior art exists, and realizes that all-wave detects, and reaches the purpose of time-delay and overvoltage protection.

Technical scheme:

The utility model is for realizing that above-mentioned utility model purpose adopts following technical scheme:

A kind of pulsating direct current electric leakage and over-pressure safety device that is used for earth leakage circuit-breaker comprises electric leakage inductor, electric-leakage detection circuit, power input unit, over-voltage detection circuit, power switch unit; The output of inductor of wherein leaking electricity is connected with the input of electric-leakage detection circuit, and the output of electric-leakage detection circuit is connected with the input of power switch unit; The output of described power input unit is connected the back and links to each other with power switch unit with over-voltage detection circuit.

Further, above-mentioned pulsating direct current electric leakage and the over-pressure safety device electric-leakage detection circuit that is used for earth leakage circuit-breaker comprises low pass filter, amplifier, full-bridge rectification filter unit, first comparator, second comparator and first output unit; Wherein the input termination leakage inductance of low pass filter is answered the output of device, and the output of low pass filter connects amplifier, full-bridge rectification filter unit, first comparator, second comparator and first output unit successively.

Further, above-mentioned pulsating direct current electric leakage and the over-pressure safety device electric-leakage detection circuit that is used for earth leakage circuit-breaker also comprises the time-delay constant-current controller, and described time-delay constant-current controller is between described first comparator and second comparator.

Further; above-mentioned pulsating direct current electric leakage and the over-pressure safety device electric-leakage detection circuit that is used for earth leakage circuit-breaker also comprises the time-delay regulon; described time-delay regulon is an external capacitor, described external capacitor one end ground connection, and the other end connects the positive input of described second comparator.

Further; above-mentioned pulsating direct current electric leakage and the over-pressure safety device electric-leakage detection circuit that is used for earth leakage circuit-breaker also comprises an external filter circuit; described external filter circuit comprises a resistance and an electric capacity; an end ground connection after described resistance and the electric capacity parallel connection, the described full-bridge rectification filter unit of another termination.

Further; above-mentioned pulsating direct current electric leakage and the over-pressure safety device over-voltage detection circuit that is used for earth leakage circuit-breaker comprises voltage sampling unit, integrator, voltage detector, delay unit and second output unit; the described power input unit of input termination of described voltage sampling unit, the output of voltage sampling unit connects integrator, voltage detector, delay unit, second output unit successively.

Further; above-mentioned pulsating direct current electric leakage and the over-pressure safety device voltage sampling unit that is used for earth leakage circuit-breaker comprises first divider resistance and second divider resistance; the described power input unit of one termination of described first divider resistance; ground connection after the other end of first divider resistance is connected with second divider resistance, described second divider resistance is in parallel with integrator.

Beneficial effect:

The utility model is by having increased full-bridge rectification filter circuit in original circuit; making the electric leakage inductor sense the all-wave signal all can be compared device and detect; and increased time-delay and overvoltage crowbar, made this product can effectively prevent electric shock accidents that causes because of electric leakage and the security incident that when non-normal working, causes.

Description of drawings:

Fig. 1 is the utility model circuit structure block diagram.

Fig. 2 is the utility model circuit connection diagram.

Specific embodiments:

Be described in further detail below in conjunction with the enforcement of accompanying drawing technical scheme:

Only carry out ac leakage and detect existing problem in order to solve in the prior art in the leakage switch earth leakage protective device; the utility model has adopted full-wave rectifying circuit that leakage current is carried out all-wave and has detected; realized detection to the electric leakage of A type; and time-delay and over-voltage protecting function have been increased; after the protection circuit leakage current reaches set point or voltage and surpasses certain value; the output high potential triggers the controllable silicon conducting; reach and allow control switch thread off, a kind of protective device of effective protection power supply is provided.

In conjunction with illustrated in figures 1 and 2, pulsating direct current electric leakage and over-pressure safety device that the utility model is used for earth leakage circuit-breaker comprise electric leakage inductor 100, electric-leakage detection circuit 200, power input unit 300, over-voltage detection circuit 400, power switch unit 500, wherein electric-leakage detection circuit 200 comprises low pass filter 201, amplifier 202, full-bridge rectification filter unit 203, comparator 204 (comprises the first comparator OP1, the second comparator OP2), time-delay regulon 205, the time-delay constant-current controller 206 and first output unit 207; Over-voltage detection circuit 400 comprises: voltage sampling unit 401, integrator 402, voltage detector 403, delay unit 404 and second output unit 405.

