CN201146366Y - Shunt-opening tripping type equipment for protecting single-phase short circuit - Google Patents
Shunt-opening tripping type equipment for protecting single-phase short circuit Download PDFInfo
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- CN201146366Y CN201146366Y CNU2008200762128U CN200820076212U CN201146366Y CN 201146366 Y CN201146366 Y CN 201146366Y CN U2008200762128 U CNU2008200762128 U CN U2008200762128U CN 200820076212 U CN200820076212 U CN 200820076212U CN 201146366 Y CN201146366 Y CN 201146366Y
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Abstract
The utility model particularly relates to a shunt trip type single-phase short circuit protection device, belonging to the technical field of a phase line of a single-phase load equipment line and neutral line short protection in low-voltage line electric network. The technical proposal is that the device of the utility model consists of a short circuit switch actuator, an action start mechanism of a short circuit switch and a short circuit detection triggering mechanism. Due to the fact that the current and voltage signals which control and trigger the short circuit protection device is irrelevant to the values of the short circuit current in the electric network, the device solves the problems that the 380/220V electric network in urban area and rural area depends on fuses and short circuit switches taking current as parameters, the circuit is difficult to be cut off in time before the conductors within the protecting range, particularly insulated conductors generates the maximum allowable temperature rise (on fire), so the device puts an end to electrical fire caused by the short circuit of the phase line and the neutral line in the low-voltage electric network. The device can be widely used for automatic protection of the phase line and the neutral line short circuit of terminal single-phase users and a circuit breaker at the position of a three-phase four-line down lead within the range that the protection line is separated from the neutral line in a TT system, a TN-S system and a TN-C-S system with power neutral point being directly grounded.
Description
Technical field
The utility model belongs to the single-phase short circuit protection equipment technical field that is used in the low voltage electric network; relate in particular to a kind of by single-phase 220V electric network terminal load equipment phase line and during neutral line short circuit, can disconnect the shunted exciter tripping type single-phase short circuit protecting equipment of short switch.
Background technology
In low pressure 380/220V electrical network, more huge with the single-phase electrical network of 220V especially, extensively.Not only the power supply of the illumination of living standard of urban and rural population electricity consumption, household electrical appliance needs uniline, party, office of political affairs army, enterprises and institutions, finance, school, commerce and trade, food and drink, hotel etc. need the uniline power supply, and the power devices of industrial and agricultural production also needs uniline.The principal element that influences low-voltage circuit safety, reliable power supply is line insulation, electrical equipment, apparatus insulated and its quality.In the power supply use, any one place goes wrong all will cause the fault of single phase circuit short circuit.Short circuit accident does not singly influence for electricity consumption, also with burning apparatus and circuit and initiation fire, causes the heavy losses of property, even cause great casualties for country, collective, individual.According to statistics, present occur 70% all be because the short trouble of circuit causes with electrification.
At present, the single-phase short circuit protective device that generally uses mainly includes fuse and starts and carries out current coil and be serially connected with protective switch of the short circuit in the circuit.Above-mentioned protective device has characteristics simple in structure, easy to use, but these protective devices---or fusible link is serially connected with on the phase line, or the tripping coil that being used to as shown in Figure 1 starts the mechanical lock buckle 1 of short switch K is serially connected in phase line L.The parameter that promptly is used to start or disconnects short switch all is a current value.Have only when short-circuit current value reaches the operating current of the blowout current of fuse protective device or protective switch of the short circuit, could pass through fusing fuse or solenoid TQ and produce enough big electromagnetic force and start mechanical lock buckle 1 and drive short switch K and move cutting-off of short-circuit circuit.Yet, because the single-phase short circuit impedance loop is bigger, short circuit current is less, above-mentioned single-phase short circuit protective device is difficult at the heat effect that short circuit current produces conductor or connector (insulating layer of conductor burning) the preceding cutting-off of short-circuit electric current (when the short circuit current of the single-phase short circuit of promptly the flowing through protective device solenoid TQ of actuator reached 5-16 times of rated value, mechanical lock buckle 1 can start short switch k and move cutting-off of short-circuit circuit in 0.1 second) that works the mischief; When short circuit current during less than operating current, certainly will be because of the delay of time, short trouble will initiation fire or other accidents.
