CN105044575A - High-voltage direct-current power distribution insulation-against-ground monitoring device - Google Patents
High-voltage direct-current power distribution insulation-against-ground monitoring device Download PDFInfo
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Abstract
The invention discloses a high-voltage direct-current power distribution insulation-against-ground monitoring device. The high-voltage direct-current power distribution insulation-against-ground monitoring device includes an electric leakage signal acquisition unit which can acquire electric leakage signals based on a high-voltage direct-current power distribution insulation-against-ground part to be monitored, a single-chip microcomputer which processes the electric leakage signals which are obtained based on the electric leakage signal acquisition unit, and transmits intervention signals, and an output device which executes corresponding intervention operation based on the intervention signals transmitted by the single-chip microcomputer and under the control of the single-chip microcomputer. With the high-voltage direct-current power distribution insulation-against-ground monitoring device of the invention adopted, defects such as low work reliability, high maintenance difficulty and poor safety in the prior art can be eliminated, and therefore, the high-voltage direct-current power distribution insulation-against-ground monitoring device has the advantages of high work reliability, low maintenance difficulty and high safety.
Description
Technical field
The present invention relates to telecommunication circuit technical field, particularly, relate to a kind of high voltage direct current distribution insulation against ground supervisory device.
Background technology
Along with communication 240/336V DC power system is promoted on a large scale, applies and popularized, the effect of its reliability, economy and energy-conserving and environment-protective aspect gains universal acceptance.
Communication by 240/336V DC power system for communication power supply industry or new technology, its obvious difference with-48V DC communication power system is exactly DC bus is suspension system over the ground, and floating neutral system just needs real-time observation system DC bus insulation status over the ground, therefore need configuration insulating monitoring function.
For a long time, the working method of plus earth that what traditional-48V DC power-supply system adopted always is, when p-48V system dc power-supply system carries out Operation and Maintenance, because operating voltage is lower, when maintainer touches accumulator or negative pole, voltage is difficult to puncture human body resistance and forms electric current, electric shock accidents can not occur.And for 240/336V DC voltage, if by a pole ground connection, because voltage compare is high, when people touches a unearthed pole, shock current forms loop by the earth, shock hazard will be there is.
Realizing in process of the present invention, inventor finds at least to exist in prior art that functional reliability is low, maintenance difficulties large and the defect such as poor stability.
Summary of the invention
The object of the invention is to, for the problems referred to above, propose a kind of high voltage direct current distribution insulation against ground supervisory device, to realize the advantage that functional reliability is high, maintenance difficulties is little and security is good.
For achieving the above object, the technical solution used in the present invention is: a kind of high voltage direct current distribution insulation against ground supervisory device, comprise the electric leakage signal collecting unit that can gather electric leakage signal based on high voltage direct current distribution insulation against ground part to be supervised, can gather gained electric leakage signal based on described electric leakage signal collecting unit carry out processing and send the single-chip microcomputer of intervention signal, and the intervention signal that can send under the control of described single-chip microcomputer, based on single-chip microcomputer performs the output unit of corresponding intervention operation.
Further, described electric leakage signal collecting unit, comprises the multi-path choice module be connected with described single-chip microcomputer, and parallel arrange and respectively with n electricity leakage sensor of described multi-path choice model calling; N is natural number.
Further, described multi-path choice module, comprises the one-level MUX be connected with described single-chip microcomputer, and parallel arranges and m the secondary MUX be connected with described one-level MUX respectively;
Each secondary MUX is also connected with single-chip microcomputer, and n electricity leakage sensor is divided into m group, and often in group, each electricity leakage sensor connects with corresponding secondary MUX; M is the natural number being not more than n.
Further, between described one-level MUX and single-chip microcomputer, be also connected with the 2nd A/D analog to digital converter.
Further, described output unit, the resistance switching device between two splicing ears comprising the described single-chip microcomputer connected successively and photoelectrical coupler.
Further, described output unit, also comprises the output relay and/or communication chip and/or storer that link with described single-chip microcomputer respectively.
Further, between described resistance switching device and photoelectrical coupler, be also connected with an A/D analog to digital converter.
Further, described resistance switching device, comprises 240/336V straight-flow system, and is connected in parallel on the first resistance branch, the second resistance branch, the 3rd resistance branch and the information technoloy equipment at described 240/336V straight-flow system two ends.
