阅读说明：本技术 剩余电流动作（漏电）保护单稳延时控制系统 (residual current action (leakage) protection monostable delay control system ) 是由 尚峻立 尚于统 周凡 张丁嘉 于 2019-08-26 设计创作，主要内容包括：本发明提供一种剩余电流动作(漏电)保护单稳延时控制系统,包括集成电路、零序互感器ZCT、整流电路、执行机构(脱扣装置)、断路器、晶闸管以及单稳延时电路；整流电路的交流输入端与断路器的电源连接,整流电路的直流输出端通过所述执行机构(脱扣装置)与晶闸管串联连接形成回路；单稳延时电路包括充、放电电阻R6、开关二极管D10以及充、放电电容C4,充、放电电阻R6与开关二极管D10并联再与电容C4串联给电容C4充、放电过程完成延时输出,所述单稳延时电路的输入端连接在运算放大器的输出端,延时电路的输出端与锁存器的信号输入端连接；所述晶闸管的触发端与锁存器信号输出端连接所述控制系统延时范围宽,抗干扰能力强,制造成本低,通用性强。(The invention provides a monostable delay control system for residual current action (leakage) protection, which comprises an integrated circuit, a zero sequence transformer ZCT, a rectifying circuit, an actuating mechanism (a tripping device), a circuit breaker, a thyristor and a monostable delay circuit, wherein the zero sequence transformer ZCT is connected with the rectifying circuit; the alternating current input end of the rectifying circuit is connected with a power supply of the circuit breaker, and the direct current output end of the rectifying circuit is connected with the thyristor in series through the actuating mechanism (tripping device) to form a loop; the monostable delay circuit comprises a charging resistor R6, a switching diode D10 and a charging capacitor C4, wherein the charging resistor R6 is connected with the switching diode D10 in parallel and then connected with a capacitor C4 in series to complete delay output in the charging and discharging process of the capacitor C4, the input end of the monostable delay circuit is connected with the output end of the operational amplifier, and the output end of the delay circuit is connected with the signal input end of the latch; the trigger end of the thyristor and the signal output end of the latch are connected with the control system, so that the delay range is wide, the anti-interference capability is strong, the manufacturing cost is low, and the universality is strong.)

1. The utility model provides a residual current action (electric leakage) protection monostable delay control system which characterized in that: the zero sequence transformer ZCT circuit comprises an integrated circuit, a zero sequence transformer ZCT, a rectifying circuit, an actuating mechanism (tripping device), a circuit breaker, a thyristor and a monostable delay circuit;

The alternating current input end of the rectifying circuit is connected with a power supply of the circuit breaker, and the direct current output end of the rectifying circuit is connected with the thyristor in series through the actuating mechanism (tripping device) to form a loop;

The integrated circuit comprises an operational amplifier and a latch;

The zero sequence transformer ZCT is connected with the circuit breaker in series, and the secondary side of the zero sequence transformer ZCT is connected with the reverse phase input end and the in-phase input end of the operational amplifier in a loop way;

The monostable delay circuit comprises a charging resistor R6, a discharging resistor D10 and a charging capacitor C4, wherein the charging resistor R6 is connected with the discharging resistor D10 in parallel and then connected with the charging capacitor C4 in series to charge and discharge the charging capacitor C4 and complete delay output in a discharging process;

the trigger end of the thyristor is connected with the signal output end of the latch;

A voltage stabilizing circuit is connected in parallel between the inverting input end and the non-inverting input end of the operational amplifier, and the voltage stabilizing circuit comprises a leakage action value resistor RL which is connected in parallel between the inverting input end and the non-inverting input end of the operational amplifier;

D10 is conducted when the output end of the operational amplifier is at high level, and D10 is cut off when the output end of the operational amplifier is at low level; when the output end of the operational amplifier is at a high level, the R6 and the D10 form a parallel circuit, the switching tube D10 is conducted, and the delay capacitor C4 is rapidly charged through the D10; when the charging of the C4 is completed, the switching tube D10 is cut off, the input end of the latch is changed into high level, the high level output of the output end of the latch triggers the thyristor, the thyristor conduction executing mechanism (tripping device) disconnects the breaker to enable the zero sequence transformer ZCT signal to disappear, the output end of the operational amplifier is changed into low level D10 to be cut off, and the R6 quickly discharges the C4.

