CN103018572A - Photovoltaic grid-connected inverter insulation resistance monitoring circuit - Google Patents
Photovoltaic grid-connected inverter insulation resistance monitoring circuit Download PDFInfo
- Publication number
- CN103018572A CN103018572A CN2012105584490A CN201210558449A CN103018572A CN 103018572 A CN103018572 A CN 103018572A CN 2012105584490 A CN2012105584490 A CN 2012105584490A CN 201210558449 A CN201210558449 A CN 201210558449A CN 103018572 A CN103018572 A CN 103018572A
- Authority
- CN
- China
- Prior art keywords
- bus
- isolation
- positive
- negative
- optical couplers
- 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.)
- Pending
Links
Images
Landscapes
- Inverter Devices (AREA)
Abstract
The invention discloses a photovoltaic grid-connected inverter insulation resistance monitoring circuit which comprises a resistor string, a bidirectional TVS (transient voltage suppressors) tube and two isolation optical couplers. A plurality of resistors are connected in series to form the resistor string, two ends of the resistor string are connected at a positive end and a negative end of a direct current bus of an inverter respectively, primary sides of the two isolation optical couplers are reversely connected in parallel and are connected in parallel with the bidirectional TVS tube, a wire led out from the middle of the resistor string is connected with the primary sides of the two isolation optical couplers and is grounded after penetrating through the optical couplers, resistance values from a positive bus and a negative bus to a wire leading-out point are different, collecting electrodes of secondary sides of the two isolation optical couplers are respectively connected with a control power supply, and emitting electrodes of the secondary sides of the two isolation optical couplers are respectively connected with a 0V end of the control power supply through current-limiting resistors. The monitoring circuit can reliably detect the conditions that the ground insulation resistance of the positive bus does not meet requirements, the ground insulation resistance of the negative bus does not meet requirements and the ground insulation resistances of the positive bus and the negative bus simultaneously do not meet requirements, safety of products is enhanced, and corresponding cost is reduced.
Description
Technical field
The present invention relates to a kind of supervisory circuit, particularly the supervisory circuit of the insulation impedance between photovoltaic DC-to-AC converter equipment and the ground.
Background technology
Photovoltaic array is installed on ground by the support large tracts of land usually, because variation or the fortuitous event of air conditions, occasional causes its positive and negative bus insulation against ground impedance not satisfy the safety requirement, may produce injury to the staff.But can there be following problem in some detection modes at present: this series products is generally the import accessory, so price is higher, accounts for about 2% of inversion holistic cost.And domestic inverter producer self-developing insulation impedance checkout equipment; usually can't detect in the time of can existing positive and negative bus insulation against ground impedance not meet the demands simultaneously; thereby cause the security feature of photovoltaic DC-to-AC converter can not arrive related request, also affect the export trade of domestic inverter simultaneously.Some schemes are not isolated main circuit and control circuit at present in addition, thereby have increased the security risk of integral device.
Summary of the invention
Technical matters to be solved by this invention is: a kind of photovoltaic combining inverter insulation impedance supervisory circuit is provided, this supervisory circuit can reliable detection go out the situation that positive bus-bar insulation against ground impedance does not meet the demands, negative busbar insulation against ground impedance does not meet the demands, positive and negative busbar does not meet the demands simultaneously, and the product safety performance that increases, also reduced corresponding cost.
For solving the problems of the technologies described above, technical scheme of the present invention is: a kind of photovoltaic combining inverter insulation impedance supervisory circuit, comprise the resistance string that is in series by several resistance, two-way TVS pipe and two isolation optocouplers, the two ends of resistance string are connected to the positive and negative two ends of inverter dc bus; The former avris reverse parallel connection of two isolation optocouplers is also in parallel with two-way TVS; Draw wire in the middle of the resistance string and connect two former avris of isolation optocoupler, wire passes ground connection behind the optocoupler, and positive and negative bus is to the resistance value difference of wire leading point; The collector of two isolation optical coupling secondary edges sides connects respectively the control power supply, and the emitter of two isolation optical coupling secondary edges sides connects respectively the 0V end of control power supply by current-limiting resistance.
As a kind of preferred scheme, described positive bus-bar is different to the resistance value of wire leading point from negative busbar to the resistance value of wire leading point.