Further, described first resistance branch, comprises and is connected to the first resistance R1 between described 240/336V straight-flow system two ends and the second resistance R2 in turn, the common end grounding of described first resistance R1 and the second resistance R2;
And/or,
Described second resistance branch, comprises the first K switch 1, the 3rd resistance R3, the 4th resistance R4 and second switch K2 that are connected in turn between described 240/336V straight-flow system two ends, the common end grounding of described 3rd resistance R3 and the 4th resistance R4;
And/or,
Described 3rd resistance branch, comprise the first prediction insulation against ground resistance Rx and the second prediction insulation against ground resistance Ry be connected in turn between described 240/336V straight-flow system two ends, the common end grounding of described first prediction insulation against ground resistance Rx and second prediction insulation against ground resistance Ry.
Further, by described first prediction insulation against ground resistance Rx and second prediction insulation against ground resistance Ry, calculate positive and negative bus insulation against ground resistance i.e. the first prediction insulation against ground resistance Rx and second prediction insulation against ground resistance Ry, computation process is as follows:
By the first K switch 1 and second switch K2 disjunction in turn, measure the first prediction insulation against ground resistance Rx both end voltage and positive pole voltage-to-ground V1 and the second prediction insulation against ground resistance Ry both end voltage and negative pole voltage-to-ground V2 respectively, then the first prediction insulation against ground resistance Rx and second prediction insulation against ground resistance Ry is calculated, when discovery first predicts that insulation against ground resistance Rx and second prediction insulation against ground resistance Ry is less than default warning value and namely sends alarm;
When the first K switch 1 close, second switch K2 disconnect time:
When the first K switch 1 disconnect, second switch K2 close time:
By more than simultaneous two equations, the first prediction insulation against ground resistance Rx and second prediction insulation against ground resistance Ry can be solved.
The high voltage direct current distribution insulation against ground supervisory device of various embodiments of the present invention, owing to comprising the electric leakage signal collecting unit that can gather electric leakage signal based on high voltage direct current distribution insulation against ground part to be supervised, can gather gained electric leakage signal based on electric leakage signal collecting unit carry out processing and send the single-chip microcomputer of intervention signal, and the intervention signal that can send under the control of single-chip microcomputer, based on single-chip microcomputer performs the output unit of corresponding intervention operation; Thus can overcome that functional reliability in prior art is low, the defect of the large and poor stability of maintenance difficulties, to realize the advantage that functional reliability is high, maintenance difficulties is little and security is good.
Other features and advantages of the present invention will be set forth in the following description, and, partly become apparent from instructions, or understand by implementing the present invention.
Below by drawings and Examples, technical scheme of the present invention is described in further detail.
Accompanying drawing explanation
Accompanying drawing is used to provide a further understanding of the present invention, and forms a part for instructions, together with embodiments of the present invention for explaining the present invention, is not construed as limiting the invention.In the accompanying drawings:
Fig. 1 is the principle of work schematic diagram of high voltage direct current distribution insulation against ground supervisory device of the present invention;
Fig. 2 is the principle of work schematic diagram of resistance switching device in the present invention;
Fig. 3 is the principle of work schematic diagram of branch road leakage current test method in the present invention.
Embodiment
Below in conjunction with accompanying drawing, the preferred embodiments of the present invention are described, should be appreciated that preferred embodiment described herein is only for instruction and explanation of the present invention, is not intended to limit the present invention.
According to the embodiment of the present invention, as shown in Figure 1-Figure 3, a kind of high voltage direct current distribution insulation against ground supervisory device is provided.Here, insulating monitoring, refers in DC power-supply system, detects with the insulating property on ground direct current output, judges whether earth fault or insulating property reduction occur, and, send alarm signal when breaking down or insulating property are deteriorated.
The high voltage direct current distribution insulation against ground supervisory device of technical solution of the present invention, be made up of single-chip microcomputer, storer, resistance switching device, MUX, A/D converter, leakage current sensor, photoelectrical coupler, output relay and Intelligent communication module etc., be mainly used in communications equipment room, base station and data center machine room 240/336V direct current row cabinet, calculate high voltage direct current row cabinet inlet wire positive pole and negative pole insulation against ground resistance for gathering, exporting branch road leakage current, exporting the parameters such as branch road insulation against ground resistance.Whether good in order to monitor high voltage direct current power distribution insulation against ground situation.
The technical solution used in the present invention, specifically: 240/336V DC distribution insulation against ground supervisory device, is made up of single-chip microcomputer, storer, resistance switching device, MUX, A/D converter, leakage current sensor, photoelectrical coupler, output relay and Intelligent communication module etc.Technical scheme of the present invention has following characteristics:
(1) the mode that the calculating of insulation against ground resistance adopts switching resistance detection method and leakage current test method to combine realizes.The insulation against ground of main road bus adopts voltage detecting and switching resistance to calculate, and branch road insulation against ground adopts voltage detecting and leakage current method to calculate.This had both remained the advantages such as the structure of balance bridge resistance detection is simple, fast response time, the advantage that the insulation fault combining again leakage current test method is accurately located.
