CN100356651C - Automatic tracking protector for earth leakage and operation method thereof - Google Patents
Automatic tracking protector for earth leakage and operation method thereof Download PDFInfo
- Publication number
- CN100356651C CN100356651C CNB2004100726221A CN200410072622A CN100356651C CN 100356651 C CN100356651 C CN 100356651C CN B2004100726221 A CNB2004100726221 A CN B2004100726221A CN 200410072622 A CN200410072622 A CN 200410072622A CN 100356651 C CN100356651 C CN 100356651C
- Authority
- CN
- China
- Prior art keywords
- leakage
- electric leakage
- threshold value
- current
- leakage current
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Images
Landscapes
- Emergency Protection Circuit Devices (AREA)
Abstract
The present invention relates to an automatic tracking protector for electric leakage and an operation method thereof. The protector of the present invention is composed of an air circuit breaker or relay, a single chip computer, a zero sequence current transformer, an electric leakage signal amplifying circuit and a power source, wherein the single chip computer has the following operating programs: (1) the single chip computer is initialized; (2) the amplitude value and the phase angle of leakage current are measured; (3) the variation value of the leakage current is calculated; (4) whether the variation value of the leakage current is larger than 10% of the threshold value of electric leakage operation or not is judged; (5) the duration time which is less than 10% of the threshold value of electric leakage operation is judged; (6) the threshold value of the operation is changed. When the leakage current reaches or exceeds the threshold value of the current of electric leakage operation, the single chip computer sends out an electric leakage tripping command to trigger a thyristor to enable the air circuit breaker or relay to operate, fault circuits are switched off by the air circuit breaker or relay, and then, the electric leakage caused by faults can be prevented. The present invention can also be additionally provided with auxiliary components, such as an electric leakage simulative generator, and/or a leakage current displaying circuit, and/or a frequency detecting circuit.
Description
Technical field
Technical scheme of the present invention relates to a kind of automatic disconnection emergency protective circuit device that the undesirable variation that departs from the normal electrical working condition is directly reacted, specifically a kind of Electric Leakage AutoTracking Protector And Operation Method.
Background technology
Electric leakage protection technology is a kind of prevent from the to leak electricity fire and the personal technology of getting an electric shock of protection of extensive use in low voltage electric network.Along with the raising of people to Electrical Safety understanding, the application of electric leakage protection technology is also enlarging.Yet earth leakage protective and mains supply become a pair of contradiction of people's electricity consumption.From the Electrical Safety angle, wish that earth leakage protective device is action just in case appearance is leaked electricity, fire and personal electric shock in time prevent to leak electricity; From the operational percentage of electrical network, hope can be powered continuously, avoids causing economic loss and inconvenience owing to have a power failure to people.In practical operation, people have taked a half-way house, and promptly leakage current hour does not carry out earth leakage protective in the electrical network, improves the electrical network operational percentage; When leakage current in the electrical network is big, carry out earth leakage protective, improve electrical safety.Yet, the electric leakage situation more complicated in the actual electric network, the normal electric leakage in the not only different electrical networks is different, differs bigger sometimes; Even if the normal electric leakage in the same electrical network neither be constant always, can change along with the variation of environmental condition, particularly the normal leakage current of F of electrical network differs bigger when dry season and wet season.In electrical network, adopt fixing residual operating current threshold value, be difficult to realize correct fault creepage protecting.If the residual operating current threshold value that adopts in electrical network is less, though realized the protection of fault electric leakage, the normal leakage current that has arrived the wet season electrical network increases, earth leakage protective device is action often, reduced the operational percentage of electrical network, even can cause economic loss to the user; If the residual operating current threshold value that adopts in electrical network is bigger; improved the operational percentage of electrical network at wet season; and arrived dry season; the normal leakage current of electrical network reduces; in this case, if the fault electric leakage, earth leakage protective device just may be failure to actuate; influence people's Electrical Safety, also can cause economic loss.Though in the prior art; the employing that has has the protector of many grades of residual operating current threshold values; at normal leakage current less residual operating current threshold value hour is set; bigger residual operating current threshold value is set when normal leakage current is big; improved the effect of earth leakage protective device to a certain extent; but because the residual operating current threshold value that is provided with can not change automatically; when variation greatly takes place because of weather or other ambient conditions change in the normal electric leakage of electrical network; earth leakage protective device is still worked under original residual operating current threshold value, still can't provide correct protection to the fault leakage current.Concerning the general user, they can't know how many normal leakage currents in the electrical network is, when the normal leakage current in electrical network was with environmental change especially, the user more can't be provided with the residual operating current threshold value according to actual conditions.CN 99120647.9 and CN 99230358.3 disclose a kind of " intelligent controller of communicable plastics casing circuit breaker ", wherein She Ji phase-locked loop frequency tracking circuit is used for automatic tracking frequency variation, can not be used for variation from the normal leakage current of motion tracking electrical network, and its frequency tracking circuit complexity; CN 93244614.0 discloses a kind of " intelligent multi-function load governor ", though wherein mentioned the tracking memory circuit, be applicable to transgression for using electricity such as restriction electric heating appliance, and earth leakage protective is irrelevant; In CN 98118285.2 and CN 98245498.8 disclosed " microcomputerized digital intelligent leakage protector ",,, the normal electric leakage and the fault electric leakage of electrical network are not distinguished only at phase demodulation amplitude discrimination technology though the characteristics of electric leakage from motion tracking are arranged.In a word, existing earth leakage protective device does not all overcome the contradiction between electrical network operational percentage and the electrical safety.
