CN102751694A - Device and method for controlling neutral wire breaking protection - Google Patents
Device and method for controlling neutral wire breaking protection Download PDFInfo
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- CN102751694A CN102751694A CN2011100576188A CN201110057618A CN102751694A CN 102751694 A CN102751694 A CN 102751694A CN 2011100576188 A CN2011100576188 A CN 2011100576188A CN 201110057618 A CN201110057618 A CN 201110057618A CN 102751694 A CN102751694 A CN 102751694A
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Abstract
The invention discloses a device and a method for controlling neutral wire breaking protection. The device comprises a main controller, a power supply circuit connected with the main controller, a sampling filter circuit, a fault indication circuit, and a driving execution circuit. The power supply circuit comprises a capacitance-resistance pressure relief unit, a power management unit, and a voltage stabilization unit connected in sequence. The sampling filter circuit comprises three first branch circuits, the first branch circuit comprising a sampling unit, a rectifying unit and a filtering unit connected in sequence. The fault indication circuit comprises two parallel second branch circuits, and the second branch circuit is formed by a resistance and a light-emitting diode connected in series. The driving execution circuit comprises an audion and a relay, and the audion and the relay cooperate with each other to perform breakover on an electrical line. Based on the above device, the invention also discloses a method for controlling the neutral wire breaking protection. The device and the method can control a circuit breaker tripping after a neutral wire is broken, cut off a power side circuit, and protect electric equipment safety and personal safety in a three-phase four-wire system power-supply system.
Description
Technical field
The present invention relates to the neutral line protection field of three phase and four wire circuit system, particularly relate to a kind of broken neutral line protection control device and method.
Background technology
In the three phase and four wire circuit system, the neutral line is the common return of three-phase circuit.The neutral line can guarantee that threephase load becomes three independent loops that are independent of each other; No matter whether each phase load balance, each phase load all can bear the phase voltage of symmetry, no matter promptly which breaks down mutually, other two mutually can both operate as normal.But, threephase load is in when moving under the asymmetric situation, in case neutral line generation disconnection fault then can cause break point neutral line potential shift U afterwards
NN, U when serious
NNEven, making each phase load Voltage unbalance greater than 50V, corresponding with it threephase load phase voltage is crossed, the under voltage value will reach more than 20% of rated value, causes power consumption equipment to burn or cisco unity malfunction.Simultaneously, be the electrical system of TN-C or TN-C-S as far as earthing mode, because the current potential of neutral point improves, make through voltage dangerous on protective earthing-neutral conductor or PE line and the joining shell band of electric equipment, directly jeopardize personal safety.
According to stipulating in China's " civil buildings electrical design standard ": when the neutral line generation disconnection fault in the three-phase four-wire system distribution line, need to cut off automatically the whole power circuits of load side.Regulation in the national standard " low-voltage distribution design specification ": in the mode of connection is in the electrical system of TN-C or TN-C-S, forbids to break off the neutral line (protective earthing-neutral conductor), in case neutral line generation disconnection fault in time breaks off distribution line.
In sum, for safety and the personal safety that ensures power consumption equipment in the three phase and four wire circuit system, of crucial importance to the protection of the three phase and four wire circuit system neutral line.
Summary of the invention
The objective of the invention is in order to overcome the deficiency of above-mentioned background technology; A kind of broken neutral line protection control device and method are provided; Circuit breaker trip can behind broken neutral line, be controlled, the side line road of cutting off the electricity supply, the safety and the personal safety of power consumption equipment in the protection three phase and four wire circuit system.
Broken neutral line protection control device provided by the invention; Comprise master controller and the power-supplying circuit that links to each other with said master controller; Also comprise the sampling filter circuit, failure indicating circuit and the driving execution circuit that link to each other with said master controller respectively, said power-supplying circuit comprises resistance-capacitance depressurization power supply, PMU and the voltage regulation unit that links to each other successively; Said sampling filter circuit comprises three first branch roads, and said first branch road comprises sampling unit, rectification unit and the filter unit that links to each other successively; Said failure indicating circuit comprises second branch road of two parallel connections, and said second route resistance becomes with the light-emitting diode series; Said driving execution circuit comprises triode and the relay that cooperatively interacts and be used for the conducting electric loop.
In technique scheme, also comprise with the power end of said master controller the power reset circuit that links to each other, is used to monitor the power supply status fluctuation, said power reset circuit comprises the power reset chip.
