CN107436391A - Ground fault detection device - Google Patents
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Abstract
Description
技术领域technical field
本发明属于电力系统监测控制领域，涉及接地技术。The invention belongs to the field of power system monitoring and control, and relates to grounding technology.
背景技术Background technique
在给负载供电时三孔插座被广泛应用，三孔插座的三孔成等腰三角形，顶角孔垂直向上，与公用地线或公用接零线连接，不同插座的地线(或零线)只能并联，不得串联，两腰的两个底角孔左边接零线，右边接火线。Three-hole sockets are widely used when supplying power to loads. The three holes of the three-hole socket form an isosceles triangle, and the top corner holes are vertically upward. It can only be connected in parallel, not in series. The left side of the two bottom corner holes on the two waists is connected to the neutral wire, and the right side is connected to the live wire.
在实际应用中当家用电器严重漏电时，特别是发生短路性漏电时，负载电器的保护接地与变压器的工作接地对给负载电器供电的单相电源形成短路，只要此时线路中的电流达到保险丝的熔断电流，火线上的保险丝就会迅速熔断，使严重漏电的负载电器切断电源。In practical applications, when household electrical appliances are seriously leaking, especially when short-circuit leakage occurs, the protective grounding of the load electrical appliance and the working grounding of the transformer form a short circuit to the single-phase power supply for the load electrical appliance, as long as the current in the line reaches the fuse If the fusing current is high, the fuse on the live line will blow quickly, so that the load electrical appliances with serious leakage will cut off the power supply.
采用这种漏电保护机制，只有当漏电严重到一定程度下才能使保险丝熔断，若只是轻微漏电，保险丝未能达到熔断程度，则负载电器会一直处于非正常工作状态，长期处于这种工作状态会令负载电器缩减使用寿命，而使用人员并不知晓漏电情况的存在，并不能及时解决轻微漏电状态。With this kind of leakage protection mechanism, the fuse can only be blown when the leakage is serious enough to a certain extent. The service life of the load electrical appliances is shortened, and the user does not know the existence of the leakage situation, and cannot solve the slight leakage state in time.
发明内容Contents of the invention
本发明目的是为了解决采用保险丝熔断方式进行漏电保护存在的问题，提供了一种接地故障监测装置。The object of the present invention is to provide a ground fault monitoring device to solve the problems existing in leakage protection by means of fuse blowing.
本发明所述接地故障监测装置包括NE555时基集成电路、断路器QS、氖灯NH、电流互感器TA、电阻R1～R6、滑动变阻器RP、电容C1～C2、二极管VD1～VD4、三极管VT1～VT2、稳压二极管VS、喇叭BL、交流接触器KM和中间继电器KA；The ground fault monitoring device of the present invention includes NE555 time base integrated circuit, circuit breaker QS, neon lamp NH, current transformer TA, resistors R1~R6, sliding rheostat RP, capacitors C1~C2, diodes VD1~VD4, triodes VT1~ VT2, Zener diode VS, horn BL, AC contactor KM and intermediate relay KA;
220V交流电源通过断路器QS、交流接触器KM常开主触点为负载供电；在断路器QS、交流接触器KM常开主触点之间供电线路的火线L分别连接三孔插座CZ的一个等腰插孔和二极管VD3的阴极；零线N分别连接三孔插座CZ的另一个等腰插孔和二极管VD4的阴极；The 220V AC power supplies power to the load through the normally open main contact of the circuit breaker QS and the AC contactor KM; the live wire L of the power supply line between the circuit breaker QS and the normally open main contact of the AC contactor KM is respectively connected to one of the three-hole socket CZ The isosceles jack and the cathode of the diode VD3; the neutral line N is respectively connected to the other isosceles jack of the three-hole socket CZ and the cathode of the diode VD4;
三孔插座CZ的顶孔连接的地线上套有电流互感器TA的初级线圈；三孔插座CZ的顶孔连接氖灯NH的一端，氖灯NH的另一端同时连接电阻R3的一端和电阻R4的一端，电阻R3的另一端连接二极管VD3的阳极，电阻R4的另一端连接二极管VD4的阳极；The ground wire connected to the top hole of the three-hole socket CZ is covered with the primary coil of the current transformer TA; the top hole of the three-hole socket CZ is connected to one end of the neon lamp NH, and the other end of the neon lamp NH is connected to one end of the resistor R3 and the resistor One end of R4, the other end of resistor R3 is connected to the anode of diode VD3, and the other end of resistor R4 is connected to the anode of diode VD4;
