CN202019189U - Inrush current controller and power distribution protection system - Google Patents
Inrush current controller and power distribution protection system Download PDFInfo
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- CN202019189U CN202019189U CN2010206867258U CN201020686725U CN202019189U CN 202019189 U CN202019189 U CN 202019189U CN 2010206867258 U CN2010206867258 U CN 2010206867258U CN 201020686725 U CN201020686725 U CN 201020686725U CN 202019189 U CN202019189 U CN 202019189U
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Abstract
The present utility model discloses an inrush current controller and a power distribution protection system. The inrush current controller comprises a one-chip microcomputer, a trip circuit for controlling high voltage AC circuit breaker opening, and a current transformer for sampling phase current. The current transformer for sampling phase current is connected with a current-detecting end of the one-chip microcomputer, and the trip circuit is connected with a trip control output end of the one-chip microcomputer. The power distribution protection system comprises a high voltage transformer and a high voltage AC circuit breaker provided with the inrush current controller. By getting rid of the traditional DC sampling and adopting AC sampling, the whole information of current can be obtained by the one-chip microcomputer, thus the sampling current can be correctly identified as inrush current or fault current, and a delay avoiding or opening instruction is given out. Moreover, even as mentioned in the background technology, under the circumstances that fault closing happens or a load side is provided with a multipath transformer or an inductive load, misoperation will also not happen.
Description
Technical field
The utility model belongs to the resist technology field of shoving, and is specifically related to a kind of shove controller and adopt this kind to shove power distribution protection system that controller forms that is applicable under the high-voltage alternating environment.
Background technology
High-voltage AC breaker plays crucial effect as the infrastructure device of power distribution protection to safety, the stable operation of electrical network.Reliability and selectivity all are one of four big basic demands of power distribution protection system, need realize than the higher equipment of the reliability index of electrical network own, so the reliability of circuit breaker is particularly important.The controller that shoves is the core component that circuit breaker is correctly finished function, and is therefore, particularly strict to the reliability requirement of the controller that shoves.
Shoving is the transformer harmonic current that excitation produces when initially powering on.Shove and have following characteristics:
(1), the magnetizing inrush current (abbreviation shoves) that certainly leads to because of the excitation process at initial powered on moment of transformer.
(2), the effective value that shoves is very big, can reach 8～10 times of rated current; But it is very fast to decay, and generally decays to 0.25～0.5 times of rated current after transformer powers on 0.5～1s.
(3), shove and contain very big aperiodic component of numerical value and higher harmonic components (mainly being secondary, quintuple harmonics).
The domestic controller that typically shoves adopts the direct current sampling, adopts " time expander method powers on " to dodge and shove, and starts time-delay after promptly controller works on power immediately and avoids " shoving ".The used controller that shoves itself can't really be discerned and shove in this method, but assert that controller powered on moment electrical network certain existence shove, and does not shove At All Other Times.This method had not both had scientific basis, had not met the electrical network truth yet.Following example explanation:
(1), the situation of fault combined floodgate
If when switch closed a floodgate, load-side is short circuit, the controller that the shoves this moment time-delay that powers on, switch does not trip.Will cause serious harm to electrical network.
(2), the situation of load-side band multichannel transformer or inductive load
For the electric network composition shown in the accompanying drawing 2, when having only transformer (1) to drop into, controller (C) can be dodged and shove by " time expander method powers on ".Back transformer (2) drops into simultaneously if power on, and generation is shoved equally, and the controller (C) that shoves this moment will shove and be considered as short trouble protected, and cause misoperation.Cause unnecessary power failure, such misoperation has destroyed the requirement of electric network protection selectivity.
In addition, do not drive the energy storage measuring ability in the existing controller that shoves, causing controller to be carried out when repeatedly threading off action can be because the not enough phenomenon do not fallen of taking off of capacitor self-energy, and then causes actual act delay time value to be far longer than the setting-up time value, brings harm to electrical network.