Summary of the invention
Technical problem to be solved by this invention is: a kind of automatic tracking protector for earth leakage is provided; it is distinguished the normal electric leakage and the fault electric leakage of electrical network; variation according to the normal leakage current of electrical network changes the residual operating current threshold value automatically; change or not under the situation of change at the normal leakage current of electrical network; can both correctly protect the fault electric leakage; ensure the operational percentage of electrical network, overcome the contradiction between electrical network operational percentage and the electrical safety.
The present invention solves this technical problem the technical scheme that is adopted: automatic tracking protector for earth leakage of the present invention; comprise air circuit or relay, single-chip microcomputer, zero sequence current mutual inductor, electric leakage signal amplifying circuit and power supply part, wherein single-chip microcomputer has following operation sequence:
The first step, after powering on, general register and special register are carried out initialization, the particularly initialization of the register of timer and A/D conversion, sample frequency and sampling window cycle are set, sample frequency is much larger than the frequency of electric leakage signal, and the sampling window cycle is the cycle of electric leakage signal, changes for second step after initialization is finished;
Second step, according to sample frequency and window period electric leakage signal is gathered, after finishing the sampling of one-period, calculate the amplitude and the phase angle of leakage current, judge that leakage current whether greater than electric leakage action threshold value, when leakage current moves threshold value more than or equal to electric leakage, sends the instruction of threading off of leaking electricity, when leakage current moves threshold value less than electric leakage, changeed for the 3rd step;
The 3rd step according to the amplitude and the phase angle of the leakage current of firm detection, compared with the amplitude and the phase angle of the leakage current of former detection, calculated the changing value of leakage current, changeed for the 4th step;
The 4th step, whether judge the leakage current changing value greater than setting, when the leakage current changing value moves threshold value greater than 10% electric leakage, changeed for second step, when the leakage current changing value moves threshold value less than 10% electric leakage, changeed for the 5th step;
The 5th step, judge duration less than 10% electric leakage action threshold value, when being set, do not change for second step numerical value when the duration, go on foot to back commentaries on classics the 6th when the duration;
In the 6th step, when electric leakage is changed to when increasing, electric leakage action threshold value increases, and when electric leakage is changed to when reducing, electric leakage action threshold value reduces, and changes for second step.
Automatic tracking protector for earth leakage of the present invention also can add following auxiliary part: electric leakage simulative generator, leakage current display circuit and frequency detection circuit.
Automatic tracking protector for earth leakage of the present invention realizes that electric leakage from the operation method of motion tracking and protection process is: the leakage current in the zero sequence current mutual inductor detection of grid, and leakage current is transformed to voltage signal is input to the electric leakage signal amplifying circuit; Be directly inputted in the single-chip microcomputer by the electric leakage signal after the amplification of electric leakage signal amplifying circuit; Single-chip microcomputer carries out following processing to leakage current: single-chip microcomputer is by constantly detecting leakage current amplitude and phase angle, analyze the variation of amplitude and phase angle, whether the variation of judging the leakage current of current time belongs to the normal leakage current variation of electrical network, single-chip microcomputer is judged as it and belongs to the normal leakage current variation of electrical network when leakage current changes slowly, single-chip microcomputer changes the residual operating current threshold value automatically thus, when normal leakage current increases, the residual operating current threshold value increases, when normal leakage current reduces, the residual operating current threshold value reduces, thereby realization residual operating current threshold value is carried out earth leakage protective from motion tracking along with the normal leakage current of electrical network changes and changes; When leakage current met or exceeded the residual operating current threshold value, single-chip microcomputer sent electric leakage dropout order, makes the air circuit or the actuating of relay, and air circuit or relay disengagement failure circuit are protected the fault electric leakage; Power supply is single-chip microcomputer and other circuit supply.
Single-chip microcomputer does not just send the electric leakage order of threading off after greater than electric leakage action threshold value immediately detecting leakage current, time-delay between 0 to 1000 millisecond is arranged between this, this section delay time is adjustable, when leakage current big more with the ratio of residual operating current threshold value, delay time is short more, when leakage current greater than duration of residual operating current threshold value during less than delay time, single-chip microcomputer does not send the electric leakage order of threading off.Therefore; protector for different residual operating current threshold values; difference operate time under the identical leakage current; the protector that the residual operating current threshold value is big; its operate time is longer, not even action, and the little protector of residual operating current threshold value; its operate time is shorter, and therefore earth leakage protective device of the present invention has possessed earth leakage protective inverse time protection characteristic.