(2) adopt two-stage MUX to carry out detection and localization, significantly increase detection way.
(3) resistance switching mimic channel and digital circuit are completely isolated by photoelectrical coupler, avoid the impact of digital circuit on system insulation.
The general frame of technical solution of the present invention as shown in Figure 1,240/336V DC distribution insulation against ground supervisory device, is made up of single-chip microcomputer, storer, resistance switching device, MUX, A/D converter, leakage current sensor, photoelectrical coupler, output relay and Intelligent communication module etc.
MUX adopts ADG1308 multiway analog switch chip, and this chip is 8 passage two-way choice chips, and in the apparatus, adopts the design of two-stage multi-path choice, maximum can gating 32 road branch road leakage current sensor signal.
Resistance switching device: the voltage-to-ground of the positive and negative DC bus of insulating monitoring system Real-Time Monitoring, calculates positive and negative bus insulation against ground resistance by voltage-to-ground.Busbar voltage and bus resistance to earth adopt resistance switching device to realize, and principle as shown in Figure 2.
By K1 and K2 disjunction in turn, measure positive pole voltage-to-ground V1 and negative pole voltage-to-ground V2 respectively.Then calculate Rx and Ry, namely send alarm when discovery Rx and Ry is less than default warning value.
When K1 closes, when K2 disconnects:
When K1 disconnects, when K2 closes:
By more than simultaneous two equations, Rx and Ry can be solved.
Branch road leakage current test method, see Fig. 3.
Current transformer (CT) is arranged on each branch road, and both positive and negative polarity all passes same current transformer.Under normal circumstances, because both positive and negative polarity is equal, the resultant current therefore flowing through this synthesis mutual inductor is zero.When the branch road of mutual inductor rear end there occurs earth fault or insulativity change, outlet leakage current over the ground, then the electric current flowing through this mutual inductor occurs uneven, can judge that this branch road there occurs earth fault.
By measuring branch current, in conjunction with the both positive and negative polarity voltage before and after bus switching resistance, the insulation against ground resistance value of this branch road can be calculated.
To sum up, compared with prior art, technical scheme of the present invention, the beneficial effect that at least can reach is:
(1) insulating monitoring function mainly comprises two aspects: be the insulativity decline in Timeliness coverage system dc loop and fault on the one hand; To occurring that insulativity declines and location of fault positions on the other hand.
(2) insulating monitoring mainly detects insulation against ground resistance in direct current power supply loop and distributed capacitance.
(3) use in 240V DC power-supply system in communication, when earth fault appears in DC loop or insulativity declines, marking current over the ground can be produced in trouble spot, have insulating monitoring system directly or indirectly to measure corresponding resistance to earth and insulating resistance value.When insulating resistance value exceedes the setting valve of systemic presupposition, type insulation monitoring system produces action message, sends corresponding alarm signal.
Last it is noted that the foregoing is only the preferred embodiments of the present invention, be not limited to the present invention, although with reference to previous embodiment to invention has been detailed description, for a person skilled in the art, it still can be modified to the technical scheme described in foregoing embodiments, or carries out equivalent replacement to wherein portion of techniques feature.Within the spirit and principles in the present invention all, any amendment done, equivalent replacement, improvement etc., all should be included within protection scope of the present invention.
Claims (10)
1. a high voltage direct current distribution insulation against ground supervisory device, it is characterized in that, comprise the electric leakage signal collecting unit that can gather electric leakage signal based on high voltage direct current distribution insulation against ground part to be supervised, can gather gained electric leakage signal based on described electric leakage signal collecting unit carry out processing and send the single-chip microcomputer of intervention signal, and the intervention signal that can send under the control of described single-chip microcomputer, based on single-chip microcomputer performs the output unit of corresponding intervention operation.
2. high voltage direct current distribution insulation against ground supervisory device according to claim 1, it is characterized in that, described electric leakage signal collecting unit, comprises the multi-path choice module be connected with described single-chip microcomputer, and parallel arrange and respectively with n electricity leakage sensor of described multi-path choice model calling; N is natural number.