In addition, the existing controller that shoves adopts adjustable potentiometer calibration current parameter, and the problem of this method maximum is exactly, adjustable potentiometer in use resistance value can change, especially out of doors in the environment, current measurement is just inaccurate like this, often causes the circuit breaker misoperation or is failure to actuate.
The utility model content
First goal of the invention of the utility model provides a kind of real can identification shoving, and threads off and controls the controller that shoves comparatively reliably.
Second goal of the invention of the utility model provides that a kind of real identification is shoved and realization is shoved to be dodged, the fault-current protection function, and control power distribution protection system comparatively reliably threads off.
The technical scheme that realizes first purpose of the utility model is: a kind of controller that shoves comprises single-chip microcomputer, is used to control the trip circuit of high-voltage AC breaker separating brake and to the current transformer of phase current sampling; Described phase current sampling current transformer directly links to each other with the current detecting end of single-chip microcomputer, and trip circuit links to each other with the dropout control output end of single-chip microcomputer.
In the technique scheme, the current parameters of described single-chip microcomputer calibration control end is connected with calibration knob; The current coefficient of calibration is kept among the Flash of single-chip microcomputer with the form of numerical value.
In the technique scheme, also comprise the testing circuit that drives energy storage, the detection and the metering circuit of described driving energy storage comprise: storage capacitor C1, first resistance R 1, second resistance R 2, voltage stabilizing didoe D1 and optocoupler U1; First resistance R 1 and second resistance R, 2 series connection backs are in parallel with storage capacitor C1, the contact of first resistance R 1 and second resistance R 2 connects the negative electrode of voltage stabilizing didoe D1, the anode of the luminous tube among the anode of voltage stabilizing didoe D1 and the optocoupler U1 links to each other, the negative electrode of the luminous tube among the optocoupler U1 links to each other with the negative pole of storage capacitor C1, the grounded emitter of the photosensitive tube among the optocoupler U1, the collector electrode of the photosensitive tube among the optocoupler U1 links to each other with the single-chip microcomputer of circuit breaker.
In the technique scheme, the model of described single-chip microcomputer is MSP430F2122.
The technical scheme that realizes second purpose of the utility model is: a kind of power distribution protection system comprises high-tension transformer and has the high-voltage AC breaker of the controller that shoves; The described controller that shoves comprises single-chip microcomputer, be used to control the trip circuit of high-voltage AC breaker separating brake and to the current transformer of phase current sampling; Described phase current sampling current transformer directly links to each other with the current detecting end of single-chip microcomputer, and trip circuit links to each other with the dropout control output end of single-chip microcomputer.
In the technique scheme, described single-chip microcomputer adopts Adaptive Second harmonic wave algorithm to the AC signal of phase current sampling current transformer sampling, calculates the first-harmonic I in the sample waveform
A, second harmonic I
B, mean value I
C, and effective value I
D, and calculate following formula ratio: I
A/ I
BAnd I
C/ I
DIf I
A/ I
B〉=0.2 or I
C/ I
D〉=1 is judged as and shoves, and single-chip microcomputer is then delayed time and dodged.
In the technique scheme, the rated frequency of described high-voltage AC breaker is 50Hz, and rated voltage is 10kV; The rated voltage of primary winding is 10kV in the described high-tension transformer, and the rated voltage of secondary coil is 380V.
In the technique scheme, the described controller that shoves also comprises the LED that links to each other with the demonstration output of single-chip microcomputer; The current parameters calibration control end of described single-chip microcomputer is connected with calibration knob; The current coefficient of calibration is kept among the Flash of single-chip microcomputer with the form of numerical value.