In technique scheme; Said power-supplying circuit links to each other with the power end of master controller; The sampling filter circuit links to each other with the analog signal input channel of master controller, and failure indicating circuit links to each other with the I/O mouth of master controller, and the driving execution circuit links to each other with the relay control end of master controller.
In technique scheme, said master controller comprises three analog signal input channels, corresponding respectively three first branch roads that connect said sampling filter circuit of said three analog signal input channels.
In technique scheme, the resistance-capacitance depressurization power supply in the said power-supplying circuit comprises pressure unit, and said pressure unit comprises the bleeder resistance and the current limliting dividing potential drop electric capacity of parallel connection.
In technique scheme, resistance one end in every second branch road of said failure indicating circuit links to each other with the I/O mouth of master controller, and the other end links to each other the minus earth of said light-emitting diode with the light-emitting diode in this branch road is anodal.
In technique scheme; The base stage of triode inserts the relay control end of master controller in the said driving execution circuit through a resistance; The collector electrode of triode connects coil one end of said relay, and the grounded emitter of triode also is connected with electric capacity between the base stage of triode and the emitter; Another termination power of the coil of said relay, said relay two ends are parallel with diode.
On the hardware foundation of using above-mentioned broken neutral line protection control device, the present invention also provides a kind of broken neutral line protection control method, may further comprise the steps:
Behind A, the system initialization, give the house dog input signal;
B, judgement have been arrived electrical network during the cycle, give the house dog input signal, and the calculating voltage effective value; Otherwise forward steps A to;
C, judge when satisfying the null offset fault, forward step D to; Otherwise remove the circuit breaker trip signal, the control fault indicator light extinguishes, normal condition indicator light Chang Liang, forwards steps A again to;
D, judge and to have delayed time three seconds the time that control circuit breaker trip, normal condition indicator light extinguish; Otherwise forward steps A to;
E, judge and to have delayed time one second the time flicker of control fault indicator light; Otherwise forward steps A to.
In technique scheme, system initialization may further comprise the steps successively described in the steps A: close house dog, forbid regularly interrupting; The external clock initialization, outside port initialization, analog-to-digital conversion initialization; The timer initialization allows regularly to interrupt, and opens house dog.
In technique scheme, said timing is interrupted may further comprise the steps successively: get into regularly and interrupt; Read voltage-mode number conversion value; The sampled value middle position value filtering; The signal that calculates second analog signal input channel add up with; Processes voltage periodic signal amount.
The invention has the advantages that: can behind broken neutral line, control circuit breaker trip, the side line road of cutting off the electricity supply, the safety and the personal safety of power consumption equipment in the protection three phase and four wire circuit system.
Description of drawings
Fig. 1 is the structured flowchart of embodiment of the invention broken neutral line protection control device;
Fig. 2 is the circuit diagram of embodiment of the invention broken neutral line protection control device;
Fig. 3 is the circuit diagram of embodiment of the invention power-supplying circuit;
Fig. 4 is the circuit diagram of embodiment of the invention sampling filter circuit;
Fig. 5 is the circuit diagram of embodiment of the invention power reset circuit;
Fig. 6 is the circuit diagram of embodiment of the invention failure indicating circuit;
Fig. 7 is the circuit diagram of embodiment of the invention driving execution circuit;
Fig. 8 is the flow chart of embodiment of the invention broken neutral line protection control method;
The flow chart that Fig. 9 regularly interrupts for the embodiment of the invention.
Embodiment
Below in conjunction with accompanying drawing and embodiment the present invention is made further detailed description:
Referring to shown in Figure 1; The broken neutral line protection control device that the embodiment of the invention provides comprises master controller and the power-supplying circuit that links to each other with master controller respectively, sampling filter circuit, power reset circuit, failure indicating circuit and driving execution circuit, wherein; Power-supplying circuit links to each other with the power end of master controller; The sampling filter circuit links to each other with the analog signal input channel of master controller, and power reset circuit links to each other with the power end of master controller, is used to monitor the fluctuation of power supply status; Failure indicating circuit links to each other with the I/O mouth of master controller, and the driving execution circuit links to each other with the relay control end of master controller.