电流互感器TA次级线圈的一端同时连接电容C1的一端、三极管VT1的发射极、稳压二极管VS的阳极、中间继电器KA常开触点的一端、NE555时基集成电路的1脚、电容C2的一端和喇叭BL的负极供电端子，并接地；One end of the secondary coil of the current transformer TA is simultaneously connected to one end of the capacitor C1, the emitter of the triode VT1, the anode of the Zener diode VS, one end of the normally open contact of the intermediate relay KA, pin 1 of the NE555 time base integrated circuit, and capacitor C2 One end and the negative power supply terminal of the speaker BL, and grounded;
电流互感器TA次级线圈的另一端连接二极管VD1的阳极，二极管VD1的阴极连接滑动变阻器RP的一个固定端，滑动变阻器RP的另一个固定端及其活动端同时连接电容C1的另一端和三极管VT1的基极，三极管VT1的集电极同时连接电阻R1的一端和中间继电器KA线圈的一端；The other end of the secondary coil of the current transformer TA is connected to the anode of the diode VD1, the cathode of the diode VD1 is connected to a fixed end of the sliding rheostat RP, and the other fixed end of the sliding rheostat RP and its movable end are connected to the other end of the capacitor C1 and the transistor The base of VT1 and the collector of triode VT1 are simultaneously connected to one end of the resistor R1 and one end of the coil of the intermediate relay KA;
电阻R1的另一端连接三极管VT2的基极，三极管VT2的发射极同时连接稳压二极管VS的阴极和电阻R2的一端，三极管VT2的集电极同时连接交流接触器KM线圈的一端和二极管VD2的阳极；The other end of the resistor R1 is connected to the base of the triode VT2, the emitter of the triode VT2 is connected to the cathode of the Zener diode VS and one end of the resistor R2, and the collector of the triode VT2 is connected to one end of the coil of the AC contactor KM and the anode of the diode VD2 ;
+6V直流电源同时连接中间继电器KA线圈的另一端、交流接触器KM线圈的另一端、二极管VD2的阴极、电阻R2的另一端、电阻R5的一端、NE555时基集成电路的4脚和8脚；The +6V DC power supply is simultaneously connected to the other end of the KA coil of the intermediate relay, the other end of the AC contactor KM coil, the cathode of the diode VD2, the other end of the resistor R2, one end of the resistor R5, pin 4 and pin 8 of the NE555 time base integrated circuit ;
NE555时基集成电路的7脚同时连接电阻R5的另一端和电阻R6的一端；Pin 7 of the NE555 time base integrated circuit is connected to the other end of the resistor R5 and one end of the resistor R6 at the same time;
NE555时基集成电路的2脚、6脚同时连接电阻R6的另一端和中间继电器KA常开触点的另一端；Pin 2 and pin 6 of the NE555 time base integrated circuit are simultaneously connected to the other end of the resistor R6 and the other end of the normally open contact of the intermediate relay KA;
NE555时基集成电路的5脚连接电容C2的另一端；Connect pin 5 of the NE555 time base integrated circuit to the other end of capacitor C2;
NE555时基集成电路的3脚连接喇叭BL的正极供电端子。Pin 3 of the NE555 time base integrated circuit is connected to the positive power supply terminal of the speaker BL.
优选地，+6V直流电源取自断路器QS、交流接触器KM常开主触点之间供电线路，火线L和零线N分别接变压器T原边线圈的两端，变压器T副边线圈的两端分别接整流桥UR的两个交流输入端，整流桥UR的正极电源输出端输出+6V直流电源，整流桥UR的负极电源输出端接地。Preferably, the +6V DC power supply is taken from the power supply line between the normally open main contacts of the circuit breaker QS and the AC contactor KM, the live wire L and the neutral wire N are connected to the two ends of the primary coil of the transformer T, and the secondary coil of the transformer T The two ends are respectively connected to the two AC input terminals of the rectifier bridge UR, the positive power output terminal of the rectifier bridge UR outputs +6V DC power, and the negative power output terminal of the rectifier bridge UR is grounded.