The patent No. is to disclose a kind of DC system short circuit protection device for the patent of invention of CN1323476C ZL02126652.2, Granted publication number; this protective device is made of parts such as comprising data acquisition circuit, change-over circuit and industrial computer; its operation principle satisfies the tributary branch current greater than short trouble identification electric current and DC bus-bar voltage during less than short trouble identification voltage simultaneously for adopting; the sign that breaks down as direct current system, thus be defeated by breaker protection tripping operation control circuit through the relay output circuit sending control signal through the selectivity criterion.This circuit adopts short circuit current and voltage simultaneously as the signal of judging short circuit; exist equally because the big short circuit current of single-phase short circuit impedance loop is less; can not when taking place, short trouble realize giving the defective of tripping operation control circuit output short-circuit signal in the short-circuit protection synchronously.The short-circuit protection that comprises other in addition; the extremely complicated electronic devices and components of many employings constitute various functional entities and constitute; and the useful life of electronic device is limited, and the circuit complex fault rate height of forming, and therefore exists short defective of complex structure, useful life.
The utility model content
The technical problems to be solved in the utility model provides and a kind ofly can play reliably protecting effect, shunted exciter tripping type single-phase short circuit protecting equipment simple in structure to the single-phase 220V electric network terminal load equipment that spreads all over town and country and circuit.
For addressing the above problem, the technical solution adopted in the utility model is:
A kind of shunted exciter tripping type single-phase short circuit protecting equipment comprises the short switch actuator that is made of the mechanical lock buckle that is connected with spring of controlling the single-phase short circuit switch;
An end of controlling the shunt opening trip coil of described mechanical lock buckle is connected with protective earthing line (PEE) or protective wire (PES), the other end is connected to form the startup loop by the normally opened contact and the described neutral line wiring point of electromagnetic relay, constitutes short switch action launching mechanism;
The two ends that described electromagnetic relay is connected in parallel in the normally opened contact of described shunt opening trip coil and electromagnetic relay form detection triggering loop, constitute the short-circuit detecting trigger mechanism.
Its additional technical feature is:
Be in series with electric capacity in the startup loop that constitutes by the normally opened contact of described shunt opening trip coil and described electromagnetic relay;
Be in series with divider resistance in the startup loop that constitutes by the normally opened contact of described shunt opening trip coil and described electromagnetic relay;
Described detection triggers the loop and is in series with regulating resistor;
Described neutral line tie point and described detection trigger between loop and described startup loop and are in series with rectification mechanism;
Described detection triggers in the loop and is serially connected with rectification mechanism.
A kind of shunted exciter tripping type single-phase short circuit protecting equipment provided by the utility model compared with prior art has the following advantages:
In this single-phase short circuit protective device, be provided with the detection trigger mechanism; detect direct current or ac voltage signal or current signal between the neutral line (N) and protective earthing line (PEE) or protective wire (PES) when the parameter of its detection adopts short circuit, and the size of this direct current or ac voltage signal or current signal and short-circuit current value is irrelevant.When the signal of this detection reaches about definite value, detect trigger mechanism and send instruction to actuating mechanism, make the normally opened contact closure of electromagnetic relay; Actuating mechanism sends instruction to short circuit actuator, and actuator disconnects short switch, thereby realizes the function to the single-phase short circuit protection.
In this single-phase short circuit protective device, be provided with action actuating mechanism, solved existing single-phase short circuit protective device when short circuit current tripping problem during less than its at the appointed time operating current.It is the different shunt trip of electromagnetic force trip gear that produces with the short circuit current of current-release type.The electric current (direct current or interchange) that flows through shunt opening trip coil is large and small irrelevant with short circuit current.No matter it the short circuit current size, all can greatly improve the reliability of tripping coil action on request.