Under the normal condition, three-phase load electric current and Ground leakage current are in a basic balance, flow through the phasor of electric leakage inductor primary winding electric current and are about zero, and promptly the total magnetic flux that is produced in iron core by it is zero, electric leakage inductor secondary coil no-output.When taking place to get an electric shock, shock current becomes the loop by the earth, that is has produced zero-sequence current.This electric current flows back to without electric leakage inductor primary winding, has destroyed balance, so the zero sequence magnetic flux is just arranged in the iron core, makes the secondary coil output signal, and the electric leakage inductor will change into voltage signal with this current signal; Electric leakage inductor (ZCT) 100 in the utility model links to each other with low pass filter 201, when power line any brings out existing Ground leakage current, electric leakage inductor ZCT changes into voltage signal with this current signal and is sent to low pass filter 201, when electric leakage is pulsating direct current, the signal that inductor produces has high-frequency harmonic, low pass filter 201 can filter this high-frequency harmonic, the utility model is owing to adopted low pass filter, when detecting electric leakage of AC type and the electric leakage of A type, the consistency of action is fine, and A type detection of electrical leakage chip does not design low pass filter in the prior art, and the production qualification rate is low, promotes the use of very difficult; The output termination amplifier 202 of low pass filter 201, amplifier 202 links to each other with full-bridge rectification filter unit 203, both are used, because the signal of low pass filter output is very weak, need signal to be amplified, by full-bridge rectification filter unit 203 this AC signal is rectified into dc level signal then, through full-bridge rectification filtering through amplifier 202, electric leakage inductor ZCT just senses, and negative signal all can be detected; The positive input of the output termination first comparator OP1 of full-bridge rectification filter unit 203, the first comparator OP1 meets reference level V1, when if the level of full-bridge rectification filter unit 203 outputs is higher than the reference level V1 of the first comparator OP1, the first comparator OP1 exports high level, by between the first comparator OP1 and the second comparator OP2, being provided with a time-delay constant-current controller 206, an i.e. constant-current source, be used for providing constant electric current to the second comparator OP2, when first comparator output high level, constant-current source charges to second comparator in-phase end; Time-delay regulon 205 is an external capacitor C6, external capacitor C6 one end ground connection, the other end links to each other with the positive input of second comparator OP2, when the positive input power supply of constant-current source to second comparator, because the effect of external capacitor C6, make the voltage of second comparator be increased to the reference level V2 of the second comparator OP2 gradually, this delay time can reach short time delay and two kinds of standards of long delay of GB 16917-2003 through the appearance value of control capacittance C6, when the voltage of capacitor C 6 is raised to the reference level V2 that is higher than the second comparator OP2, the voltage of the positive input of the second comparator OP2 is greater than reference level V2, output high level to the first output unit 207, after making controllable silicon T3 triggering and conducting in the power switch unit 500 by first output unit 207, make the rectifier bridge DCT short circuit that links to each other with controllable silicon, thereby realize the dropout of leakage switch.

Also comprise an external filter circuit in electric-leakage detection circuit 200, this external filter circuit comprises resistance R 2 and capacitor C 1, resistance R 2 and capacitor C 1 back in parallel one end ground connection, and another termination full-bridge rectification filter unit 203 is used to increase the antijamming capability of circuit.

Overvoltage refers to line voltage and is higher than rated value, domestic power grid voltage according to national regulation is interchange 230V ± 10%, frequency is the 50HZ sinusoidal ac, because the fluctuation or the fault of electrical network, cause line voltage to be higher than rated value, if this voltage is used on the general household electrical appliance, can damages household electrical appliance; Overvoltage protection is exactly in the time of overtension, can allow protection switch thread off.