Auxiliary part in the automatic tracking protector for earth leakage of the present invention realizes that electric leakage from the operation method of the booster action of motion tracking and protection is: single-chip microcomputer is delivered to the leakage current display circuit with leakage current, the leakage current display circuit shows leakage current, and shows the residual operating current threshold value and show the leakage current that causes action; Frequency detection circuit directly obtains AC signal and carries out halfwave rectifier to single-chip microcomputer from electrical network, and single-chip microcomputer detects its input signal, and the signal of one-period is carried out timing, detects the time of one-period, realize mains frequency from motion tracking; Electric leakage simulation generation breadboardin produces the fault electric leakage, when single-chip microcomputer detects the simulated failure electric leakage, also sends electric leakage dropout order, is used to check whether protector work of the present invention is normal; Power supply is these circuit supplies simultaneously.
Beneficial effect of the present invention compared with prior art, has the following advantages:
(1) automatic tracking protector for earth leakage of the present invention can detect leakage current amplitude and phase angle; when electric current changes when belonging to the normal leakage current of electrical network and changing; single-chip microcomputer can change the residual operating current threshold value automatically; that is to say that the residual operating current threshold value is along with the normal leakage current of electrical network changes and changes; realize earth leakage protective from motion tracking; thereby improved the normal leakage current of electrical network than the operational percentage under the big situation, also ensured correct protection to the fault electric leakage.And existing earth leakage protective device can not be realized the automatic change of residual operating current threshold value, and protector of the present invention is to carry out earth leakage protective under the situation that normal electric leakage of electrical network and fault leak electricity from motion tracking distinguishing.
(2) automatic tracking protector for earth leakage of the present invention by to the electric network source frequency from motion tracking, can be suitable for the earth leakage protective of different frequency electrical network, or when mains frequency changes, also can realize the accurate protection of leaking electricity having enlarged application scenario of the present invention.
(3) automatic tracking protector for earth leakage of the present invention is realized the demonstration of current leakage current also realizing the demonstration of residual operating current threshold value by its leakage current display circuit, and realizes causing the demonstration of the leakage current value of action.
(4) automatic tracking protector for earth leakage of the present invention has been realized earth leakage protective anti-time limit characteristic, and the ratio of its operate time and leakage current and residual operating current threshold value is inversely proportional to.In the three-level protective of electric leakage; electric leakage action threshold value maximum in total protection; electric leakage action threshold value minimum in the terminal protection; electric leakage action threshold value in branch's protection is placed in the middle; under identical leakage current situation; for the earth leakage protective device in total protection; ratio minimum with its residual operating current threshold value; delay time is the longest, and the delay time in the terminal protection is the shortest, placed in the middle in branch's protection; so the protector in the end moves the earliest; with the leak current fault excision, this fashion does not reach the delay time of total protection and branch's protection, and the protector of total protection and branch's protection is failure to actuate.Therefore adopt earth leakage protective device of the present invention can avoid earth leakage protective overstep tripping, reduce the area that has a power failure, ensured the operational percentage of electrical network.
Description of drawings
The present invention is further described below in conjunction with drawings and Examples.
Fig. 1 is the connection block diagram between each part of the present invention.
Fig. 2 is the connection block diagram that is added with between each part of the present invention of auxiliary circuit.
Fig. 3 is circuit catenation principle figure of the present invention.
Fig. 4 is that chip microcontroller is leaked electricity from the flow chart of motion tracking among the present invention.
Among the figure, 1. zero sequence current mutual inductor, 2. electric leakage signal amplifying circuit, 3. air circuit or relay, 4. electric leakage simulative generator, 5. single-chip microcomputer, 6. leakage current display circuit, 7. frequency detection circuit, 8. power supply.
Embodiment
Embodiment
Fig. 1 shows that automatic tracking protector for earth leakage of the present invention comprises single-chip microcomputer (5), zero sequence current mutual inductor (1), electric leakage signal amplifying circuit (2), power supply (8) and air circuit or relay (3).Wherein constitute the leakaging signal detecting circuit of automatic tracking protector for earth leakage of the present invention by single-chip microcomputer (5), zero sequence current mutual inductor (1), electric leakage signal amplifying circuit (2) and power supply (8).Their realize that electric leakage from the operation method of motion tracking and protection process is: the leakage current in zero sequence current mutual inductor (1) detection of grid, and leakage current is transformed to voltage signal is input to electric leakage signal amplifying circuit (2); Be directly inputted in the single-chip microcomputer (5) by the electric leakage signal after electric leakage signal amplifying circuit (2) amplification; Single-chip microcomputer (5) is handled leakage current, be that single-chip microcomputer (5) is by constantly detecting leakage current amplitude and phase angle, analyze the variation of amplitude and phase angle, whether the variation of judging the leakage current of current time belongs to the normal leakage current variation of electrical network, single-chip microcomputer (5) is judged as it and belongs to the normal leakage current variation of electrical network when leakage current changes slowly, single-chip microcomputer (5) changes the residual operating current threshold value automatically thus, when normal leakage current increases, the residual operating current threshold value increases, when normal leakage current reduces, the residual operating current threshold value reduces, thereby realization residual operating current threshold value is carried out earth leakage protective from motion tracking along with the normal leakage current of electrical network changes and changes; When leakage current met or exceeded the residual operating current threshold value, single-chip microcomputer (5) sent electric leakage dropout order through time-delay, makes air circuit or relay (3) action, and air circuit or relay (3) disengagement failure circuit is protected the fault electric leakage; Power supply (8) is single-chip microcomputer and other circuit supply.