In this protective device, be provided with the action actuating mechanism power sector.When it has solved single-phase short circuit, phase line and neutral line equipotential, the former shunt opening trip coil two ends that are connected on phase line and the neutrality do not have pressure, and akinesia can not be protected single-phase short circuit cut-out accident circuit and the difficult problem of initiation fire.It is with under the single-phase short circuit state, and the voltage (exchanging or direct current) between the neutral line and protective wire ground connection (PEE) or the protective wire (PES) offers shunt opening trip coil by the requirement of action reliability.Solved the technical barrier that single-phase short circuit can not shunted exciter tripping.
This device can be widely used in the single-phase user of terminal and the phase line of three-phase and four-line downlead place circuit breaker in the scope that protective wire and the neutral line separate in TT system, TN-S system and the TN-C-S system of power supply neutral-point solid ground, the automatic protection of neutral line short circuit.
Description of drawings
Fig. 1: be the circuit interconnect pattern of single-phase short circuit protective device in the prior art;
Fig. 2 a: be the circuit interconnect pattern of shunted exciter tripping type single-phase short circuit protecting equipment;
Fig. 2 b: be the circuit theory diagrams of Fig. 2 a;
Fig. 3 a: be second kind of shunted exciter tripping type single-phase short circuit firebreak device circuit interconnect pattern;
Fig. 3 b: be the circuit theory diagrams of Fig. 3 a;
Fig. 4 a: be the third shunted exciter tripping type single-phase short circuit firebreak device circuit interconnect pattern;
Fig. 4 b: be the circuit theory diagrams of Fig. 4 a;
Fig. 5: for being used in the three-phase five-wire mode elementary diagram in the low voltage electric network.
Embodiment
Be described in further detail below in conjunction with the structure and the circuit theory of accompanying drawing shunted exciter tripping type single-phase short circuit protecting equipment provided by the utility model.
Shown in Fig. 2 a and the 2b, be the circuit interconnect pattern and the circuit theory diagrams of shunted exciter tripping type single-phase short circuit protecting equipment provided by the utility model.This shunted exciter tripping type single-phase short circuit protecting equipment comprises: the short switch action actuating mechanism that is made of the mechanical lock buckle 1 that is used to control short switch k and be connected with spring 2; Be connected in the detection triggering loop that the electromagnetic relay DJ between neutral line N wiring point 3 and protective earthing line PEE (or protective wire PES) constitutes; The shunt opening trip coil TQ of control mechanical lock buckle 1 is connected the back and constitutes short switch startup loop with protective earthing line PEE (or protective wire PES) with electromagnetic relay normally opened contact DJK.
Its operation principle is:
When single-phase electrical network is normal, when the neutral line N of 4 sides of promptly loading and live wire L are not short-circuited, the voltage drop of the detection trigger mechanism that is made of electromagnetic relay DJ is very low, voltage drop when its value is passed through electric current for the neutral line is+7% He by " low-voltage power technical regulation " 220V line voltage permissible variation--10%, require three-phase load unbalance factor 25% simultaneously, promptly neutral current should be greater than 1/4 of phase line average current.So the neutral line is over the ground about (protective earthing line PEE, protective wire PES) voltage=220V * 10% ÷, 2 * 1/4=3V.It is very little that current in loop is touched in detection this moment, detects triggering element electromagnetic relay DJ and be equivalent to an impedance, do not influence the normal operation of electrical network.Voltage about this 3V is enough to make electromagnetic relay DJ to trigger its normally opened contact DJK closure far from, therefore can not make the startup circuit communication, and actuator just can not move yet short switch is disconnected.