优选地，整流桥UR为采用四只二极管构成的单相桥式整流电路。Preferably, the rectifier bridge UR is a single-phase bridge rectifier circuit composed of four diodes.
本发明的有益效果：本发明所述接地故障监测装置采用简单实用的分立元件搭建而成，性能稳定，当检测到零线(地线)发生漏电的接地故障时，令氖灯发光、喇叭报警，同时切断给负载的电源供给，以便及时进行漏电维修，以保证负载的使用安全及使用寿命。Beneficial effects of the present invention: the ground fault monitoring device of the present invention is built with simple and practical discrete components, and has stable performance. When a ground fault of leakage occurs in the neutral wire (ground wire) is detected, the neon lamp lights up and the horn gives an alarm , and cut off the power supply to the load at the same time, so as to carry out leakage maintenance in time to ensure the safety and service life of the load.
附图说明Description of drawings
图1是本发明所述接地故障监测装置的电路原理图。Fig. 1 is a schematic circuit diagram of the ground fault monitoring device of the present invention.
具体实施方式detailed description
以下将结合附图及实施例来详细说明本发明的实施方式，借此对本发明如何应用技术手段来解决技术问题，并达成技术效果的实现过程能充分理解并据以实施。需要说明的是，只要不构成冲突，本发明中的各个实施例以及各实施例中的各个特征可以相互结合，所形成的技术方案均在本发明的保护范围之内。The implementation of the present invention will be described in detail below in conjunction with the accompanying drawings and examples, so as to fully understand and implement the process of how to apply technical means to solve technical problems and achieve technical effects in the present invention. It should be noted that, as long as there is no conflict, each embodiment and each feature in each embodiment of the present invention can be combined with each other, and the formed technical solutions are all within the protection scope of the present invention.
实施例：接地故障监测装置包括NE555时基集成电路、断路器QS、氖灯NH、电流互感器TA、电阻R1～R6、滑动变阻器RP、电容C1～C2、二极管VD1～VD4、三极管VT1～VT2、稳压二极管VS、喇叭BL、交流接触器KM和中间继电器KA；Embodiment: The ground fault monitoring device includes NE555 time-base integrated circuit, circuit breaker QS, neon lamp NH, current transformer TA, resistors R1-R6, sliding rheostat RP, capacitors C1-C2, diodes VD1-VD4, triodes VT1-VT2 , Zener diode VS, speaker BL, AC contactor KM and intermediate relay KA;
220V交流电源通过断路器QS、交流接触器KM常开主触点为负载供电；在断路器QS、交流接触器KM常开主触点之间供电线路的火线L分别连接三孔插座CZ的一个等腰插孔和二极管VD3的阴极；零线N分别连接三孔插座CZ的另一个等腰插孔和二极管VD4的阴极；The 220V AC power supplies power to the load through the normally open main contact of the circuit breaker QS and the AC contactor KM; the live wire L of the power supply line between the circuit breaker QS and the normally open main contact of the AC contactor KM is respectively connected to one of the three-hole socket CZ The isosceles jack and the cathode of the diode VD3; the neutral line N is respectively connected to the other isosceles jack of the three-hole socket CZ and the cathode of the diode VD4;
三孔插座CZ的顶孔连接的地线上套有电流互感器TA的初级线圈；三孔插座CZ的顶孔连接氖灯NH的一端，氖灯NH的另一端同时连接电阻R3的一端和电阻R4的一端，电阻R3的另一端连接二极管VD3的阳极，电阻R4的另一端连接二极管VD4的阳极；The ground wire connected to the top hole of the three-hole socket CZ is covered with the primary coil of the current transformer TA; the top hole of the three-hole socket CZ is connected to one end of the neon lamp NH, and the other end of the neon lamp NH is connected to one end of the resistor R3 and the resistor One end of R4, the other end of resistor R3 is connected to the anode of diode VD3, and the other end of resistor R4 is connected to the anode of diode VD4;