2. The residual current operated (earth leakage) protection monostable delay control system of claim 1 characterised in that: the voltage stabilizing circuit further comprises filter capacitors C1 and C3 which are connected in parallel, wherein the filter capacitors C1 and C3 are connected between the inverting input end and the non-inverting input end of the operational amplifier in parallel and are connected with the action value resistor RL in parallel.

3. The residual current operated (earth leakage) protection monostable delay control system of claim 1 characterised in that: the monostable delay control system further comprises a voltage reduction and stabilization circuit which provides a required stabilized voltage supply for the integrated circuit, the voltage reduction and stabilization circuit is connected in the rectification circuit, the voltage reduction and stabilization circuit comprises a voltage reduction resistor R5, a filter capacitor C8 and a voltage stabilization diode W1, and the filter capacitor C8 and the voltage stabilization diode W1 are connected in series and then connected in parallel with the voltage reduction resistor.

4. The residual current operated (earth leakage) protection monostable delay control system of claim 1 characterised in that: the trigger end of the thyristor is also connected in series with a protective resistor R4, the thyristor and the protective resistor R4 are connected in parallel at two ends of a closed loop of the voltage reduction and voltage regulation circuit, and the thyristor and the protective resistor R4 are connected in series between the monostable delay circuit and the loop of the trigger end of the thyristor.

5. The residual current operated (earth leakage) protection monostable delay control system of claim 1 characterised in that: the actuating mechanism (tripping device) can be a signal source such as an L-shaped tripping device, a relay, a light-emitting diode or a buzzer.

6. The residual current operated (earth leakage) protection monostable delay control system of claim 2 characterised in that: the input end of the capacitor C3 is connected in series with a protection resistor R3, a protection resistor R3 and a capacitor C3, and is arranged at two ends of the filter capacitor C1.

Technical Field

The invention relates to the field of circuit breaker leakage protectors, in particular to a residual current action (leakage) protection system.

Background

The residual current operated protector is also called a leakage protector, and is hereinafter referred to as leakage protector. The leakage current tripping device is mainly used for direct or indirect contact protection of electric equipment and circuit leakage protection human beings, poultry and property, and when the leakage current protector detects that the leakage current exceeds a leakage protection specified value, the leakage current tripping device disconnects a main contact of a main circuit, a load is disconnected, and potential safety hazards caused by leakage are avoided. In recent years, the leakage protector is widely popularized and applied in China, the current leakage protector for China is very popular, the number of people suffering electric shock injuries and deaths is greatly reduced compared with that of the people suffering electric shock injuries and deaths in the past years, and the number of people suffering electric shock death in the whole nation is reduced to about 8000 people every year according to 2016 year data of the national statistical bureau. Therefore, the earth leakage protector is a good defender which protects the safety of human life and property at any moment and in a silently way.

The existing commonly used leakage circuit breakers are divided into a voltage type and a current type, the current type is divided into an electromagnetic type and an electronic type, the leakage circuit breakers in the current market are provided, an electronic control module is a called integrated board which takes special leakage integration (with non-delay IC8 pin encapsulation and with delay IC16 pin encapsulation) as core control, the integrated board is divided into a delay type and a non-delay type, a thyristor is taken as a core, and the called discrete board is not controlled by an integrated circuit IC and can achieve the function of leakage protection.

the non-delay type integrated board mainly has a control module formed by discrete electronic components and an 8-pin packaged Integrated Circuit (IC) without a delay function, and the 8-pin packaged Integrated Circuit (IC) includes: 54123. 54123A, and the like. The functions or the pin functions similar to 54123 are improved on the basis of 54123.