When the short switch load side was short-circuited, then voltage will be far longer than about just often 3V between neutral line N and protective earthing line PEE (or protective wire PES)---when short circuit current is 2 times of transformer secondary rated current, and the power end voltage U
2=230 * (1-U * 2)=210V, short dot neutral line N is to protective earthing line PEE (or protective wire PES) voltage U
NE=110V press dry, props up a line segment neutral line cross section because of hanging down and is less than phase line, and the voltage drop of the neutral line is bigger.At this moment, detect the voltage that triggers the loop and can reach 110V, if setting the operation voltage of electromagnetic relay DJ is 80V, then electromagnetic relay DJ action makes its normally opened contact DJK closure, start circuit communication, the electromagnetic force that shunt opening trip coil TQ produces is opened mechanical lock buckle 1, and the work of short switch actuator disconnects the purpose that short switch reaches electric power disconnection.When the operation voltage of setting electromagnetic relay DJ is 80V, detect the safety factor K that triggers
f=110/80=1.4.
In order to adjust the safety factor that detects trigger mechanism, the divider resistance R1 that in detecting the triggering loop, connects, this divider resistance R1 is used for adjustment and detects current in loop.When this resistance was big more, current in loop was just more little, and the voltage drop of electromagnetic relay DJ is just more little, and sensitivity reduces; Otherwise it is high more.
As shown in Figure 5, the three-phase five-wire mode elementary diagram for generally using in the 220/380V low voltage electric network.Respectively be connected with power consumption equipment W1, W2 and W3 on three phase line L1, L2 in the figure and L3 and the neutral line N.For fear of working as shared protective wire PES because power consumption equipment W1; the power consumption equipment of one of them among W2 or the W3 is owing to electric leakage causes power consumption equipment W1; the outer casing electrification of W2 or W3; when because when the malfunctioning tripping of earth leakage circuit-breaker of power consumption equipment of leak current fault takes place (when also causing residual current protecting not move); the current potential at the shared protective wire PES of the power consumption equipment place of fault will not be higher than the current potential of neutral line N owing to be short-circuited; the two forms voltage will cause that electromagnetic relay DJ triggers its normally opened contact DJK closure among Fig. 2 a; thereby cause actuator that malfunction takes place; promptly cause the short switch of the power consumption equipment of this fault that is not short-circuited to disconnect, its operate as normal is exerted an influence.Then
---the circuit of the shunted exciter tripping type single-phase short circuit protecting equipment of employing shown in Fig. 3 a and 3b can be avoided the generation of above-mentioned phenomenon.Promptly connecting in the detection circuits for triggering that constitute the single-phase short circuit protective device has the diode D of rectification function, makes the detection circuits for triggering change dc detection circuit into.Even when the current potential of shared protective wire PES is higher than the current potential generation voltage of neutral line N,, make the electromagnetic relay DJ that detects trigger mechanism can not send triggering signal as actuating mechanism because the effect of diode D does not have electric current yet and passes through among the electromagnetic relay DJ.The power consumption equipment that promptly can avoid not being short-circuited causes its short switch to disconnect the generation of phenomenon because of other power consumption equipment electric leakages.In foregoing circuit, the effect of series capacitance C in the startup loop that shunt opening trip coil TQ constitutes is to be used to adjust the impedance that starts the loop.The i.e. impedance in this loop is more little, and the startup sensitivity of shunt opening trip coil TQ is just high more.
---adopt the circuit of shunted exciter tripping type single-phase short circuit protecting equipment as shown in Figs. 4a and 4b, promptly between neutral line wiring point 3 and detection triggering loop and startup loop, be in series with the generation that the diode D with rectification function equally also can avoid above-mentioned phenomenon.The divider resistance R2 that is connected in series in this startup loop circuit is used to adjust the impedance that starts the loop.The impedance in same this loop is more little, and the startup of shunt opening trip coil TQ is sensitive just high more.