After having adopted technique scheme, effect of the present invention is: when insulation impedance does not meet the demands between positive bus-bar and the ground, the emitter of one of them isolation optocoupler will change into high level by low level, and insulation impedance does not meet the demands between positive bus-bar and the ground thereby detect; When insulation impedance does not meet the demands between negative busbar and the ground, the emitter of another isolation optocoupler will change into high level by low level, and insulation impedance does not meet the demands between negative busbar and the ground thereby detect; When positive and negative bus does not meet the demands simultaneously, the emitter that still has an isolation optocoupler will change into high level by low level, not meet the demands thereby detect insulation impedance.And adopt isolation optocoupler and two-way TVS pipe, can guarantee that this testing circuit is accurate, safety.
Description of drawings
The present invention is further described below in conjunction with drawings and Examples.
Fig. 1 is the circuit theory diagrams of the embodiment of the invention;
Fig. 2 is the operational flow diagram of the embodiment of the invention;
In the accompanying drawing: 1. positive bus-bar; 2. negative busbar; 3. two-way TVS manages; 4. isolation optocoupler; 5. resistance string; 6. control power supply; 7. current-limiting resistance; 8.0V end.
Embodiment
The present invention is described in further detail below by specific embodiment.
As shown in Figure 1, a kind of photovoltaic combining inverter insulation impedance supervisory circuit, comprise the resistance string 5 that is formed by several resistance string 5,3 and two isolation of two-way TVS pipe optocoupler 4, be respectively U1 and U2 in the present embodiment, the two ends of resistance string 5 are connected to the positive and negative two ends of inverter dc bus; The former avris reverse parallel connection of two isolation optocouplers 4 is also in parallel with two-way TVS; Draw wires in the middle of the resistance string 5 and connect two isolation optocoupler 4 former avris, wire passes ground connection behind the optocoupler, and positive and negative bus 2 is different to the resistance value of wire leading point; The emitter that the collector of two isolation optocoupler 4 secondary sides connects respectively 6, two isolation of control power supply optocoupler, 4 secondary sides passes through respectively the 0V end 8 that current-limiting resistance 7 connects control power supplys 6.The ratio of described positive bus-bar 1 to the resistance value of wire leading point and negative busbar 2 to the resistance value of wire leading point is 3:1, certainly, they can also be other ratios, but preferred described positive bus-bar 1 be different to the resistance value of wire leading point from negative busbar 2 to the resistance value of wire leading point.
When insulation impedance does not meet the demands between positive bus-bar 1 and the ground, therefore, then form the loop generation current between positive bus-bar 1 and the ground, current direction is that positive bus-bar 1 flows to ground connection, at this moment, the light emitting diode of isolation optocoupler 4U1 is communicated with luminous, like this, the secondary side joint of isolation optocoupler 4U1 is subject to signal, and emitter then changes into high level by original low level; When insulation impedance does not meet the demands when negative busbar 2 and between hanging down, then form the loop generation current between negative busbar 2 and the ground, current direction is that ground wire flows to negative busbar 2, at this moment, the light emitting diode of isolation optocoupler 4U2 is communicated with luminous, like this, the secondary side joint of isolation optocoupler 4U2 is subject to signal, and emitter then changes into high level by original low level.And when insulation impedance did not meet the demands between positive bus-bar 1, negative busbar 2 and ground, same, the emitter of U1 changed into high level by low level.
As shown in Figure 2, when the DC side of inverter was under-voltage, inverter was not worked; When surpass to set threshold values before the dc voltage, when inverter not yet moves generating, inverter can detect positive and negative bus 2 insulation against ground impedances automatically, when the safety requirement is not satisfied in positive and negative bus 2 insulation against ground impedances, system then can report to the police, and can't from, require then can normally start if safety is satisfied in the insulation against ground impedance.
The above only is preferred implementation of the present invention, should be pointed out that for those skilled in the art, under the prerequisite that does not break away from the principle of the invention, can also make some improvement, and these improvement also should be considered as protection scope of the present invention.
Claims (2)
1. photovoltaic combining inverter insulation impedance supervisory circuit is characterized in that: comprise the resistance string that is in series by several resistance, two-way TVS pipe and two isolation optocouplers, the two ends of resistance string are connected to the positive and negative two ends of inverter dc bus; The former avris reverse parallel connection of two isolation optocouplers is also in parallel with two-way TVS; Draw wire in the middle of the resistance string and connect two former avris of isolation optocoupler, wire passes ground connection behind the optocoupler, and positive and negative bus is to the resistance value difference of wire leading point; The collector of two isolation optical coupling secondary edges sides connects respectively the control power supply, and the emitter of two isolation optical coupling secondary edges sides connects respectively the 0V end of control power supply by current-limiting resistance.