The leakage protection 54123 delay circuit in the market is connected with the input end of the latch in a direct short circuit way at the output end of the operational amplifier, a capacitor is added between the two short circuit connections and the ground wire, and the capacitor is directly charged and discharged. The delay protector and the non-delay protector produced on the market at present are two kinds of integrated circuit IC chips, and the leakage protection chip with the delay function has the defects of high cost (IC16 pin package), large volume, more stocks and the like. The delay type integrated board mainly has a control module formed by a 16-pin packaged Integrated Circuit (IC) with a delay function, and the 16-pin packaged Integrated Circuit (IC) has the following examples: 54133. 54133A, and so on.

The leakage protector frequently appears the mistake operating phenomenon of stepping over in the existing market, specifically for safe and reliable reasonable power consumption: the circuit protection is divided into a first-level protection, a second-level protection, a third-level protection, a terminal protection and other multi-stage protection levels, and if the action time of the multi-stage leakage protector is consistent or close, the multi-stage leakage protector can synchronously or overridely act. And great loss is caused to real life and production.

therefore, how to provide a control system with low cost, strong versatility and high sensitivity, which can not only avoid the malfunction of the product, but also ensure the normal leakage delay protection function of the product, is a problem to be solved by those skilled in the art.

Disclosure of Invention

In view of the above, the technical problems to be solved by the present invention are that the leakage protector in the prior art has low versatility, insensitive response, and easy occurrence of synchronous or override actions of the leakage protector. Therefore, the invention provides a residual current action (leakage) protection monostable delay control system.

in order to achieve the purpose, the invention provides the following technical scheme:

The utility model provides a residual current action (electric leakage) protection monostable delay control system which characterized in that: the zero sequence transformer ZCT circuit comprises an integrated circuit, a zero sequence transformer ZCT, a rectifying circuit, an actuating mechanism (tripping device), a circuit breaker, a thyristor and a monostable delay circuit;

the alternating current input end of the rectifying circuit is connected with a power supply of the circuit breaker, and the direct current output end of the rectifying circuit is connected with the thyristor in series through the actuating mechanism (tripping device) to form a loop;

The integrated circuit comprises an operational amplifier and a latch;

The zero sequence transformer ZCT is connected with the circuit breaker in series, and the secondary side of the zero sequence transformer ZCT is connected with the reverse phase input end and the in-phase input end of the IC operational amplifier in a loop way;

The monostable delay circuit comprises a charging resistor R6, a discharging resistor D10 and a charging capacitor C4, wherein the charging resistor R6 is connected with the discharging resistor D10 in parallel and then connected with the charging capacitor C4 in series to charge and discharge the charging capacitor C4 and complete delay output in a discharging process;

The trigger end of the thyristor is connected with the signal output end of the latch;

A voltage stabilizing circuit is connected in parallel between the inverting input end and the non-inverting input end of the operational amplifier, and the voltage stabilizing circuit comprises a leakage action value resistor RL which is connected in parallel between the inverting input end and the non-inverting input end of the operational amplifier;

D10 is conducted when the output end of the operational amplifier is at high level, and D10 is cut off when the output end of the operational amplifier is at low level; when the output end of the operational amplifier is at a high level, the R6 and the D10 form a parallel circuit, and the switching tube D10 is conducted to quickly charge the delay capacitor C4 through the D10; when the charging of the C4 is completed, the switching tube D10 is cut off, the input end of the latch is changed into a high level output trigger thyristor at the output end of the high level latch, a thyristor conduction executing mechanism (tripping device) disconnects the breaker to enable a zero sequence transformer ZCT signal to disappear, the output end of the operational amplifier is changed into a low level D10 to be cut off, and the R6 quickly discharges the C4.