3. high voltage direct current distribution insulation against ground supervisory device according to claim 2, it is characterized in that, described multi-path choice module, comprise the one-level MUX be connected with described single-chip microcomputer, and parallel to arrange and m the secondary MUX be connected with described one-level MUX respectively;
Each secondary MUX is also connected with single-chip microcomputer, and n electricity leakage sensor is divided into m group, and often in group, each electricity leakage sensor connects with corresponding secondary MUX; M is the natural number being not more than n.
4. high voltage direct current distribution insulation against ground supervisory device according to claim 3, is characterized in that, between described one-level MUX and single-chip microcomputer, is also connected with the 2nd A/D analog to digital converter.
5. the high voltage direct current distribution insulation against ground supervisory device according to any one of claim 1-4, is characterized in that, described output unit, the resistance switching device between two splicing ears comprising the described single-chip microcomputer connected successively and photoelectrical coupler.
6. high voltage direct current distribution insulation against ground supervisory device according to claim 5, is characterized in that, described output unit, also comprises the output relay and/or communication chip and/or storer that link with described single-chip microcomputer respectively.
7. high voltage direct current distribution insulation against ground supervisory device according to claim 5, is characterized in that, between described resistance switching device and photoelectrical coupler, is also connected with an A/D analog to digital converter.
8. high voltage direct current distribution insulation against ground supervisory device according to claim 5, it is characterized in that, described resistance switching device, comprise 240/336V straight-flow system, and be connected in parallel on the first resistance branch, the second resistance branch, the 3rd resistance branch and the information technoloy equipment at described 240/336V straight-flow system two ends.
9. high voltage direct current distribution insulation against ground supervisory device according to claim 8, it is characterized in that, described first resistance branch, comprise and be connected to the first resistance R1 between described 240/336V straight-flow system two ends and the second resistance R2 in turn, the common end grounding of described first resistance R1 and the second resistance R2;
And/or,
Described second resistance branch, comprises the first K switch 1, the 3rd resistance R3, the 4th resistance R4 and second switch K2 that are connected in turn between described 240/336V straight-flow system two ends, the common end grounding of described 3rd resistance R3 and the 4th resistance R4;
And/or,
Described 3rd resistance branch, comprise the first prediction insulation against ground resistance Rx and the second prediction insulation against ground resistance Ry be connected in turn between described 240/336V straight-flow system two ends, the common end grounding of described first prediction insulation against ground resistance Rx and second prediction insulation against ground resistance Ry.
10. high voltage direct current distribution insulation against ground supervisory device according to claim 9, it is characterized in that, by described first prediction insulation against ground resistance Rx and second prediction insulation against ground resistance Ry, calculate positive and negative bus insulation against ground resistance i.e. the first prediction insulation against ground resistance Rx and second prediction insulation against ground resistance Ry, computation process is as follows:
By the first K switch 1 and second switch K2 disjunction in turn, measure the first prediction insulation against ground resistance Rx both end voltage and positive pole voltage-to-ground V1 and the second prediction insulation against ground resistance Ry both end voltage and negative pole voltage-to-ground V2 respectively, then the first prediction insulation against ground resistance Rx and second prediction insulation against ground resistance Ry is calculated, when discovery first predicts that insulation against ground resistance Rx and second prediction insulation against ground resistance Ry is less than default warning value and namely sends alarm;
When the first K switch 1 close, second switch K2 disconnect time:
When the first K switch 1 disconnect, second switch K2 close time:
By more than simultaneous two equations, the first prediction insulation against ground resistance Rx and second prediction insulation against ground resistance Ry can be solved.
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Cited By (6)
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| CN105277840A (en) * | 2015-11-18 | 2016-01-27 | 国网山东省电力公司莱芜供电公司 | Multi-line electric leakage synchronous detection device of 220V alternating current lines |
| CN105607520A (en) * | 2016-02-19 | 2016-05-25 | 北京空间飞行器总体设计部 | Remote measurement acquisition control device for general extensible spacecraft |
| CN106054048A (en) * | 2016-07-21 | 2016-10-26 | 兰州海红技术股份有限公司 | Direct current 240/336V master control device |
| CN106483422A (en) * | 2016-11-30 | 2017-03-08 | 国网江苏省电力公司连云港供电公司 | A kind of DC grounding monitor instrument |
| CN106646079A (en) * | 2016-11-30 | 2017-05-10 | 国网江苏省电力公司连云港供电公司 | Online direct-current grounding monitoring system for power distribution automation terminal |
| CN116148538A (en) * | 2023-04-19 | 2023-05-23 | 深之蓝海洋科技股份有限公司 | Direct-current high-voltage insulation detection system and detection method |
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