In the technique scheme, also comprise the testing circuit that drives energy storage, the detection and the metering circuit of described driving energy storage comprise: storage capacitor C1, first resistance R 1, second resistance R 2, voltage stabilizing didoe D1 and optocoupler U1; First resistance R 1 and second resistance R, 2 series connection backs are in parallel with storage capacitor C1, the contact of first resistance R 1 and second resistance R 2 connects the negative electrode of voltage stabilizing didoe D1, the anode of the luminous tube among the anode of voltage stabilizing didoe D1 and the optocoupler U1 links to each other, the negative electrode of the luminous tube among the optocoupler U1 links to each other with the negative pole of storage capacitor C1, the grounded emitter of the photosensitive tube among the optocoupler U1, the collector electrode of the photosensitive tube among the optocoupler U1 links to each other with the single-chip microcomputer of circuit breaker.
In the technique scheme, the model of described single-chip microcomputer is MSP430F2122.
The utlity model has following advantage:
(1) the utility model has forgone the direct current sampling traditional, adopts to exchange sampling, and single-chip microcomputer can obtain the full detail (as waveform, phase place, amplitude) of electric current, for correct basis is established in the analysis of the later waveform that shoves.
(2) the utility model can identify correctly that sample rate current shoves or fault current, the fault that background technology is mentioned close a floodgate or situations such as load-side band multichannel transformer or inductive load under misoperation can not take place.
(3) the utlity model has the testing circuit that drives energy storage, in use, when the magnitude of voltage on the storage capacitor arrives a certain fixed value, give signal of single-chip microcomputer,, guaranteed the reliability of threading off and controlling for the action of single-chip microcomputer execute protection provides a foundation.In addition, single-chip microcomputer detects phase current in real time by current transformer, proportionate relationship according to real-time phase current, charging interval and charge volume, behind the slave controller electrification reset, begin to calculate the charge capacity of storage capacitor, electric weight up to storage capacitor satisfies the dropout requirement, puts flag bit, stops then calculating.During use, adopt two kinds of detection methods to judge simultaneously whether the magnitude of voltage on the storage capacitor arrives preset value, and any one method detects storage capacitor energy storage and finishes, think that then capacitance energy storage finishes.
(4) the utility model by the method for software intelligence computation, is used calibration Automatic Program calibration current parameter in use, and the current coefficient of calibration is kept among the Flash of single-chip microcomputer with the form of numerical value.This way parameter is accurate for a long time, has guaranteed the accuracy of measuring, thereby guarantees the reliability of long-term work.
Description of drawings
For the easier quilt of content of the present utility model is clearly understood, below the specific embodiment and in conjunction with the accompanying drawings of basis, the utility model is described in further detail, wherein
Fig. 1 is a kind of electrical block diagram of the controller that shoves in the utility model;
Fig. 2 is a kind of structural representation of power distribution protection system in the utility model;
Fig. 3 is the wave character figure that shoves that produces in the power distribution protection shown in Figure 2 system.
Embodiment
(embodiment 1, controller shoves)
Fig. 1 is a kind of electrical block diagram of the controller that shoves in the utility model, has shown a kind of embodiment of the controller that shoves in the utility model.
Present embodiment is a kind of controller that shoves that is used for high-voltage AC breaker, see shown in Figure 1ly, comprise single-chip microcomputer, be used to control trip circuit, current transformer, the LED that links to each other with the demonstration output of single-chip microcomputer and the testing circuit of described driving energy storage of high-voltage AC breaker separating brake phase current sampling; Described phase current sampling current transformer directly links to each other with the current detecting end of single-chip microcomputer, and trip circuit links to each other with the dropout control output end of single-chip microcomputer.
The current parameters calibration control end of described single-chip microcomputer is connected with calibration knob; The current coefficient of calibration is kept among the Flash of single-chip microcomputer with the form of numerical value.