Fig. 2 shows; the automatic tracking protector for earth leakage of the present invention that is added with auxiliary circuit comprises single-chip microcomputer (5); zero sequence current mutual inductor (1); electric leakage signal amplifying circuit (2); electric leakage simulative generator (4); leakage current display circuit (6); frequency detection circuit (7); power supply (8) and air circuit or relay (3) are wherein by single-chip microcomputer (5); zero sequence current mutual inductor (1); electric leakage signal amplifying circuit (2); electric leakage simulative generator (4); leakage current display circuit (6); frequency detection circuit (7) and power supply (8) constitute the leakaging signal detecting circuit of automatic tracking protector for earth leakage of the present invention.Their realize that electric leakage from the operation method of motion tracking and protection process and booster action is: the leakage current in zero sequence current mutual inductor (1) detection of grid, and leakage current is transformed to voltage signal is input to electric leakage signal amplifying circuit (2); Be directly inputted in the single-chip microcomputer (5) by the electric leakage signal after electric leakage signal amplifying circuit (2) amplification; Single-chip microcomputer (5) carries out following processing to leakage current: single-chip microcomputer (5) is by constantly detecting leakage current amplitude and phase angle, analyze the variation of amplitude and phase angle, whether the variation of judging the leakage current of current time belongs to the normal leakage current variation of electrical network, single-chip microcomputer (5) is judged as it and belongs to the normal leakage current variation of electrical network when leakage current changes slowly, single-chip microcomputer (5) changes the residual operating current threshold value automatically thus, when normal leakage current increases, the residual operating current threshold value increases, when normal leakage current reduces, the residual operating current threshold value reduces, thereby realization residual operating current threshold value is carried out earth leakage protective from motion tracking along with the normal leakage current of electrical network changes and changes; When leakage current met or exceeded the residual operating current threshold value, single-chip microcomputer (5) sent electric leakage dropout order through time-delay and makes air circuit or relay (3) action, and air circuit or relay (3) disengagement failure circuit is protected the fault electric leakage; Circuit (4) takes place in the electric leakage simulation simulates the electric leakage of generation fault, when single-chip microcomputer (5) detects the simulated failure electric leakage, also sends the electric leakage dropout and orders, and is used to check whether protector of the present invention is normal; Single-chip microcomputer (5) is delivered to leakage current display circuit (6) with leakage current, and leakage current display circuit (6) shows leakage current, and shows the residual operating current threshold value and show the leakage current that causes action; Frequency detection circuit (7) directly obtains AC signal and carries out halfwave rectifier to single-chip microcomputer (5) from electrical network, single-chip microcomputer (5) detects its input signal, and the signal of one-period carried out timing, detect the time of one-period, realize mains frequency from motion tracking; Power supply (8) is single-chip microcomputer and other circuit supply.
Fig. 3 shows that zero sequence current mutual inductor LH (1) connects electric leakage signal amplifying circuit (2), provides electric leakage signal for single-chip microcomputer U1 (5) together; Leakage current display circuit (6) is subjected to the control of single-chip microcomputer U1 (5), shows leakage current, and can show the leakage current when electric leakage action threshold value and electric leakage are moved; Single-chip microcomputer U1 (5) also controls air circuit or relay (3), realizes the earth leakage protective action; Circuit (4) takes place and is connected with zero sequence current mutual inductor LH (1) in the electric leakage simulation; Frequency detection circuit (7) inputs to single-chip microcomputer U1 (5) with current signal; Power supply (8) is single-chip microcomputer and other circuit supply.
As shown in Figure 3, zero sequence current mutual inductor LH (1) comprises two secondary that are made of respectively two coils, and one of them secondary is connected to electric leakage signal amplifying circuit (2), and another secondary and button SW1 and resistance R 1 constitute the electric leakage simulation circuit (4) takes place.
As shown in Figure 3, electric leakage signal amplifying circuit (2) is made of R3, C5, U2A, R4, R5, R6, R7 and R8, the output of zero sequence current mutual inductor LH (1) meets R3, C5, leakage current signal is transformed to voltage signal, the electric leakage signal amplifying circuit (2) that constitutes via U2A, R4, R5, R6, R7 amplifies signal, inputs to single-chip microcomputer U1 (5) through R8.
As shown in Figure 3, air circuit or relay (3) are subjected to the control of single-chip microcomputer U1 (5) by R2 and bidirectional triode thyristor SCR1, single-chip microcomputer when leakage current meets or exceeds the residual operating current threshold value (5) sends electric leakage dropout order, make air circuit or relay (3) action, air circuit or relay (3) disengagement failure circuit.
