CN102288863A - Device and method for detecting harmful electric arc in low-voltage power-supply system - Google Patents
Device and method for detecting harmful electric arc in low-voltage power-supply system Download PDFInfo
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- CN102288863A CN102288863A CN2011102068429A CN201110206842A CN102288863A CN 102288863 A CN102288863 A CN 102288863A CN 2011102068429 A CN2011102068429 A CN 2011102068429A CN 201110206842 A CN201110206842 A CN 201110206842A CN 102288863 A CN102288863 A CN 102288863A
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Abstract
The invention relates to a device for detecting harmful electric arc in a low-voltage power-supply system, which comprises a photo sensor and a non-contact temperature sensor which are sensitive to electric arc wavelengths and are arranged in the positions of conductor joints, a terminal row and a terminal box in the low-voltage power-supply system, and a microprocessor with judging, displaying and alarming functions, wherein various normal electric arc voltage waveforms are stored in the microprocessor, and the photo sensor and the non-contact temperature sensor are both communicated with the microprocessor. The invention has the beneficial effects that whether harmful electric arc exists in a circuit can be accurately judged, simultaneously the happening point of the harmful electric arc can be accurately positioned, and technical staff can be guided to eliminate the harmful electric arc in time, so electrical fire can be prevented.
Description
Technical field
The present invention relates to the low-voltage electrical technical field, relate in particular to the sniffer and the method for the harmful electric arc of a kind of low-voltage power supply system.
Background technology
Through long-term practice and serious analysis, positions such as the joint of the lead of discovery low-voltage power supply system inside, connection terminal, terminal box come in contact bad fault easily, and then cause electric arc, and finally may cause electrical fire by these electric arcs, so these electric arcs are called " harmful electric arc ", and the motor of the charged brush of operate as normal, switch, socket etc. locate also to have the generation of electric arc in the circuit, and these electric arcs can not cause electrical fire, therefore are called on " harmless electric arc ".We will these key points in supply line detect " harmful electric arc ", and in time locate and report to the police, and eliminate the hidden danger of electrical fire, then will not react harmless electric arc.
Existing Chinese utility model patent ZL200920352318.0 " electric system is harmful to the Electric arc monitoring device ", whether the wide spectrum radiowave that its principle only relies on the fluctuation of monitoring voltage, electric current and electric arc to produce is measured electric arc and is taken place, its detection principle is too simple, can't distinguish harmful and harmless electric arc, and the position that can't take place electric arc exactly positions, and therefore lacks practical value.The main hazard of harmful electric arc is to occur in low-voltage distribution system inside, and the position that produces is generally all more hidden, is not easy to be found by the people, so can not in time get rid of.When harmful electric arc increases gradually, develop near the combustible of a certain moment may igniting, thereby cause electrical fire.
Up to the present, the method that does not also have discovery in low-voltage power supply system, the position of harmful electric arc and generation thereof effectively to be monitored, generally can only judge in electric system inside whether have harmful electric arc with simple method, its method all is to measure indirectly by voltage in the test lead or electric current.Therefore, in low-voltage power supply system to the generation and the accurate in locating of monitoring harmful electric arc and prevent that aspect such as false alarm from providing effective solution and technology necessary.
Summary of the invention
The detection method that the purpose of this invention is to provide the harmful electric arc of a kind of low-voltage power supply system is harmful to electric arc and detects the problem that still can't accurately locate harmful electric arc to solve current the detection in low-voltage power supply system inside.
The objective of the invention is to be achieved through the following technical solutions:
The sniffer of the harmful electric arc of a kind of low-voltage power supply system, comprise: optical sensor and the non-contact temperature sensor that are installed in the positions such as wire joining, terminal row and terminal box of described low-voltage power supply system inside the electric arc wavelength sensitive, and microprocessor and described microprocessor stores with judgement, demonstration and warning function have multiple normal arc voltage waveform, and described optical sensor all is connected with described microprocessor communication with non-contact temperature sensor.