The detection and the metering circuit of described driving energy storage comprise: storage capacitor C1, first resistance R 1, second resistance R 2, voltage stabilizing didoe D1 and optocoupler U1; First resistance R 1 and second resistance R, 2 series connection backs are in parallel with storage capacitor C1, the contact of first resistance R 1 and second resistance R 2 connects the negative electrode of voltage stabilizing didoe D1, the anode of the luminous tube among the anode of voltage stabilizing didoe D1 and the optocoupler U1 links to each other, the negative electrode of the luminous tube among the optocoupler U1 links to each other with the negative pole of storage capacitor C1, the grounded emitter of the photosensitive tube among the optocoupler U1, the collector electrode of the photosensitive tube among the optocoupler U1 links to each other with the single-chip microcomputer of circuit breaker
The model of the used single-chip microcomputer of present embodiment is MSP430F2122.
(embodiment 2, power distribution protection system)
Fig. 2 and Fig. 3 have shown a kind of embodiment of power distribution protection system in the utility model, and wherein Fig. 2 is a kind of structural representation of power distribution protection system in the utility model; Fig. 3 is the wave character figure that shoves that produces in the circuit shown in Figure 2.
Present embodiment is a kind of power distribution protection system that is used for high-voltage fence, sees Fig. 2 and Fig. 3, comprises two high-tension transformers and has the high-voltage AC breaker of the controller that shoves; The described controller that shoves comprises single-chip microcomputer, is used to control the trip circuit of high-voltage AC breaker separating brake, the current transformer to phase current sampling, LED and drive the testing circuit of energy storage; Described tripping mechanism comprises electromagnetic release and trip circuit; Described phase current sampling current transformer directly links to each other with the current detecting end of single-chip microcomputer, and trip circuit links to each other with the dropout control output end of single-chip microcomputer, and LED links to each other with the demonstration output of single-chip microcomputer.
The described controller that shoves is as the high-voltage AC breaker core component, is used for that it shoves or fault current according to exchanging the sampling current analysis and judgement; If fault current then sends the instruction of threading off immediately, high-voltage AC breaker is separating brake immediately; If shove, then time-delay is dodged.
The rated frequency of described high-voltage AC breaker is 50Hz, and rated voltage is 10kV; The rated voltage of primary winding is 10kV in the described high-tension transformer, and the rated voltage of secondary coil is 380V.
Described single-chip microcomputer adopts Adaptive Second harmonic wave algorithm to the AC signal of phase current sampling current transformer sampling, calculates the first-harmonic I in the sample waveform
A, second harmonic I
B, mean value I
C, and effective value I
D, and calculate following formula ratio: I
A/ I
BAnd I
C/ I
DIf I
A/ I
B〉=0.2 or I
C/ I
D〉=1 is judged as and shoves, and single-chip microcomputer is then delayed time and dodged.
The current parameters calibration control end of described single-chip microcomputer is connected with calibration knob, and the current coefficient of calibration is kept among the Flash of single-chip microcomputer with the form of numerical value.
The detection and the metering circuit of described driving energy storage comprise: storage capacitor C1, first resistance R 1, second resistance R 2, voltage stabilizing didoe D1 and optocoupler U1; First resistance R 1 and second resistance R, 2 series connection backs are in parallel with storage capacitor C1, the contact of first resistance R 1 and second resistance R 2 connects the negative electrode of voltage stabilizing didoe D1, the anode of the luminous tube among the anode of voltage stabilizing didoe D1 and the optocoupler U1 links to each other, the negative electrode of the luminous tube among the optocoupler U1 links to each other with the negative pole of storage capacitor C1, the grounded emitter of the photosensitive tube among the optocoupler U1, the collector electrode of the photosensitive tube among the optocoupler U1 links to each other with the single-chip microcomputer of circuit breaker.
The model of the used single-chip microcomputer of present embodiment is MSP430F2122.
The foregoing description 1 and embodiment 2 have the following advantages:
(1) the foregoing description 1 and embodiment 2 have forgone the direct current sampling traditional, adopt to exchange sampling, and single-chip microcomputer can obtain the full detail (as waveform, phase place, amplitude) of electric current, for correct basis is established in the analysis of the later waveform that shoves.