As shown in Figure 3; another secondary of zero sequence current mutual inductor LH (1) and button SW1 and resistance R 1 constitute the electric leakage simulation circuit (4) take place; when pressing SW1; zero sequence current mutual inductor LH (1) will produce the electric leakage signal of a simulation; after single-chip microcomputer U1 (5) detects this signal; to send the earth leakage protective instruction; it is single-chip microcomputer (5) output high level; trigger bidirectional triode thyristor SCR1 by R2; whether make air circuit or relay (3) action, it is normal to be used for check protection device earth leakage protective performance.
As shown in Figure 3, the electric leakage signal after the single-chip microcomputer U1 (5) among the present invention accepts electric leakage signal amplifying circuit (2) and amplifies and the current signal of frequency detection circuit (7), control leakage current display circuit (6) and air circuit or relay (3).Single-chip microcomputer U1 (5) samples to leakage current, sample frequency is greater than the frequency of electric leakage signal, the present embodiment sample frequency adopts the frequency of 40 times of electric leakage signals, single-chip microcomputer U1 (5) notes the leakage current waveform, and calculate its effective value, simultaneously the time of zero crossing is carried out record, go out the phase angle of leakage current, promptly finished the amplitude of leakage current and the detection of phase angle according to the leakage current computation of Period.Single-chip microcomputer U1 (5) constantly detects and the amplitude and the phase angle that calculate leakage current, notes the amplitude and the phase angle of leakage current simultaneously.Single-chip microcomputer U1 (5) is according to the information of noting leakage current, the analysis leakage current changes, when the leakage current rate of change hour, adopt variation in the present embodiment less than 10% electric leakage action threshold value, the normal electric leakage of thinking electrical network changes, when the leakage current rate of change is big, adopt variation in the present embodiment greater than 10% electric leakage action threshold value, think to have in the electrical network equipment to occur unusually.When grid power leakage belonged to normal electric leakage, single-chip microcomputer U1 (5) changed electric leakage action threshold value according to the leakage current value of electrical network, and under electrical network normal current increase situation, electric leakage action threshold value increases, and reduces under the situation at the electrical network normal current, and electric leakage action threshold value reduces.The variation of electric leakage action threshold value is provided with higher limit and lower limit, higher limit is decided to be 150mA between the 1000mA according to ambient conditions, lower limit is decided to be 75mA between the 500mA according to ambient conditions, present embodiment lower limit value adopts 100mA, higher limit to adopt 500mA, and the normal leakage current transformation period of electrical network was less than 10 minutes to 60 minutes, adopted 20 minutes in the present embodiment, electric leakage action threshold value can not change yet.When breaking down electric leakage in electrical network, single-chip microcomputer U1 (5) can not change electric leakage action threshold value.When the fault leakage current reaches electric leakage action threshold value; single-chip microcomputer is not to send the earth leakage protective instruction immediately; but through the time delays between 0 to 1000 millisecond; this section delay time is adjustable; send the earth leakage protective instruction; the fault leakage current is big more with the ratio of electric leakage action threshold value; delay time is short more; after time-delay; single-chip microcomputer (5) output high level triggers bidirectional triode thyristor SCR1 by R2, and air circuit or relay (3) are threaded off; carry out earth leakage protective, realized the automatic track protection of electric leakage of the present invention.
As shown in Figure 3, resistance R 9, R10, R11, R12, R13, R14, R15, charactron LDE1, triode T2, T3, T4 have constituted leakage current display circuit (6), this circuit is under the control of single-chip microcomputer U1 (5), adopt the scanning display mode, make triode T2, T3, the T4 conducting that circulates successively, select the charactron conducting of corresponding positions respectively, the charactron number that will show is by the RB1-RB7 output of single-chip microcomputer simultaneously, light charactron, thereby realized the demonstration of single-chip microcomputer U1 (5) output information.Leakage current value when the information of single-chip microcomputer U1 (5) output comprises leakage current value, electric leakage action threshold value, action.
As shown in Figure 3, R16, D5 constitute frequency detection circuit (7), R16, D5 input to single-chip microcomputer U1 (5) with power supply signal, single-chip microcomputer U1 (5) adopts timer internal that power supply signal is carried out timing measuring, when mains frequency changes, the timer value of single-chip microcomputer U1 (5) also just changes, realization to mains frequency from motion tracking, single-chip microcomputer U1 (5) is when carrying out signals collecting, according to single-chip microcomputer U1 (5) the timer value decision sampling period, realize that weekly the data of gathering in the phase are constant, reduced the error of data processing, improved the certainty of measurement of electric current.
As shown in Figure 3, the power supply of leakaging signal detecting circuit (8) is made of diode D1, D2, D3, D4, integrated voltage stabilizing T1 and C1, C2, C3, C4, supply voltage carries out voltage stabilizing by diode D1, D2, D3, D4 rectification by integrated voltage stabilizing T1, and C1, C2, C3, C4 carry out filtering to power supply.