电流互感器TA次级线圈的一端同时连接电容C1的一端、三极管VT1的发射极、稳压二极管VS的阳极、中间继电器KA常开触点的一端、NE555时基集成电路的1脚、电容C2的一端和喇叭BL的负极供电端子，并接地；One end of the secondary coil of the current transformer TA is simultaneously connected to one end of the capacitor C1, the emitter of the triode VT1, the anode of the Zener diode VS, one end of the normally open contact of the intermediate relay KA, pin 1 of the NE555 time base integrated circuit, and capacitor C2 One end and the negative power supply terminal of the speaker BL, and grounded;
电流互感器TA次级线圈的另一端连接二极管VD1的阳极，二极管VD1的阴极连接滑动变阻器RP的一个固定端，滑动变阻器RP的另一个固定端及其活动端同时连接电容C1的另一端和三极管VT1的基极，三极管VT1的集电极同时连接电阻R1的一端和中间继电器KA线圈的一端；The other end of the secondary coil of the current transformer TA is connected to the anode of the diode VD1, the cathode of the diode VD1 is connected to a fixed end of the sliding rheostat RP, and the other fixed end of the sliding rheostat RP and its movable end are connected to the other end of the capacitor C1 and the transistor The base of VT1 and the collector of triode VT1 are simultaneously connected to one end of the resistor R1 and one end of the coil of the intermediate relay KA;
电阻R1的另一端连接三极管VT2的基极，三极管VT2的发射极同时连接稳压二极管VS的阴极和电阻R2的一端，三极管VT2的集电极同时连接交流接触器KM线圈的一端和二极管VD2的阳极；The other end of the resistor R1 is connected to the base of the triode VT2, the emitter of the triode VT2 is connected to the cathode of the Zener diode VS and one end of the resistor R2, and the collector of the triode VT2 is connected to one end of the coil of the AC contactor KM and the anode of the diode VD2 ;
+6V直流电源同时连接中间继电器KA线圈的另一端、交流接触器KM线圈的另一端、二极管VD2的阴极、电阻R2的另一端、电阻R5的一端、NE555时基集成电路的4脚和8脚；The +6V DC power supply is simultaneously connected to the other end of the KA coil of the intermediate relay, the other end of the AC contactor KM coil, the cathode of the diode VD2, the other end of the resistor R2, one end of the resistor R5, pin 4 and pin 8 of the NE555 time base integrated circuit ;
NE555时基集成电路的7脚同时连接电阻R5的另一端和电阻R6的一端；Pin 7 of the NE555 time base integrated circuit is connected to the other end of the resistor R5 and one end of the resistor R6 at the same time;
NE555时基集成电路的2脚、6脚同时连接电阻R6的另一端和中间继电器KA常开触点的另一端；Pin 2 and pin 6 of the NE555 time base integrated circuit are simultaneously connected to the other end of the resistor R6 and the other end of the normally open contact of the intermediate relay KA;
NE555时基集成电路的5脚连接电容C2的另一端；Connect pin 5 of the NE555 time base integrated circuit to the other end of capacitor C2;
NE555时基集成电路的3脚连接喇叭BL的正极供电端子。Pin 3 of the NE555 time base integrated circuit is connected to the positive power supply terminal of the speaker BL.
工作原理：当三孔插座CZ正常工作无漏电时，地线上无电流，则氖灯NH不亮，电流互感器TA感觉不到电流，则VT1基极无偏置电压，VT1截止，KA线圈两端均为高电压，KA线圈不得电，KA常开触点保持断开，NE555的6脚输入电压为高电平，则NE555的3脚输出低电平，喇叭BL不响；由于VT1集电极为高电压，则VT2基极加载偏置电压导通，KM线圈得电，其常开主触点闭合，220V电源正常为负载供电。Working principle: When the three-hole socket CZ works normally without leakage and there is no current on the ground wire, the neon lamp NH does not light up, and the current transformer TA does not feel the current, then there is no bias voltage at the base of VT1, VT1 is cut off, and the KA coil Both ends are high voltage, the KA coil is not powered, the KA normally open contact remains disconnected, the input voltage of pin 6 of NE555 is high level, then the output voltage of pin 3 of NE555 is low level, and the speaker BL does not sound; When the electrode is at high voltage, the VT2 base is loaded with a bias voltage and turned on, the KM coil is energized, its normally open main contact is closed, and the 220V power supply normally supplies power to the load.