Described optical sensor and non-contact temperature sensor all have and the corresponding geocoding in its position.
The detection method of the harmful electric arc of a kind of low-voltage power supply system may further comprise the steps:
At optical sensor and the non-contact temperature sensor of the positions such as wire joining, terminal row and terminal box of low-voltage power supply system inside installation to the electric arc wavelength sensitive;
The microprocessor that communicates to connect with described optical sensor and non-contact temperature sensor is provided, and described microprocessor stores has multiple normal arc voltage waveform and has judgement, demonstration and warning function;
Be provided with and the described optical sensor of positions such as described wire joining, terminal row and terminal box and the corresponding geocoding in position of contactless temperature propagated sensation sensor;
Utilize optical sensor to measure arc light spectrum and the voltage in the measurement lead or the electric current variation of described position, and the temperature of utilizing non-contact temperature sensor to carry out each wire joining, terminal row and the terminal box position of geocoding is in advance monitored; And
When the temperature of the position of finding a certain geocoding on average raises 20 ℃ or above and possess voltage or electric current change condition simultaneously and show when having produced arc optical signal than environment temperature, the parameter of the arc voltage waveform of described position is sent in the microprocessor, compare with the various normal arc voltage waveform data of storing in the described database, after judgement is defined as harmful electric arc, send warning message, show the geocoding of harmful electric arc origination point simultaneously.
Described normal arc comprises: electric arc the when electric arc during brushed motor work, the electric arc when switch opens and closes, the electric arc when attaching plug is pegged graft and incandescent lamp screw in lamp socket or the like.
The temperature range that described non-contact temperature sensor is surveyed is 0-100 ℃, and when temperature was 50 ℃, its error was ± 1 ℃; When room temperature is 0 ℃-50 ℃, at airtight substantially 1000cm
3Can survey 20 ℃ of-50 ℃ of temperature rises in the volume.
Described optical sensor is to the electric arc arc light sensitivity of 398-457nm wavelength, because the arc light of electric arc has fixing spectrum and wavelength, according to surveying and determination, its wavelength coverage is greatly about 398-457nm, simultaneously the load both end voltage at the lead that harmful electric arc takes place has extremely unsettled characteristics, so the variation that utilizes optical sensor to measure the voltage at the arc light spectrum of monitoring location and sensing lead lead two ends at monitoring location just can tentatively judge whether to exist harmful electric arc at load two ends; Just can tentatively judge the harmful electric arc that is connected in the lead by the arc light spectrum that utilizes optical sensor to measure this location point at monitoring location with the electrorheological law of measuring in the lead.
Beneficial effect of the present invention is: whether the present invention exists harmful electric arc in the decision circuitry more exactly, can accurately locate harmful electric arc origination point simultaneously, can the bootstrap technique personnel in time get rid of harmful electric arc, just can prevent the generation of electrical fire; Can distinguish harmful electric arc and harmless electric arc effectively, because harmless electric arc all occurs in positions such as motor brush, socket, switch contact, and harmful electric arc generally all occurs in positions such as wire joining, terminal row, terminal box, by monitoring to above ad-hoc location, to compare with the harmless arc waveform data that are stored in advance in the arc waveform storehouse later on monitoring electric arc simultaneously, can differentiate, distinguish harmful and harmless electric arc, prevent false alarm.
Description of drawings
With reference to the accompanying drawings the present invention is described in further detail below.
Fig. 1 is the sniffer structured flowchart of the harmful electric arc of the described low-voltage power supply system of the embodiment of the invention;
Fig. 2 is the sniffer principle of work block diagram of the harmful electric arc of the described low-voltage power supply system of the embodiment of the invention;
Fig. 3 is the workflow diagram of the detection method of the harmful electric arc of the described low-voltage power supply system of the embodiment of the invention.