Fig. 4 shows that chip microcontroller is leaked electricity from the operation sequence of motion tracking among the present invention:
(1) power on after, general register and special register are carried out initialization, the particularly initialization of the register of timer and A/D conversion, sample frequency and sampling window cycle are set, sample frequency is much larger than the frequency of electric leakage signal, the sampling window cycle is the cycle of electric leakage signal, changes for (2) step after initialization is finished;
(2) according to sample frequency and window period electric leakage signal is gathered, after finishing the sampling of one-period, calculate the amplitude and the phase angle of leakage current, judge that whether leakage current is greater than electric leakage action threshold value, when leakage current moves threshold value more than or equal to electric leakage, send electric leakage dropout instruction, when leakage current moves threshold value less than electric leakage, change (3) and go on foot;
(3) according to the amplitude and the phase angle of the leakage current that has just detected, compare with the amplitude and the phase angle of the leakage current of former detection, calculate the changing value of leakage current, changeed for (4) step;
(4) whether judge the leakage current changing value greater than setting, when the leakage current changing value moves threshold value greater than 10% electric leakage, changeed for (2) step, when the leakage current changing value moves threshold value less than 10% electric leakage, change (5) and go on foot;
(5) judge duration, do not change for (2) step when numerical value is set, go on foot to back commentaries on classics (6) when the duration when the duration less than electric leakage action threshold value;
(6) be changed to when increasing when electric leakage, electric leakage action threshold value increases, and when electric leakage is changed to when reducing, electric leakage action threshold value reduces, and changes for (2) step.
Set in the present embodiment:
(4) when the leakage current changing value moves threshold value greater than 10% electric leakage, changeed for (2) step, when the leakage current changing value moves threshold value less than 10% electric leakage, change (5) and go on foot;
(5) judge duration, do not change for (2) step when numerical value is set, go on foot to back commentaries on classics (6) when the duration when the duration less than 10% electric leakage action threshold value.
Claims (9)
1. an automatic tracking protector for earth leakage comprises air circuit or relay, single-chip microcomputer, zero sequence current mutual inductor, electric leakage signal amplifying circuit and power supply, it is characterized in that wherein single-chip microcomputer has following operation sequence:
The first step, after powering on, general register and special register are carried out initialization, the particularly initialization of the register of timer and A/D conversion, sample frequency and sampling window cycle are set, sample frequency is much larger than the frequency of electric leakage signal, and the sampling window cycle is the cycle of electric leakage signal, changes for second step after initialization is finished;
Second step, according to sample frequency and window period electric leakage signal is gathered, after finishing the sampling of one-period, calculate the amplitude and the phase angle of leakage current, judge that leakage current whether greater than electric leakage action threshold value, when leakage current moves threshold value more than or equal to electric leakage, sends the instruction of threading off of leaking electricity, when leakage current moves threshold value less than electric leakage, changeed for the 3rd step;
The 3rd step according to the amplitude and the phase angle of the leakage current of firm detection, compared with the amplitude and the phase angle of the leakage current of former detection, calculated the changing value of leakage current, changeed for the 4th step;
The 4th step, whether judge the leakage current changing value greater than setting, when the leakage current changing value moves threshold value greater than 10% electric leakage, changeed for second step, when the leakage current changing value moves threshold value less than 10% electric leakage, changeed for the 5th step;
The 5th step, judge duration less than 10% electric leakage action threshold value, when being set, do not change for second step numerical value when the duration, go on foot to back commentaries on classics the 6th when the duration;
In the 6th step, when electric leakage is changed to when increasing, electric leakage action threshold value increases, and when electric leakage is changed to when reducing, electric leakage action threshold value reduces, and changes for second step.
2. automatic tracking protector for earth leakage according to claim 1; it is characterized in that: single-chip microcomputer does not just send the electric leakage order of threading off after greater than electric leakage action threshold value immediately detecting leakage current; time-delay between 0 to 1000 millisecond is arranged between this; this section delay time is adjustable; when leakage current big more with the ratio of residual operating current threshold value; delay time is short more; when the duration of leakage current greater than the residual operating current threshold value; during less than delay time, single-chip microcomputer does not send electric leakage dropout order.
3. automatic tracking protector for earth leakage according to claim 1; it is characterized in that: single-chip microcomputer is sampled to leakage current; sample frequency is the frequency of 40 times of electric leakage signals; single-chip microcomputer is noted the leakage current waveform; and calculate its effective value; simultaneously the time of zero crossing is carried out record; go out the phase angle of leakage current according to the leakage current computation of Period; the amplitude of leakage current and the detection of phase angle have promptly been finished; single-chip microcomputer is according to the information of noting leakage current; the electric current of analyzing adjacent two cycles changes, and when the variation of leakage current rate of change less than 10% electric leakage action threshold value, thinks that the normal electric leakage of electrical network changes; when of the variation of leakage current rate of change greater than 10% electric leakage action threshold value; think to have in the electrical network equipment to occur unusually, when grid power leakage belonged to normal electric leakage, single-chip microcomputer changed electric leakage action threshold value according to the leakage current value of electrical network; under electrical network normal current increase situation; electric leakage action threshold value increases, and reduces under the situation at the electrical network normal current, and electric leakage action threshold value reduces.
4. automatic tracking protector for earth leakage according to claim 1, it is characterized in that: the variation of electric leakage action threshold value is provided with higher limit and lower limit, higher limit is decided to be 150mA between the 1000mA according to ambient conditions, lower limit is decided to be 75mA between the 500mA according to ambient conditions; The normal leakage current transformation period of electrical network was less than 10 minutes to 60 minutes, and electric leakage action threshold value can not change.