The utility model power input unit 300 comprises a rectifier bridge DCT, AC power L and N end connect the two ends of rectifier bridge DCT respectively, voltage sampling unit 401 links to each other with power input unit 300, voltage sampling unit 401 comprises divider resistance R6 and divider resistance R7, the termination rectifier bridge DCT of divider resistance R6, the divider resistance R6 other end is connected with divider resistance R7 and is passed through divider resistance R7 ground connection, divider resistance R7 integrator 402 in parallel, integrator 402 is a capacitor C 5, sampling voltage is in the C5 upper integral, sampling voltage is become stable DC voltage, be connected to the positive input of voltage detector 403 by the tie point between divider resistance R6 and the divider resistance R7; When voltage detector 403 detected integration level are higher than voltage detector 403 inner threshold values 4.5V ± 2%, voltage detector 403 can be given connected delay unit 404 by the output high level, the delay time of delay unit 404 is 50mS, after just the electrical network abnormal pressure kept 50mS, delay unit 404 was just exported high level to the second output unit 405; This delay function can effectively be got rid of voltage ripple of power network and misoperation; Second output unit 405 (being that T2 is a metal-oxide-semiconductor) is in conducting under the high level at delay unit 404, makes controllable silicon T3 triggering and conducting in the power switch unit 500 then, makes the rectifier bridge DCT short circuit that links to each other with controllable silicon, thereby realizes the dropout of leakage switch.

It should be noted that, above embodiment is only unrestricted in order to the explanation the technical solution of the utility model, although the utility model is had been described in detail with reference to preferred embodiment, those of ordinary skill in the art is to be understood that, can make amendment or be equal to replacement the technical solution of the utility model, and not breaking away from the spirit and scope of technical solutions of the utility model, it all should be encompassed in the middle of the claim scope of the present utility model.

Claims

1. a pulsating direct current electric leakage and an over-pressure safety device that is used for earth leakage circuit-breaker is characterized in that: comprise electric leakage inductor, electric-leakage detection circuit, power input unit, over-voltage detection circuit, power switch unit; The output of inductor of wherein leaking electricity is connected with the input of electric-leakage detection circuit, and the output of electric-leakage detection circuit is connected with the input of power switch unit; The output of described power input unit is connected the back and links to each other with power switch unit with over-voltage detection circuit.

2. pulsating direct current electric leakage and the over-pressure safety device that is used for earth leakage circuit-breaker according to claim 1 is characterized in that: described electric-leakage detection circuit comprises low pass filter, amplifier, full-bridge rectification filter unit, first comparator, second comparator and first output unit; Wherein the input termination leakage inductance of low pass filter is answered the output of device, and the output of low pass filter connects amplifier, full-bridge rectification filter unit, first comparator, second comparator and first output unit successively.

3. pulsating direct current electric leakage and the over-pressure safety device that is used for earth leakage circuit-breaker according to claim 2; it is characterized in that: described electric-leakage detection circuit also comprises the time-delay constant-current controller, and described time-delay constant-current controller is between described first comparator and second comparator.

4. pulsating direct current electric leakage and the over-pressure safety device that is used for earth leakage circuit-breaker according to claim 2; it is characterized in that: described electric-leakage detection circuit also comprises the time-delay regulon; described time-delay regulon is an external capacitor C6; described external capacitor C6 one end ground connection, the other end connects the positive input of described second comparator.

5. pulsating direct current electric leakage and the over-pressure safety device that is used for earth leakage circuit-breaker according to claim 2; it is characterized in that: described electric-leakage detection circuit also comprises an external filter circuit; described external filter circuit comprises a resistance R 2 and a capacitor C 1, described resistance R 2 and capacitor C 1 back in parallel one end ground connection, the described full-bridge rectification filter unit of another termination.

6. pulsating direct current electric leakage and the over-pressure safety device that is used for earth leakage circuit-breaker according to claim 1; it is characterized in that: described over-voltage detection circuit comprises voltage sampling unit, integrator, voltage detector, delay unit and second output unit; the described power input unit of input termination of described voltage sampling unit, the output of voltage sampling unit connects integrator, voltage detector, delay unit, second output unit successively.

7. pulsating direct current electric leakage and the over-pressure safety device that is used for earth leakage circuit-breaker according to claim 6; it is characterized in that: described voltage sampling unit comprises the first divider resistance R6 and the second divider resistance R7; the described power input unit of a termination of the described first divider resistance R6; ground connection after the other end of the first divider resistance R6 is connected with the second divider resistance R7, the described second divider resistance R7 is in parallel with integrator.