Referring to shown in Figure 2, power-supplying circuit comprises resistance-capacitance depressurization power supply, PMU and the voltage regulation unit that links to each other successively, and the resistance-capacitance depressurization power supply comprises pressure unit, and pressure unit comprises the bleeder resistance and the current limliting dividing potential drop electric capacity of parallel connection.The sampling filter circuit comprises three first branch roads, and said first branch road comprises sampling unit, rectification unit and the filter unit that links to each other successively, three first corresponding respectively three analog signal input channel AD1, AD2 and the AD3 that connect master controller of branch road.Power reset circuit comprises the power reset chip,, it is a timer, is specifically designed to the running status of monitoring facilities, can prevent that program generation endless loop from preventing program fleet in other words.Failure indicating circuit comprises second branch road of two parallel connections; Said second route resistance becomes with the light-emitting diode series; Resistance one end in every second branch road links to each other with the I/O mouth of master controller, and the other end links to each other the minus earth of light-emitting diode with the light-emitting diode in this branch road is anodal.The driving execution circuit comprises triode Q2 and the relay that cooperatively interacts and be used for the conducting electric loop; Wherein, the base stage of triode Q2 is through the relay control end of resistance access master controller, and the collector electrode of triode Q2 connects coil one end of said relay; The grounded emitter of triode Q2; Also be connected with capacitor C 11 between the base stage of triode Q2 and the emitter, another termination power of the coil of relay, the relay two ends are parallel with diode D7.
Referring to shown in Figure 3, power-supplying circuit is supplied power to whole system, adopts the design of resistance-capacitance depressurization power supply, and pressure unit adopts resistance R 18 and capacitor C 9 parallel connections to carry out step-down.Resistance R 18 is a bleeder resistance, and its resistance is 510k, remaining electric charge on the electric capacity that is used to release.Capacitor C 9 utilizes the capacitive reactance current limliting to carry out step-down, and its concrete parameter is 2.2uF/630V, in fact plays the effect of restriction electric current and dynamic assignment electric capacity and load voltage.PMU is stabilized in 5V and 3.3V to voltage through power management chip AMS1117-5 and AMS1117-3.3, to whole system power supply is provided.Voltage regulation unit is stabilized in 6.2 volts through zener diode D9 with its voltage.
Referring to shown in Figure 4, the sampling filter circuit is sampled through resistance R 1, R2 dividing potential drop earlier, carries out halfwave rectifier through diode D1 again, at this moment line voltage U
oWith sampled voltage U
iSatisfy following relation:
Through amplifier U1A sampled signal is carried out low-pass filtering treatment then, cut-off frequency is:
Wherein, ω
0Be cut-off angular frequency, R=10k Ω, C1=0.01uF, C2=0.047uF.
Referring to shown in Figure 5, power reset circuit passes through power reset chip monitoring power supply state, when the operating voltage of master controller is lower than 2.93V, and system's cisco unity malfunction, main controller controls system reset.
Referring to shown in Figure 6, failure indicating circuit is used for the operating state of indication mechanism.When the neutral line disconnection fault do not occur, green indicating lamp Chang Liang, indication mechanism is in normal operating conditions; After disconnection fault appears in the neutral line, the red led flicker, indication mechanism breaks down.
Referring to shown in Figure 7, the driving execution circuit is the control operating part of system, when disconnection fault appears in the neutral line; Master controller time-delay three seconds, control triode Q2 conducting, the coil of driving 5V relay; This coil get electric after, the normally opened contact of control relay is closed, connects electric loop after the normally opened contact closure; Release gets the action of electric back, makes circuit breaker trip.
On the hardware foundation of using above-mentioned broken neutral line protection control device, the present invention also provides a kind of broken neutral line protection control method, may further comprise the steps:
A, system initialization: close house dog, forbid regularly interrupting, the external clock initialization, the outside port initialization, the analog-to-digital conversion initialization, the timer initialization allows regularly to interrupt, and opens house dog; Regularly interrupt comprising successively step: get into regularly and interrupt; Read voltage-mode number conversion value; The sampled value middle position value filtering; The signal that calculates second analog signal input channel add up with; Processes voltage periodic signal amount; Behind the system initialization, give the house dog input signal;
B, judgement have been arrived electrical network during the cycle, give the house dog input signal, and the calculating voltage effective value; Otherwise forward steps A to;
C, judge when satisfying the null offset fault, forward step D to; Otherwise remove the circuit breaker trip signal, the control fault indicator light extinguishes, normal condition indicator light Chang Liang, forwards steps A again to;
D, judge and to have delayed time three seconds the time that control circuit breaker trip, normal condition indicator light extinguish; Otherwise forward steps A to;
E, judge and to have delayed time one second the time flicker of control fault indicator light; Otherwise forward steps A to.