Among Fig. 2: 1, current transformer; 2, ac and dc current translation circuit; 3, combined-voltage conversion; 4, light sensation device; 5, contactless heat detector spare; 6, amplification and A/D translation circuit; 7, amplification and A/D conversion; 8, opto-electronic conversion; 9, amplification and A/D conversion; 10, amplification and A/D conversion; 11, micro-processor interface circuit (MCU); 12, warning circuit; 13, warning address display circuit; 14, memory circuit; 15, power supply; 16, normal arc waveform database.
Embodiment
As shown in Figure 1, the sniffer of the harmful electric arc of the described low-voltage power supply system of the embodiment of the invention comprises the optical sensor of current measurement circuit, tension measuring circuit, band geocoding and contactless heat detector spare, with electric loading and microprocessor etc. with judgement, demonstration and warning function, described microprocessor stores has multiple normal arc voltage waveform, and described optical sensor all is connected with described microprocessor communication with non-contact temperature sensor.A plurality of sniffers can be installed in low-voltage power supply system monitors with the harmful electric arc to low-voltage power supply system inside, can produce the characteristics of high temperature when utilizing electric arc to take place, the warm propagated sensation sensor that adopts the non-contact high-sensitivity temperature sensing device to form is monitored the temperature of each monitoring point such as each wire joining that carries out geocoding in advance, the terminal row that connects lead and terminal box, through test of many times, in distance 5-10mm closed environment, the temperature that exceeds than surrounding room temperature is called temperature rise, and limit of temperature rise is approximately 20 ℃-50 ℃.Providing limit of temperature rise mainly is the error that uncertainty produced of getting rid of distance between temperature sensing device and the electric arc.Judge through thermometric, when the temperature of the monitoring point of finding a certain coded address on average raises 20 ℃ or when above than environment temperature, possess voltage or electric current change condition simultaneously and produced arc optical signal, then the parameter of the arc voltage waveform of above monitoring point is delivered in the microprocessor (MCU), compare with the various normal arc voltage waveform data of storing in the database, after judgement is defined as harmful electric arc, send warning message, the geocoding that shows harmful electric arc origination point simultaneously, remind the monitor staff in time to handle, avoid the generation of electrical fire.
As shown in Figure 2, measure series current and pick up current value, become d. c. voltage signal, again through amplifying and A/D conversion 6 is converted to digital signal and delivers in the MCU microprocessor 11 through ac and dc current translation circuit 2 by mutual inductor 1; Voltage signal 3 becomes after the direct current signal through ac-dc conversion, again through amplifying and A/D conversion 7 becomes digital signal and delivers in the MCU microprocessor 11; Optical sensor 4 is transmitted to the electric arc arc optical signal in the opto-electronic conversion 8, and the arc optical signal of certain arc wave band is converted to electric signal, and this signal process amplification and A/D conversion 10 become digital signal and deliver to later in the MCU microprocessor 11.Accurate more and reliable in order to make to the monitoring of electric arc, also be provided with the temperature monitoring of 5 pairs of monitoring points of contactless heat detector spare, because electric arc can make the temperature in the little space raise on every side, contactless temp probe the temperature signal of monitoring point through amplifying and A/D conversion 9 becomes digital signal and passes to later in the MCU microprocessor 11, if there is electric arc in the circuit, but the temperature of electric arc origination point does not also rise, can think temporarily to be safe from danger, proceed the arc detection process of next address.If the condition that electric arc takes place all satisfies, the temperature of monitoring point also raises simultaneously, will compare the information of the electric arc that monitors with the normal arc information of normal arc database 16 the insides, when finding that the two is inequality, can confirm that the electric arc that monitors is harmful electric arc, sends warning at once; If the electric arc that discovery monitors is identical with the waveform in the arc waveform storehouse, explanation is harmless electric arc, need not report to the police, and this is effective ways of distinguishing harmful and harmless electric arc, also is another characteristics of the present invention.Warning message is reported to the police by microprocessor driven warning circuit 12, and at warning address display circuit 13 display alarm particular locations, simultaneously warning message is stored in the memory circuit 14.Power supply 15 is supplied with the complete machine energy.