(2) the foregoing description 1 and embodiment 2 can identify correctly that sample rate current shoves or fault current, sending time-delay dodge or thread off separating brake instruction, though the fault that background technology is mentioned close a floodgate or situations such as load-side band multichannel transformer or inductive load under misoperation can not take place.
(3) the foregoing description 1 and embodiment 2 have detection and the metering circuit that drives energy storage; in use, when the magnitude of voltage on the storage capacitor arrives a certain fixed value, give signal of single-chip microcomputer; for the action of single-chip microcomputer execute protection provides a foundation, guaranteed the reliability of threading off and controlling.In addition, single-chip microcomputer detects phase current in real time by current transformer, proportionate relationship according to real-time phase current, charging interval and charge volume, behind the slave controller electrification reset, begin to calculate the charge capacity of storage capacitor, electric weight up to storage capacitor satisfies the dropout requirement, puts flag bit, stops then calculating.During use, adopt two kinds of detection methods to judge simultaneously whether the magnitude of voltage on the storage capacitor arrives preset value, and any one method detects storage capacitor energy storage and finishes, think that then capacitance energy storage finishes.
(4) the foregoing description 1 and embodiment 2 by the method for software intelligence computation, use calibration Automatic Program calibration current parameter in use, and the current coefficient of calibration is kept among the Flash of single-chip microcomputer with the form of numerical value.This way parameter is accurate for a long time, has guaranteed the accuracy of measuring, thereby guarantees the reliability of long-term work.
Obviously, the foregoing description only is for the utility model example clearly is described, and is not to be qualification to execution mode of the present utility model.For those of ordinary skill in the field, can also make other changes in different forms on the basis of the above description.Here need not also can't give exhaustive to all execution modes.And these belong to conspicuous variation or the change that spirit of the present utility model extended out and still are among the protection range of the present utility model.
Claims (10)
1. controller that shoves comprises single-chip microcomputer, is used to control the trip circuit of high-voltage AC breaker separating brake and to the current transformer of phase current sampling; It is characterized in that: described phase current sampling current transformer directly links to each other with the current detecting end of single-chip microcomputer, and trip circuit links to each other with the dropout control output end of single-chip microcomputer.
2. the controller that shoves according to claim 1 is characterized in that: the current parameters calibration control end of described single-chip microcomputer is connected with calibration knob; The current coefficient of calibration is kept among the Flash of single-chip microcomputer with the form of numerical value.
3. the controller that shoves according to claim 1, it is characterized in that: also comprise the testing circuit that drives energy storage, the detection and the metering circuit of described driving energy storage comprise: storage capacitor (C1), first resistance (R1), second resistance (R2), voltage stabilizing didoe (D1) and optocoupler (U1); First resistance (R1) and second resistance (R2) series connection back are in parallel with storage capacitor (C1), the contact of first resistance (R1) and second resistance (R2) connects the negative electrode of voltage stabilizing didoe (D1), the anode of the luminous tube in the anode of voltage stabilizing didoe (D1) and the optocoupler (U1) links to each other, the negative electrode of the luminous tube in the optocoupler (U1) links to each other with the negative pole of storage capacitor (C1), the grounded emitter of the photosensitive tube in the optocoupler (U1), the collector electrode of the photosensitive tube in the optocoupler (U1) links to each other with the single-chip microcomputer of circuit breaker.
4. according to the described controller that shoves of one of claim 1-3, it is characterized in that: the model of described single-chip microcomputer is MSP430F2122.
5. power distribution protection system comprises high-tension transformer and has the high-voltage AC breaker of the controller that shoves; It is characterized in that: the described controller that shoves comprises single-chip microcomputer, be used to control the trip circuit of high-voltage AC breaker separating brake and to the current transformer of phase current sampling; Described phase current sampling current transformer directly links to each other with the current detecting end of single-chip microcomputer, and trip circuit links to each other with the dropout control output end of single-chip microcomputer.