Referring to shown in Figure 8, the broken neutral line protection control method that the embodiment of the invention provides specifically may further comprise the steps:
Step 101: program begins;
Step 102: system initialization comprises successively: closes house dog, forbids regularly interrupting, and the external clock initialization, the outside port initialization, the analog-to-digital conversion initialization, the timer initialization allows regularly to interrupt, and opens house dog;
Step 103: give house dog input signal (cry again and feed dog);
Step 104: judge whether the electrical network cycle arrive, if then forward step 105 to; Otherwise, forward step 103 to;
Step 105: give the house dog input signal;
Step 106: calculating voltage effective value;
Step 107: judge whether to satisfy the null offset fault, if then forward step 109 to; Otherwise, forward step 108 to;
Step 108: remove the circuit breaker trip signal, the control red led extinguishes, green indicating lamp Chang Liang, forwards step 103 again to;
Step 109: judged whether to delay time three seconds, if then forward step 110 to; Otherwise, forward step 103 to;
Step 110: control circuit breaker trip, green indicating lamp extinguish;
Step 111: judged whether to delay time one second, if then forward step 112 to; Otherwise, forward step 103 to;
Step 112: control red led flicker.
Referring to shown in Figure 9, regularly interrupt specifically may further comprise the steps:
Step 201: get into regularly and interrupt;
Step 202: read voltage AD conversion value;
Step 203: sampled value middle position value filtering;
Step 204: calculate AD2 add up with;
Step 205: processes voltage periodic signal amount.
Obviously, those skilled in the art can carry out various changes and modification to the present invention and not break away from the spirit and scope of the present invention.Like this, belong within the scope of claim of the present invention and equivalent technologies thereof if of the present invention these are revised with modification, then the present invention also is intended to comprise these changes and modification interior.
The content of not doing in this specification to describe in detail belongs to this area professional and technical personnel's known prior art.
Claims (10)
1. a broken neutral line is protected control device; Comprise master controller and the peripheral circuit that links to each other with said master controller; It is characterized in that: also comprise the sampling filter circuit, failure indicating circuit and the driving execution circuit that link to each other with said master controller respectively, said power-supplying circuit comprises resistance-capacitance depressurization unit, PMU and the voltage regulation unit that links to each other successively; Said sampling filter circuit comprises three first branch roads, and said first branch road comprises sampling unit, rectification unit and the filter unit that links to each other successively; Said failure indicating circuit comprises second branch road of two parallel connections, and said second route resistance becomes with the light-emitting diode series; Said driving execution circuit comprises triode and the relay that cooperatively interacts and be used for the conducting electric loop.
2. broken neutral line protection control device as claimed in claim 1 is characterized in that: also comprise the fluctuation status that links to each other, is used to monitor power supply with the power end of said master controller.
3. broken neutral line protection control device as claimed in claim 1; It is characterized in that: said power-supplying circuit links to each other with the power end of master controller; The sampling filter circuit links to each other with the analog signal input channel of master controller; Failure indicating circuit links to each other with the I/O mouth of master controller, and the driving execution circuit links to each other with the relay control end of master controller.
4. broken neutral line protection control device as claimed in claim 3, it is characterized in that: said master controller comprises three analog signal input channels, corresponding respectively three first branch roads that connect said sampling filter circuit of said three analog signal input channels.
5. broken neutral line protection control device as claimed in claim 1, it is characterized in that: the resistance-capacitance depressurization power supply in the said power-supplying circuit comprises pressure unit, said pressure unit comprises the bleeder resistance and the current limliting dividing potential drop electric capacity of parallel connection.
6. broken neutral line protection control device as claimed in claim 1; It is characterized in that: resistance one end in every second branch road of said failure indicating circuit links to each other with the I/O mouth of master controller; The other end links to each other the minus earth of said light-emitting diode with the light-emitting diode in this branch road is anodal.
7. like the described broken neutral line protection of each claim of claim 1 to 6 control device; It is characterized in that: the base stage of triode inserts the relay control end of master controller in the said driving execution circuit through a resistance; The collector electrode of triode connects coil one end of said relay, and the grounded emitter of triode also is connected with electric capacity between the base stage of triode and the emitter; Another termination power of the coil of said relay, said relay two ends are parallel with diode.