As shown in Figure 3, after arc detection began, the monitoring address was made as 0, and the address adds 1, check at first whether the sensor devices that is positioned at address 1 has arc optical signal, if no, then the address adds 1 continuation inspection, circulates, if being checked through last address does not all have always, then the return address 0, continues circulation, until being checked through the discovery arc optical signal; Check then and have or not voltage fluctuation signal, if have, then carry out the signal that next step inspection has or not temperature to raise, if have, then the waveform with the normal arc database compares, if waveform is identical, explanation is harmless electric arc, automatically the monitoring address is added 1 detection of proceeding next monitoring point, if different with normal arc waveform, explanation is harmful electric arc, shows that the particular location of harmful electric arc takes place for harmful electric arc alerting signal and explicit address coded representation, whether after this need to check is last address, if last address then needs to turn back to address 0, the next circulation that starts anew is if not last address, then the address adds 1, continues the monitoring of next monitoring point; If there is not voltage fluctuation signal, then check to have or not the current fluctuation signal, if the current fluctuation signal is arranged, then further check to have or not temperature to raise, if when having temperature rising and temperature rise to surpass 20 ℃, if comparison normal arc waveform is identical, do not report to the police, if different, then explicit address and warning; If also no current fluctuation, then the address adds 1, continues above cyclic process.When the condition of electric arc satisfied substantially, but temperature does not also raise, and can not confirm that harmful electric arc takes place, and needs the address to add 1 and continues the detection of next monitoring point.
Positions such as the joint in the lead of low-voltage power supply system, connection terminal, owing to work long hours, contact resistance at the contact place strengthens gradually, the loss of this point is strengthened simultaneously, the increase of heat can make oxidation further aggravate, the result of vicious cycle can at a time produce the instability that loose contact causes electric current in this point, and interrupted connection will produce electric arc.These positions are made as the monitoring point, and it is carried out geocoding, the sensor devices to the arc spectrum sensitivity is set in these monitoring points simultaneously, when electric arc takes place, can detect the spectrum of the arclight of specific band.Unsettled electric current and electric arc arc optical signal are transferred in the detection circuit simultaneously, add the temperature survey to this point, have increased accuracy and the reliability judged, and this also is characteristics of the present invention.
Claims (9)
1. the sniffer of the harmful electric arc of a low-voltage power supply system is characterized in that it comprises:
Be installed in the optical sensor and the non-contact temperature sensor to the electric arc wavelength sensitive of wire joining, terminal row and the terminal box position of described low-voltage power supply system inside, and
Microprocessor and described microprocessor stores with judgement, demonstration and warning function have multiple normal arc voltage waveform, and described optical sensor all is connected with described microprocessor communication with non-contact temperature sensor.
2. the sniffer of the harmful electric arc of low-voltage power supply system as claimed in claim 1, it is characterized in that: described optical sensor is to the electric arc arc light sensitivity of 398-457nm wavelength.
3. the sniffer of the harmful electric arc of low-voltage power supply system as claimed in claim 2, it is characterized in that: described optical sensor and non-contact temperature sensor all have and the corresponding geocoding in its position.
4. as the sniffer of the harmful electric arc of each described low-voltage power supply system of claim 1-3, it is characterized in that: the temperature range that described non-contact temperature sensor is surveyed is 0-100 ℃, and when temperature was 50 ℃, its error was ± 1 ℃; When room temperature is 0 ℃-50 ℃, at airtight substantially 1000cm
3Can survey 20 ℃ of-50 ℃ of temperature rises in the volume.
5. be harmful to the sniffer of electric arc as each described low-voltage power supply system of claim 1-3, it is characterized in that described normal arc comprises: the electric arc the when electric arc during brushed motor work, the electric arc when switch opens and closes, the electric arc when attaching plug is pegged graft and incandescent lamp screw in lamp socket.