5. automatic tracking protector for earth leakage according to claim 4 is characterized in that: the higher limit of the variation of electric leakage action threshold value is decided to be 500mA, and lower limit is decided to be 100mA; The normal leakage current transformation period of electrical network was less than 20 minutes, and electric leakage action threshold value can not change.
6. automatic tracking protector for earth leakage according to claim 1 is characterized in that: when breaking down electric leakage in electrical network, single-chip microcomputer can not change electric leakage action threshold value.
7. automatic tracking protector for earth leakage according to claim 1 is characterized in that: be added with the auxiliary part of electric leakage simulative generator, leakage current display circuit and frequency detection circuit.
8. the described automatic tracking protector for earth leakage of claim 1 realizes that electric leakage from the operation method of motion tracking and protection process is: the leakage current in the zero sequence current mutual inductor detection of grid, and leakage current is transformed to voltage signal is input to the electric leakage signal amplifying circuit; Be directly inputted in the single-chip microcomputer by the electric leakage signal after the amplification of electric leakage signal amplifying circuit; Single-chip microcomputer carries out following processing to leakage current: single-chip microcomputer is by constantly detecting leakage current amplitude and phase angle, analyze the variation of amplitude and phase angle, whether the variation of judging the leakage current of current time belongs to the normal leakage current variation of electrical network, single-chip microcomputer is judged as it and belongs to the normal leakage current variation of electrical network when leakage current changes slowly, single-chip microcomputer changes the residual operating current threshold value automatically thus, when normal leakage current increases, the residual operating current threshold value increases, when normal leakage current reduces, the residual operating current threshold value reduces, thereby realization residual operating current threshold value is carried out earth leakage protective from motion tracking along with the normal leakage current of electrical network changes and changes; When leakage current met or exceeded the residual operating current threshold value, single-chip microcomputer sent electric leakage dropout order, makes the air circuit or the actuating of relay, air circuit or relay disengagement failure circuit; Power supply is single-chip microcomputer and other circuit supply.
9. the described automatic tracking protector for earth leakage of claim 7 realizes that electric leakage from the operation method of the booster action of motion tracking and protection process is: single-chip microcomputer is delivered to the leakage current display circuit with leakage current, the leakage current display circuit shows leakage current, and shows the residual operating current threshold value and show the leakage current that causes action; Frequency detection circuit directly obtains AC signal and carries out halfwave rectifier to single-chip microcomputer from electrical network, and single-chip microcomputer detects its input signal, and the signal of one-period is carried out timing, detects the time of one-period, realize mains frequency from motion tracking; Electric leakage simulation generation breadboardin produces the fault electric leakage, when single-chip microcomputer detects the simulated failure electric leakage, also sends electric leakage dropout order; Power supply is these circuit supplies simultaneously.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2004100726221A CN100356651C (en) | 2004-11-04 | 2004-11-04 | Automatic tracking protector for earth leakage and operation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2004100726221A CN100356651C (en) | 2004-11-04 | 2004-11-04 | Automatic tracking protector for earth leakage and operation method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1604418A CN1604418A (en) | 2005-04-06 |
| CN100356651C true CN100356651C (en) | 2007-12-19 |
Family
ID=34666850
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB2004100726221A Expired - Fee Related CN100356651C (en) | 2004-11-04 | 2004-11-04 | Automatic tracking protector for earth leakage and operation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN100356651C (en) |
Families Citing this family (17)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101958528B (en) * | 2010-10-18 | 2013-07-03 | 吕纪文 | Leakage protection method and device |
| CN102222886A (en) * | 2011-06-23 | 2011-10-19 | 周庆生 | Protection device and method for high-voltage vacuum power distribution equipment for mining |
| CN102231510B (en) * | 2011-07-01 | 2014-04-09 | 河北工业大学 | Pulsating DC (direct current) aftercurrent protector and running method thereof |
| CN102354960A (en) * | 2011-09-28 | 2012-02-15 | 陈和娟 | Mine high-voltage vacuum power distribution protecting apparatus and control method |
| CN102386610A (en) * | 2011-12-13 | 2012-03-21 | 赵磊 | Intelligent leakage protection switch |
| CN103913659B (en) * | 2014-03-30 | 2017-02-15 | 河北工业大学 | instantaneous protection tester and operation method thereof |
| CN105281285A (en) * | 2014-06-06 | 2016-01-27 | 上海航空电器有限公司 | High-power current-limiting and overcurrent protection circuit suitable for test equipment |