Shunted exciter tripping type single-phase short circuit protecting equipment provided by the utility model not only has the function of single-phase short circuit protection, also has the function that the power consumption equipment that is connected is had overvoltage protection:
Be illustrated in figure 5 as and be connected in not single-phase electric devices W1, the W2 between isopen L1, L2 and L3 and neutral line N and the electrical schematic diagram of W3.
---in this circuit, when opening circuit as public neutral line N, then the power consumption equipment between isopen does not become and is being connected in series between voltage 380V phase voltage, and when the impedance unbalance of two power consumption equipments that are connected in series, can cause the big power consumption equipment of impedance to damage or the phenomenon that is short-circuited because of overvoltage, can produce chain reaction thus, overvoltage also can take place thereupon and damage short circuit in other power consumption equipments of polyphone, and whole electrical network is produced influence greatly.Such as; shunted exciter tripping type single-phase short circuit protecting equipment K provided by the utility model is connected among the above-mentioned power consumption equipment W1; after when open circuit fault takes place in public neutral line N; power consumption equipment W1 and W2 have just become the series relationship between phase line L1 and the L2; when power consumption equipment W1 and the serious imbalance of W2, the voltage at its two ends has become the line voltage that approaches 380V by the phase voltage of 220V.When the serious imbalance of the load of power consumption equipment W1 and W2 causes neutral point displacement; when neutral line voltage (N is to PEE, PES) equals greater than 80V; detect the normally opened contact DJK closure of the solenoid DJ of trigger mechanism; in time start circuit communication; in time the shunt opening trip coil in the actuating mechanism starts; make short switch K disconnect action, exempt from the overvoltage infringement with protection load side power consumption equipment, electrical equipment.
---in this circuit, when the circuit of the power consumption equipment on the phase line was short-circuited fault, the line voltage rising as public neutral line N caused the overvoltage of the power consumption equipment on other phase lines to burn easily.Such as; shunted exciter tripping type single-phase short circuit protecting equipment K provided by the utility model is connected among the above-mentioned power consumption equipment W1; after when the phase line L2 of power consumption equipment W2 and public neutral line N are short-circuited fault; current potential on the public neutral line N will increase; and and to forming voltage between PEE, PES; trigger single-phase short circuit protective device K action and disconnect short switch, the power consumption equipment W1 of protection switch load side is unlikely to overvoltage and burns.
Claims (6)
1, a kind of shunted exciter tripping type single-phase short circuit protecting equipment comprises the short switch actuator that is made of the mechanical lock buckle that is connected with spring of controlling the single-phase short circuit switch; Control the shunt opening trip coil of described mechanical lock buckle, it is characterized in that:
One end of described shunt opening trip coil is connected with protective earthing line (PEE) or protective wire (PES), and the other end is connected to form the startup loop by the normally opened contact and the described neutral line wiring point of electromagnetic relay, constitutes short switch action launching mechanism;
The two ends that described electromagnetic relay is connected in parallel in the normally opened contact of described shunt opening trip coil and electromagnetic relay form detection triggering loop, constitute the short-circuit detecting trigger mechanism.
2, a kind of shunted exciter tripping type single-phase short circuit protecting equipment as claimed in claim 1 is characterized in that: be in series with electric capacity in the startup loop that is made of the normally opened contact of described shunt opening trip coil and described electromagnetic relay.
3, a kind of shunted exciter tripping type single-phase short circuit protecting equipment as claimed in claim 1 is characterized in that: be in series with divider resistance in the startup loop that is made of the normally opened contact of described shunt opening trip coil and described electromagnetic relay.
4, a kind of shunted exciter tripping type single-phase short circuit protecting equipment as claimed in claim 1 is characterized in that: described detection triggers the loop and is in series with regulating resistor.
5, a kind of shunted exciter tripping type single-phase short circuit protecting equipment as claimed in claim 1 is characterized in that: described neutral line wiring point and described detection trigger between loop and described startup loop and are in series with rectification mechanism.