In one embodiment of the invention, the voltage stabilizing circuit further comprises filter capacitors C1 and C3 which are connected in parallel, wherein the filter capacitors C1 and C3 are connected in parallel between the inverting input end and the non-inverting input end of the operational amplifier and are connected in parallel with the action value resistor RL.

in an embodiment of the present invention, the monostable delay control system further includes a voltage reduction and stabilization circuit for providing a required stabilized voltage supply for the integrated circuit, the voltage reduction and stabilization circuit is connected in the rectification circuit, the voltage reduction and stabilization circuit includes a voltage reduction resistor R5, a filter capacitor C8, and a voltage stabilization diode W1, and the filter capacitor C8 and the voltage stabilization diode W1 are connected in series and then connected in parallel with the voltage reduction resistor.

In an embodiment of the invention, the trigger end of the thyristor is further connected in series with a protection resistor R4, the thyristor and the protection resistor R4 are connected in parallel at two ends of a closed loop of the voltage reduction and regulation circuit, and the thyristor and the protection resistor R4 are connected in series between the monostable delay circuit and a loop of the trigger end of the thyristor.

In one embodiment of the present invention, the actuator (trip device) may be a signal source such as an L-trip, a relay, a light emitting diode, or a buzzer.

In one embodiment of the present invention, the input end of the capacitor C3 is connected in series with a protection resistor R3, a protection resistor R3 and a capacitor C3, and is connected between the two ends of the filter capacitor C1.

The invention has the beneficial effects that: by arranging the monostable delay circuit, D10 is switched on when the output end of the operational amplifier is at a high level, and D10 is switched off when the output end of the operational amplifier is at a low level; when the output end of the operational amplifier is at a high level, R6 and D10 form a parallel circuit, and C4 is quickly charged through D10; when the charging of the C4 is completed, the latch triggers an actuating mechanism (tripping device) to make a zero sequence transformer ZCT signal disappear, the output end of the operational amplifier becomes a low level, and at the moment, the D10 is cut off to rapidly discharge to the C4; the control system adopts the integrated circuit IC with small volume, the time delay circuit and the non-time delay circuit are completed on the same integrated circuit, and the time delay can be completed without replacing an IC chip, so that the leakage protection circuit is safer, more reasonable, more accurate in time delay, more stable and reliable, wider in application scene, wide in time delay range, strong in anti-interference capability, low in manufacturing cost and strong in universality, and great convenience is brought to the inventory of manufacturers and the selectivity of users; the control system adds a monostable delay circuit on the basis of the output end of an operational amplification comparator and the input end of a latch in a non-delay integrated circuit to form an electronic module with a delay integrated function, and has the advantages of small volume, stable and reliable work, low cost and wider application.

Drawings

in order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a circuit schematic block diagram of a residual current (leakage) protection monostable delay control system according to the present invention.

Fig. 2 is a schematic diagram of the residual current (leakage) protection monostable delay control system of the present invention.

fig. 3 is another embodiment of the monostable delay circuit of the control system of the invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The invention will be further described with reference to the accompanying drawings.

The core of the invention is to provide a control system which has low cost and high sensitivity, can avoid the override misoperation of a product and simultaneously ensure the normal leakage delay protection function of the product, so as to simultaneously solve the problems in the prior art.

the embodiments described below do not limit the contents of the invention described in the claims. The entire contents of the configurations shown in the following embodiments are not limited to those required as solutions of the inventions described in the claims.

as shown in the attached drawings 1-3, the invention discloses a residual current action (leakage) protection monostable delay control system, which comprises an integrated circuit, a zero sequence mutual inductor ZCT, a rectification circuit, an actuating mechanism (tripping device), a circuit breaker, a thyristor and a monostable delay circuit; the alternating current input end of the rectifying circuit is connected with a power supply of the circuit breaker, and the direct current output end of the rectifying circuit is connected with the thyristor in series through the actuating mechanism (tripping device); the integrated circuit comprises an operational amplifier and a latch; the zero sequence transformer ZCT is connected with the circuit breaker in series, and the secondary side of the zero sequence transformer ZCT is connected with the reverse phase input end and the in-phase input end of the operational amplifier in a loop way; the monostable delay circuit comprises a charging resistor R6, a switching diode D10 and a charging capacitor C4, wherein the charging resistor R6 is connected with the switching diode D10 in parallel and then is connected with the charging capacitor C4 in series, the input end of the monostable delay circuit is connected with the output end of the operational amplifier, and the output end of the delay circuit is connected with the signal input end of the latch; the trigger end of the thyristor is connected with the signal output end of the latch; and a voltage stabilizing circuit is connected in parallel between the inverting input end and the non-inverting input end of the operational amplifier, and the voltage stabilizing circuit comprises an action value resistor RL which is connected in parallel between the inverting input end and the non-inverting input end of the operational amplifier. In this embodiment, the zero sequence transformer ZCT is disposed at a load end of the circuit breaker for illustration. And a test switch is connected between the breaker and the zero sequence transformer ZCT.