当三孔插座CZ出现漏电时，地线上出现短路电流，漏电电流经由三孔插座CZ的接地端和R3(R4)、VD3(VD4)与火线L(零线N)形成回路，NH发光，同时该漏电电流被TA检测到，TA的次级输出电流，该电流经VD1整流，使VT1由截止翻转为导通，而VT2则由导通翻转为截止。此时，KA线圈得电，而KM线圈失电，则KA常开触点闭合，NE555的2脚输入低电平，则NE555的3脚输出高电平，喇叭BL进行声音报警；KM常开主触点恢复断开，切断220V电源为负载的供电回路。When there is leakage in the three-hole socket CZ, a short-circuit current appears on the ground wire, and the leakage current forms a loop through the ground terminal of the three-hole socket CZ, R3 (R4), VD3 (VD4) and the live wire L (neutral wire N), and NH emits light. At the same time, the leakage current is detected by TA, and the secondary output current of TA is rectified by VD1, so that VT1 turns from off to on, and VT2 turns from on to off. At this time, the KA coil is energized, and the KM coil is de-energized, the KA normally open contact is closed, the 2 pin of NE555 inputs a low level, then the NE555 pin 3 outputs a high level, and the speaker BL sounds an alarm; KM normally open The main contact is restored and disconnected, and the 220V power supply is cut off for the power supply circuit of the load.
基于上述分析，本实施方式这种技术手段使得只要三孔插座出现漏电，即进行声光报警，提醒进行维修，同时切断供电回路来保护负载的用电安全。Based on the above analysis, the technical means of this embodiment makes it possible to give an audible and visual alarm as soon as there is leakage in the three-hole socket to remind maintenance, and at the same time cut off the power supply circuit to protect the safety of the load.
虽然本发明所揭露的实施方式如上，但所述的内容只是为了便于理解本发明而采用的实施方式，并非用以限定本发明。任何本发明所属技术领域内的技术人员，在不脱离本发明所揭露的精神和范围的前提下，可以在实施的形式上及细节上作任何的修改与变化，但本发明的专利保护范围，仍须以所附的权利要求书所界定的范围为准。Although the embodiments disclosed in the present invention are as above, the described content is only an embodiment adopted for the convenience of understanding the present invention, and is not intended to limit the present invention. Anyone skilled in the technical field to which the present invention belongs can make any modifications and changes in the form and details of the implementation without departing from the spirit and scope disclosed by the present invention, but the patent protection scope of the present invention, The scope defined by the appended claims must still prevail.
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| CN110297151A (en) * | 2019-05-24 | 2019-10-01 | 温州华亚电气有限公司 | A kind of observation circuit protection circuit of ground fault earth leakage protective device operation troubles |
| CN112909891A (en) * | 2020-10-15 | 2021-06-04 | 广东骉马机器人科技有限公司 | Leakage protection system and method |
| CN116782555A (en) * | 2023-06-25 | 2023-09-19 | 国网黑龙江省电力有限公司黑河供电公司 | Electric switch cabinet with anti-leakage and safe door-opening function |
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| US4494162A (en) * | 1981-10-30 | 1985-01-15 | Harsco Corporation | Starter thermal overload protection system |
| CN1072294A (en) * | 1991-11-08 | 1993-05-19 | 南京航空学院 | Multi-function automatic monitor for power consumption |
| CN103364688A (en) * | 2012-03-30 | 2013-10-23 | 海洋王（东莞）照明科技有限公司 | Three-jack socket electric leakage detection circuit |
| CN203747164U (en) * | 2013-11-27 | 2014-07-30 | 昆明理工大学 | Socket |
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| CN206148928U (en) * | 2016-11-23 | 2017-05-03 | 高雅琦 | Power transformer's zero -sequence protection circuit |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN110297151A (en) * | 2019-05-24 | 2019-10-01 | 温州华亚电气有限公司 | A kind of observation circuit protection circuit of ground fault earth leakage protective device operation troubles |
| CN110297151B (en) * | 2019-05-24 | 2022-04-08 | 温州华亚电气有限公司 | Monitoring circuit protection circuit for operation fault of earth fault leakage protector |
| CN112909891A (en) * | 2020-10-15 | 2021-06-04 | 广东骉马机器人科技有限公司 | Leakage protection system and method |
| CN116782555A (en) * | 2023-06-25 | 2023-09-19 | 国网黑龙江省电力有限公司黑河供电公司 | Electric switch cabinet with anti-leakage and safe door-opening function |
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