6, a kind of shunted exciter tripping type single-phase short circuit protecting equipment as claimed in claim 1 is characterized in that: described detection triggers in the loop and is serially connected with rectification mechanism.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2008100544698A CN100546142C (en) | 2008-01-29 | 2008-01-29 | A kind of shunted exciter tripping type single-phase short circuit protecting equipment |
| CNU2008200762128U CN201146366Y (en) | 2008-01-29 | 2008-01-29 | Shunt-opening tripping type equipment for protecting single-phase short circuit |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2008100544698A CN100546142C (en) | 2008-01-29 | 2008-01-29 | A kind of shunted exciter tripping type single-phase short circuit protecting equipment |
| CNU2008200762128U CN201146366Y (en) | 2008-01-29 | 2008-01-29 | Shunt-opening tripping type equipment for protecting single-phase short circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN201146366Y true CN201146366Y (en) | 2008-11-05 |
Family
ID=72474045
Family Applications (2)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNU2008200762128U Expired - Lifetime CN201146366Y (en) | 2008-01-29 | 2008-01-29 | Shunt-opening tripping type equipment for protecting single-phase short circuit |
| CNB2008100544698A Expired - Fee Related CN100546142C (en) | 2008-01-29 | 2008-01-29 | A kind of shunted exciter tripping type single-phase short circuit protecting equipment |
Family Applications After (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB2008100544698A Expired - Fee Related CN100546142C (en) | 2008-01-29 | 2008-01-29 | A kind of shunted exciter tripping type single-phase short circuit protecting equipment |
Country Status (1)
| Country | Link |
|---|---|
| CN (2) | CN201146366Y (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102545147A (en) * | 2012-02-16 | 2012-07-04 | 常州工学院 | Method for tandem operation of alternating current shunt release and alternating current relay |
| CN102543604A (en) * | 2012-02-16 | 2012-07-04 | 常州工学院 | Direct current shunt release applicable to operation in series connection with direct current relay |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101350514B (en) * | 2008-08-25 | 2010-04-21 | 常立柱 | Current-limiting arc-extinguishing shunted exciter tripping type earthing short circuit protection device |
| CN101944734A (en) * | 2009-07-06 | 2011-01-12 | 孙巍巍 | Novel surge protector |
| EP3061130B1 (en) | 2013-12-17 | 2020-11-04 | Siemens Aktiengesellschaft | A protective electronic module for an hvdc convertor |
| CN107225993B (en) * | 2017-07-08 | 2023-08-15 | 山东九路泊车设备股份有限公司 | Continuous safe charging system of vertical circulation stereo garage |
| EP3985708A1 (en) * | 2020-10-16 | 2022-04-20 | ABB Schweiz AG | Current breaker device |
-
2008
- 2008-01-29 CN CNU2008200762128U patent/CN201146366Y/en not_active Expired - Lifetime
- 2008-01-29 CN CNB2008100544698A patent/CN100546142C/en not_active Expired - Fee Related
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102545147A (en) * | 2012-02-16 | 2012-07-04 | 常州工学院 | Method for tandem operation of alternating current shunt release and alternating current relay |
| CN102543604A (en) * | 2012-02-16 | 2012-07-04 | 常州工学院 | Direct current shunt release applicable to operation in series connection with direct current relay |
| CN102543604B (en) * | 2012-02-16 | 2014-04-09 | 常州工学院 | Direct current shunt release applicable to operation in series connection with direct current relay |
| CN102545147B (en) * | 2012-02-16 | 2014-04-09 | 常州工学院 | Method for tandem operation of alternating current shunt release and alternating current relay |
Also Published As
| Publication number | Publication date |
|---|---|
| CN100546142C (en) | 2009-09-30 |
| CN101232169A (en) | 2008-07-30 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| AV01 | Patent right actively abandoned |
Effective date of abandoning: 20080129 |
|
| C25 | Abandonment of patent right or utility model to avoid double patenting |