D10 is conducted when the output end of the operational amplifier is at high level, and D10 is cut off when the output end of the operational amplifier is at low level; when the output end of the operational amplifier is at high level, R6 and D10 form a parallel circuit, and C4 is quickly charged through D10; when the charging of the C4 is completed, the latch triggers an actuating mechanism (tripping device) to make a zero sequence transformer ZCT signal disappear, the output end of the operational amplifier becomes a low level D10 and is cut off, and the fast C4 is discharged.

Specifically, as shown in fig. 2, the voltage regulator circuit further includes filter capacitors C1 and C3 connected in parallel, and the filter capacitors C1 and C3 are connected in parallel between the inverting input terminal and the non-inverting input terminal of the operational amplifier and connected in parallel with the operation value resistor RL.

Specifically, the monostable delay control system further comprises a voltage reduction and stabilization circuit which is connected in the actuating mechanism (tripping device) and the rectification circuit and is used for providing a required stabilized power supply through the integrated circuit, the voltage reduction and stabilization circuit comprises a voltage reduction resistor R5, a filter capacitor C8 and a voltage stabilization diode W1, and the filter capacitor C8 and the voltage stabilization diode W1 are connected in series and then are connected in parallel with the voltage reduction resistor.

specifically, the trigger end of the thyristor is connected in series with a protection resistor R4, and the thyristor and the protection resistor R4 are connected in series between the trigger end of the thyristor and the circuit of the monostable delay signal output end. That is, the thyristor and the protective resistor R4 are connected in series between the monostable delay circuit and the loop of the trigger end of the thyristor

Specifically, the actuator (trip device) may be an L-shaped trip, a relay, a light emitting diode, or a buzzer. In this embodiment, an L-shaped release is taken as an example for explanation.

Specifically, the input end of the capacitor C3 is connected in series with a protection resistor R3, and the protection resistor R3 is connected in series with the capacitor C3 and then is connected at two ends of the filter capacitor C1.

the working principle is as follows: when the zero sequence transformer detects a leakage signal, the zero sequence transformer generates the leakage signal, the signal generated by the difference of the leakage current is changed, the voltage signal is transmitted to the inverting input end and the non-inverting input end of the operational amplifier through the voltage stabilizing signal conversion circuit to be compared, when the operational amplification reaches a preset value, the output end of the operational amplifier outputs a high level, the high level conducts D1 through the monostable delay circuit, and the resistance value of the resistor of the RL and D1 which are parallel circuits is reduced, so that the C4 can be charged quickly; the latch delay output is completed by the C4 charging process because pin 1 of the D input of latch is low and the latch output is low before the C4 charging is not completed. The delay time of the delayer is directly related to the capacity of the charging capacitor C4 and the resistance value of the R6. When no leakage current occurs at the load end of the control system, the sum of current vectors flowing through the zero sequence current transformer is zero, the secondary output voltage of the zero sequence current transformer is zero, namely, no voltage difference exists between pins 1 and pins 2 at the input end of the operational amplifier, the output end of the latch is in a low level state, and the leakage protection circuit breaker is in an original state; when the load end of the control system generates earth leakage, the zero sequence current transformer detects that leakage current directly flows to the ground from a live wire, the vector voltages of the live wire and zero line current in the zero sequence current transformer are not zero any more, induced voltage exists at the secondary side, voltage difference exists between the inverting input end and the non-inverting input end of the operational amplifier at the moment, when the voltage difference between the inverting input end and the non-inverting input end reaches a preset value of the operational amplifier, the output end of the differential operational amplifier outputs high level, the monostable delayer works, the monostable delayer outputs high level to the input end of the latch, the output end of the latch outputs high level to trigger the thyristor, the thyristor drives a tripping device, the leakage protection circuit breaker is separated from the gate to break the load, personal and property safety is protected, and the zero.