8. use the broken neutral line protection control method of broken neutral line protection control device as claimed in claim 1, it is characterized in that may further comprise the steps:
Behind A, the system initialization, give the house dog input signal;
B, judgement have been arrived electrical network during the cycle, give the house dog input signal, and the calculating voltage effective value; Otherwise forward steps A to;
C, judge when satisfying the null offset fault, forward step D to; Otherwise remove the circuit breaker trip signal, the control fault indicator light extinguishes, normal condition indicator light Chang Liang, forwards steps A again to;
D, judge and to have delayed time three seconds the time that control circuit breaker trip, normal condition indicator light extinguish; Otherwise forward steps A to;
E, judge and to have delayed time one second the time flicker of control fault indicator light; Otherwise forward steps A to.
9. broken neutral line protection control method as claimed in claim 8, it is characterized in that: system initialization may further comprise the steps successively described in the steps A: close house dog, forbid regularly interrupting; The external clock initialization; The outside port initialization, analog-to-digital conversion initialization, timer initialization; Allow regularly to interrupt, open house dog.
10. broken neutral line protection control method as claimed in claim 9, it is characterized in that: said timing is interrupted may further comprise the steps successively: get into regularly and interrupt; Read voltage-mode number conversion value; The sampled value middle position value filtering; The signal that calculates second analog signal input channel add up with; Processes voltage periodic signal amount.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011100576188A CN102751694A (en) | 2011-04-22 | 2011-04-22 | Device and method for controlling neutral wire breaking protection |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011100576188A CN102751694A (en) | 2011-04-22 | 2011-04-22 | Device and method for controlling neutral wire breaking protection |
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| CN102751694A true CN102751694A (en) | 2012-10-24 |
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| CN2011100576188A Pending CN102751694A (en) | 2011-04-22 | 2011-04-22 | Device and method for controlling neutral wire breaking protection |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104124664A (en) * | 2014-08-19 | 2014-10-29 | 国网浙江宁波市鄞州区供电公司 | Line breakage protection method and line breakage protection system for neutral line |
| CN109073263A (en) * | 2016-05-13 | 2018-12-21 | 三菱电机株式会社 | Air conditioner |
| CN110676824A (en) * | 2019-11-28 | 2020-01-10 | 国网江苏省电力有限公司镇江供电分公司 | 110kV line disconnection protection method for collecting bus voltage of line load end |
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| CN1298219A (en) * | 2000-09-19 | 2001-06-06 | 薛小平 | Intelligent uniphase voltage deviation protector |
| CN2727847Y (en) * | 2004-06-09 | 2005-09-21 | 李世学 | Intelligent power supplying and electricity stolen proofing network management system |
| CN1728492A (en) * | 2004-07-27 | 2006-02-01 | 乌鲁木齐市神安实业有限公司 | Protector for imbalance of three-phase voltage |
| CN1744403A (en) * | 2004-09-02 | 2006-03-08 | 薛小平 | Intelligent magnetic retaining over under voltage protector |
| CN201490686U (en) * | 2009-07-11 | 2010-05-26 | 杭州之江开关股份有限公司 | Self-recover overvoltage-undervoltage protector |
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Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN1298219A (en) * | 2000-09-19 | 2001-06-06 | 薛小平 | Intelligent uniphase voltage deviation protector |
| CN2727847Y (en) * | 2004-06-09 | 2005-09-21 | 李世学 | Intelligent power supplying and electricity stolen proofing network management system |
| CN1728492A (en) * | 2004-07-27 | 2006-02-01 | 乌鲁木齐市神安实业有限公司 | Protector for imbalance of three-phase voltage |
| CN1744403A (en) * | 2004-09-02 | 2006-03-08 | 薛小平 | Intelligent magnetic retaining over under voltage protector |
| CN201490686U (en) * | 2009-07-11 | 2010-05-26 | 杭州之江开关股份有限公司 | Self-recover overvoltage-undervoltage protector |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104124664A (en) * | 2014-08-19 | 2014-10-29 | 国网浙江宁波市鄞州区供电公司 | Line breakage protection method and line breakage protection system for neutral line |
| CN109073263A (en) * | 2016-05-13 | 2018-12-21 | 三菱电机株式会社 | Air conditioner |
| CN110676824A (en) * | 2019-11-28 | 2020-01-10 | 国网江苏省电力有限公司镇江供电分公司 | 110kV line disconnection protection method for collecting bus voltage of line load end |
| CN110676824B (en) * | 2019-11-28 | 2021-03-23 | 国网江苏省电力有限公司镇江供电分公司 | 110kV line disconnection protection method for collecting bus voltage of line load end |
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Application publication date: 20121024 |