6. power distribution protection according to claim 5 system is characterized in that: described single-chip microcomputer adopts Adaptive Second harmonic wave algorithm to the AC signal of phase current sampling current transformer sampling, calculates the first-harmonic I in the sample waveform
A, second harmonic I
B, mean value I
C, and effective value I
D, and calculate following formula ratio: I
A/ I
BAnd I
C/ I
DIf I
A/ I
B〉=0.2 or I
C/ I
D〉=1 is judged as and shoves, and single-chip microcomputer is then delayed time and dodged.
7. power distribution protection according to claim 5 system, it is characterized in that: the rated frequency of described high-voltage AC breaker is 50Hz, rated voltage is 10kV; The rated voltage of primary winding is 10kV in the described high-tension transformer, and the rated voltage of inferior coil is 380V.
8. power distribution protection according to claim 5 system, it is characterized in that: the described controller that shoves also comprises the LED that links to each other with the demonstration output of single-chip microcomputer; The current parameters calibration control end of described single-chip microcomputer is connected with calibration knob; The current coefficient of calibration is kept among the Flash of single-chip microcomputer with the form of numerical value.
9. power distribution protection according to claim 5 system, it is characterized in that: also comprise the testing circuit that drives energy storage, the detection and the metering circuit of described driving energy storage comprise: storage capacitor (C1), first resistance (R1), second resistance (R2), voltage stabilizing didoe (D1) and optocoupler (U1); First resistance (R1) and second resistance (R2) series connection back are in parallel with storage capacitor (C1), the contact of first resistance (R1) and second resistance (R2) connects the negative electrode of voltage stabilizing didoe (D1), the anode of the luminous tube in the anode of voltage stabilizing didoe (D1) and the optocoupler (U1) links to each other, the negative electrode of the luminous tube in the optocoupler (U1) links to each other with the negative pole of storage capacitor (C1), the grounded emitter of the photosensitive tube in the optocoupler (U1), the collector electrode of the photosensitive tube in the optocoupler (U1) links to each other with the single-chip microcomputer of circuit breaker.
10. according to the described power distribution protection of one of claim 5-9 system, it is characterized in that: the model of described single-chip microcomputer is MSP430F2122.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010206867258U CN202019189U (en) | 2010-12-29 | 2010-12-29 | Inrush current controller and power distribution protection system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010206867258U CN202019189U (en) | 2010-12-29 | 2010-12-29 | Inrush current controller and power distribution protection system |
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| Publication Number | Publication Date |
|---|---|
| CN202019189U true CN202019189U (en) | 2011-10-26 |
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| CN2010206867258U Expired - Fee Related CN202019189U (en) | 2010-12-29 | 2010-12-29 | Inrush current controller and power distribution protection system |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102769267A (en) * | 2012-08-15 | 2012-11-07 | 王道连 | Intelligent flashy flow controller |
| CN112782575A (en) * | 2020-12-27 | 2021-05-11 | 常熟开关制造有限公司(原常熟开关厂） | Current measuring device for circuit breaker, maintenance and correction method of current measuring device and intelligent circuit breaker |
| CN112848953A (en) * | 2021-02-01 | 2021-05-28 | 无锡职业技术学院 | Electric vehicle charging control system |
-
2010
- 2010-12-29 CN CN2010206867258U patent/CN202019189U/en not_active Expired - Fee Related
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102769267A (en) * | 2012-08-15 | 2012-11-07 | 王道连 | Intelligent flashy flow controller |
| CN112782575A (en) * | 2020-12-27 | 2021-05-11 | 常熟开关制造有限公司(原常熟开关厂） | Current measuring device for circuit breaker, maintenance and correction method of current measuring device and intelligent circuit breaker |
| CN112848953A (en) * | 2021-02-01 | 2021-05-28 | 无锡职业技术学院 | Electric vehicle charging control system |
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| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20111026 Termination date: 20141229 |
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| EXPY | Termination of patent right or utility model |