Specifically, the working principle can be further understood by the following formula:

in the following description, the resistance of D10 is abbreviated as R1.

Taking 4148 switching diode as an example: if is 150 mA; 150 Ma; uf ═ 1V; umax is 100V;

(1) When the output end of the operational amplifier is at a high level, R6 and D10 form a parallel circuit, the R1 value is extremely small at the moment according to a parallel circuit formula, and the power supply quickly charges C4;

(2) when the output of the operational amplifier is low, D10 is turned off and discharges quickly to C4.

That is to say: when the output end of the operational amplifier is at a high level, D10 is switched on, when the output end of the operational amplifier is at a low level, D10 is switched off, D10 and R6 form a parallel circuit, at this time, D10 is switched on, the resistance value after D10 is switched on is smaller than R6, C4 is rapidly charged through D10, the current on R6 is very small, when C4 is fully charged, a latch triggers a release to enable a zero sequence transformer signal to disappear, the output end of the operational amplifier becomes at a low level, D10 is switched off, at this time, R6 is a discharge resistor to discharge to rapid C685. The delay time and the discharge time are fast and slow according to the parameter values of R6 and C4. Therefore, the charging and discharging time can be controlled by controlling R6 and C4.

in the control system, when in practical application, the whole monostable delay circuit can be integrated into the Integrated Circuit (IC); the charging and discharging capacitor C4 may be provided separately on the integrated circuit for the convenience of adjusting the charging and discharging time in practical application.

the monostable delay circuit has the advantages of ingenious design, reasonable structure, few components, stable work and reliable delay, can be integrated inside an integrated circuit IC, and can also be externally hung in a peripheral circuit of the existing integrated circuit, thereby solving the problem that the leakage protector frequently has the phenomenon of override misoperation, such as multi-stage hierarchical protection, wherein the first-stage protection of the circuit protection is 0.2S action value, the second-stage protection is 0.15S action value, the third-stage protection is 0.1S action value, the tail-end protection is 0.05S action value, and the like, solving the problem that the leakage protectors at multi-stage action levels have consistent or similar action time, and cannot have the synchronous or override action of the multi-stage leakage protector. The invention adopts the most common 8-pin IC special chip, adds a set of monostable delay circuit, directly replaces the 16-pin IC chip in function and performance, has low cost, strong universality of component stock, small stock of semi-finished devices and finished devices, high sensitivity and high speed, avoids product misoperation and ensures the normal leakage delay protection function of the product. The flexibility is strong, the commonality is strong, and job stabilization is reliable.

further, as shown in fig. 3, the one-shot delay circuit further includes a resistor R2, and the resistor R2 is connected in series with D10 and then connected in parallel with R6. At this moment, the working principle of the monostable delay circuit is as follows: d10 is conducted when the output end of the operational amplifier is at high level, and D10 is cut off when the output end of the operational amplifier is at low level; when the output end of the operational amplifier is at a high level, the high level passes through, D10 and R2 form a series circuit, D10 is conducted to flow to R2 and R6 to form a parallel circuit, the total blocking is reduced, C4 can be charged quickly, when C4 is full, the latch triggers the release to enable a zero sequence transformer signal to disappear, the output end of the operational amplifier is changed to be at a low level, D10 is cut off, the parallel circuit of R2 and R6 is disconnected, and at the moment, R6 is a discharge resistor and discharges C4 quickly. Similarly, the delay time and the discharge time are determined by the values of C4, R2 and R6.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.