| CN104297682B (en) * | 2014-11-10 | 2017-07-11 | 河北工业大学 | The electric life test protection device of breaker and its method for operation |
| CN104753024A (en) * | 2015-03-18 | 2015-07-01 | 胡妍 | Electricity leakage protecting method for preventing symmetric electricity leakage |
| CN108306256B (en) * | 2018-02-08 | 2019-07-30 | 常熟开关制造有限公司(原常熟开关厂） | Prevent the method and residual current circuit breaker of residual current circuit breaker malfunction |
| CN109061360B (en) * | 2018-06-21 | 2020-12-15 | 浙江巨磁智能技术有限公司 | Leakage protection safety self-checking system and self-checking method thereof |
| CN109238335B (en) * | 2018-08-13 | 2021-01-12 | 湖南星邦智能装备股份有限公司 | Sensor fault judgment method |
| CN110277763A (en) * | 2019-07-08 | 2019-09-24 | 上海磊跃自动化设备有限公司 | A kind of earth leakage protective device with low current trial jump function |
| CN111934280B (en) * | 2020-09-09 | 2023-01-24 | 南方电网数字电网研究院有限公司 | Electric leakage fault detection method and device, storage medium and power distribution gateway |
| CN113421802B (en) * | 2021-06-07 | 2023-06-13 | 武汉特试特科技股份有限公司 | Low-voltage intelligent circuit breaker protection method and system |
| CN113985158B (en) * | 2021-09-18 | 2023-09-12 | 河北工业大学 | Residual current protection inspection method, inspection device, electronic apparatus, and storage medium |
| CN113820566B (en) * | 2021-10-10 | 2023-05-09 | 西安科技大学 | Leakage selecting method for coal mine power grid |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1257334A (en) * | 1999-12-16 | 2000-06-21 | 常熟开关厂 | Intelligent controller for communicable plastics casing circuit breaker |
| CN2582242Y (en) * | 2002-11-16 | 2003-10-22 | 郑祥衡 | Intelligence, phase-discrimination, amplitude-discrimination and leakage comprehensive protective device |
-
2004
- 2004-11-04 CN CNB2004100726221A patent/CN100356651C/en not_active Expired - Fee Related
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1257334A (en) * | 1999-12-16 | 2000-06-21 | 常熟开关厂 | Intelligent controller for communicable plastics casing circuit breaker |
| CN2582242Y (en) * | 2002-11-16 | 2003-10-22 | 郑祥衡 | Intelligence, phase-discrimination, amplitude-discrimination and leakage comprehensive protective device |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1604418A (en) | 2005-04-06 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN100356651C (en) | Automatic tracking protector for earth leakage and operation method thereof | |
| CN102279326B (en) | Electrical appliance recognition method and household user carbon emission metering system applying same | |
| CN101420116B (en) | Intelligent integrated electricity leakage protection device | |
| CN102901936B (en) | Poweroff detection method of alternating current power supply and poweroff protection method of direct current inverter compressor | |
| CN108693499B (en) | User power load identification intelligent electric energy meter detection method and device | |
| CN110412346B (en) | Metering type intelligent circuit breaker based on Internet of things | |
| CN106026651A (en) | System and Method for a Switched-Mode Power Supply | |
| CN204462252U (en) | A kind of intelligent electric meter control circuit | |
| CN102231510B (en) | Pulsating DC (direct current) aftercurrent protector and running method thereof | |
| CN210835064U (en) | Metering type intelligent circuit breaker based on Internet of things | |
| CN104979895A (en) | Intelligent digital dual-power switching system | |
| CN100539345C (en) | Dead-space free circuit breaker for earth leakage abrupt change and operation method thereof | |
| CN210071975U (en) | Branch monitoring device and monitoring system suitable for low-voltage distribution area topology identification | |
| Hernández et al. | Design of a SoC architecture for the edge computing of NILM techniques | |
| CN201360135Y (en) | Intelligent integrated leakage protection device | |
| CN202094603U (en) | Protector for residual currents of pulse direct currents | |
| CN210323280U (en) | Residual current protection circuit breaker | |
| CN109856489B (en) | Load simulation device and method for testing performance of direct current power supply system | |
| CN206116325U (en) | Automatic heavy switching -on device's contact protection device | |
| CN2757401Y (en) | Leakage automatic tracing protector | |
| CN107248658A (en) | It is a kind of based on metering and remote control power-line plug | |
| CN108512308B (en) | Building energy consumption collection system | |
| CN207408504U (en) | A kind of load detecting circuit and electronic equipment | |
| CN106855700B (en) | A kind of control of intelligent terminal for distribution line on-pole switch | |
| CN104865428A (en) | Automatic switching device of three-phase three-wire electric energy meter and three-phase four-wire electric energy meter |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| EE01 | Entry into force of recordation of patent licensing contract |
Assignee: Baoding Unt Electric Co., Ltd. Assignor: Hebei University of Technology Contract fulfillment period: 2004.12.1 to 2014.11.30 Contract record no.: 2008990000951 Denomination of invention: Automatic tracking protector for earth leakage and operation method thereof Granted publication date: 20071219 License type: Exclusive license Record date: 20081027 |
|
| LIC | Patent licence contract for exploitation submitted for record |
Free format text: EXCLUSIVE LICENSE; TIME LIMIT OF IMPLEMENTING CONTACT: 2004.12.1 TO 2014.11.30; CHANGE OF CONTRACT Name of requester: BAODING CITY YOUNAITE ELECTRIC APPLICANCE CO., LTD Effective date: 20081027 |
|
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20071219 Termination date: 20181104 |