6. the detection method of the harmful electric arc of low-voltage power supply system is characterized in that, may further comprise the steps:
Optical sensor and non-contact temperature sensor to the electric arc wavelength sensitive are installed in the wire joining of low-voltage power supply system inside, terminal row and terminal box position;
The microprocessor that communicates to connect with described optical sensor and non-contact temperature sensor is provided, and described microprocessor stores has multiple normal arc voltage waveform and has judgement, demonstration and warning function;
Be provided with and described wire joining, terminal row and the described optical sensor of terminal box position and the corresponding geocoding in position of contactless temperature propagated sensation sensor;
Utilize optical sensor to measure arc light spectrum and the voltage in the measurement lead or the electric current variation of described position, and the temperature of utilizing non-contact temperature sensor to carry out each wire joining, terminal row and the terminal box position of geocoding is in advance monitored; And
When the temperature of the position of finding a certain geocoding on average raises 20 ℃ or above and possess voltage or electric current change condition simultaneously and show when having produced arc optical signal than environment temperature, the parameter of the arc voltage waveform of described position is sent in the microprocessor, compare with the various normal arc voltage waveform data of storing in the described database, after judgement is defined as harmful electric arc, send warning message, show the geocoding of harmful electric arc origination point simultaneously.
7. the detection method of the harmful electric arc of low-voltage power supply system as claimed in claim 6, it is characterized in that described normal arc comprises: the electric arc the when electric arc during brushed motor work, the electric arc when switch opens and closes, the electric arc when attaching plug is pegged graft and incandescent lamp screw in lamp socket.
8. the detection method of the harmful electric arc of low-voltage power supply system as claimed in claim 7 is characterized in that: the temperature range that described non-contact temperature sensor is surveyed is 0-100 ℃, and when temperature was 50 ℃, its error was ± 1 ℃; When room temperature is 0 ℃-50 ℃, at airtight substantially 1000cm
3Can survey 20 ℃ of-50 ℃ of temperature rises in the volume.
9. as the detection method of the harmful electric arc of each described low-voltage power supply system of claim 6-8, it is characterized in that: described optical sensor is to the electric arc arc light sensitivity of 398-457nm wavelength.
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Cited By (7)
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| CN103336223A (en) * | 2013-06-14 | 2013-10-02 | 上海叠泉信息科技有限公司 | Fault arc detecting and positioning system and method |
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| CN104180477A (en) * | 2014-08-15 | 2014-12-03 | 珠海格力电器股份有限公司 | Air conditioning system control method and air conditioning system |
| CN104360205A (en) * | 2014-12-01 | 2015-02-18 | 河北工业大学 | Cascaded arc fault detection method and special device for cascaded arc fault detection method |
| CN110308377A (en) * | 2019-07-23 | 2019-10-08 | 南京航空航天大学 | A kind of arc method for measuring for more electric aircraft DC systems |
| CN112363070A (en) * | 2021-01-14 | 2021-02-12 | 江苏固德威电源科技股份有限公司 | Battery arc discharge detection method and device and battery energy storage system |
| CN115407169A (en) * | 2022-10-28 | 2022-11-29 | 光子(深圳)精密科技有限公司 | Optical sensor and system for detecting switch cabinet flash arc |
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Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN112363070A (en) * | 2021-01-14 | 2021-02-12 | 江苏固德威电源科技股份有限公司 | Battery arc discharge detection method and device and battery energy storage system |
| CN112363070B (en) * | 2021-01-14 | 2021-06-22 | 江苏固德威电源科技股份有限公司 | Battery arc discharge detection method and device and battery energy storage system |
| CN115407169A (en) * | 2022-10-28 | 2022-11-29 | 光子(深圳)精密科技有限公司 | Optical sensor and system for detecting switch cabinet flash arc |
| CN115407169B (en) * | 2022-10-28 | 2023-02-10 | 光子(深圳)精密科技有限公司 | Optical sensor and system for detecting switch cabinet flash arc |
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Application publication date: 20111221 |