2. a kind of photovoltaic combining inverter insulation impedance supervisory circuit as claimed in claim 1 is characterized in that: described positive bus-bar is different to the resistance value of wire leading point from negative busbar to the resistance value of wire leading point.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2012105584490A CN103018572A (en) | 2012-12-20 | 2012-12-20 | Photovoltaic grid-connected inverter insulation resistance monitoring circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2012105584490A CN103018572A (en) | 2012-12-20 | 2012-12-20 | Photovoltaic grid-connected inverter insulation resistance monitoring circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN103018572A true CN103018572A (en) | 2013-04-03 |
Family
ID=47967405
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2012105584490A Pending CN103018572A (en) | 2012-12-20 | 2012-12-20 | Photovoltaic grid-connected inverter insulation resistance monitoring circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN103018572A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109254235A (en) * | 2018-11-26 | 2019-01-22 | 重庆长安汽车股份有限公司 | The insulation monitoring device and method of new-energy automobile exchange harness |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2424080A1 (en) * | 1974-05-17 | 1975-11-27 | Rudolf Dipl Ing Stroemer | Leakage to earth detector - consists of two antiparallel diodes, of which at least one is light emitting diode |
| CN1070486A (en) * | 1992-09-21 | 1993-03-31 | 辽源电业局 | DC grounding monitor alarm device |
| JP4062979B2 (en) * | 2002-06-05 | 2008-03-19 | 株式会社村田製作所 | Insulation resistance measuring device |
| JP4682037B2 (en) * | 2005-12-22 | 2011-05-11 | 矢崎総業株式会社 | Insulation detector |
| CN102279317A (en) * | 2011-06-23 | 2011-12-14 | 广东易事特电源股份有限公司 | Online detection method of insulating resistance to ground of photovoltaic grid-connected inverter |
| CN102298091A (en) * | 2011-05-16 | 2011-12-28 | 江苏斯达工业科技有限公司 | Detection circuit of direct-current power supply insulation resistance to ground |
| CN102621394A (en) * | 2012-03-30 | 2012-08-01 | 广东易事特电源股份有限公司 | System and method for detecting insulation resistance to ground of dual-branch input photovoltaic grid-connected inverter |
| CN202975166U (en) * | 2012-12-20 | 2013-06-05 | 江苏宏宝电子有限公司 | Monitoring circuit for insulation impedance of photovoltaic grid-connected inverter |
-
2012
- 2012-12-20 CN CN2012105584490A patent/CN103018572A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2424080A1 (en) * | 1974-05-17 | 1975-11-27 | Rudolf Dipl Ing Stroemer | Leakage to earth detector - consists of two antiparallel diodes, of which at least one is light emitting diode |
| CN1070486A (en) * | 1992-09-21 | 1993-03-31 | 辽源电业局 | DC grounding monitor alarm device |
| JP4062979B2 (en) * | 2002-06-05 | 2008-03-19 | 株式会社村田製作所 | Insulation resistance measuring device |
| JP4682037B2 (en) * | 2005-12-22 | 2011-05-11 | 矢崎総業株式会社 | Insulation detector |
| CN102298091A (en) * | 2011-05-16 | 2011-12-28 | 江苏斯达工业科技有限公司 | Detection circuit of direct-current power supply insulation resistance to ground |
| CN102279317A (en) * | 2011-06-23 | 2011-12-14 | 广东易事特电源股份有限公司 | Online detection method of insulating resistance to ground of photovoltaic grid-connected inverter |
| CN102621394A (en) * | 2012-03-30 | 2012-08-01 | 广东易事特电源股份有限公司 | System and method for detecting insulation resistance to ground of dual-branch input photovoltaic grid-connected inverter |
| CN202975166U (en) * | 2012-12-20 | 2013-06-05 | 江苏宏宝电子有限公司 | Monitoring circuit for insulation impedance of photovoltaic grid-connected inverter |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109254235A (en) * | 2018-11-26 | 2019-01-22 | 重庆长安汽车股份有限公司 | The insulation monitoring device and method of new-energy automobile exchange harness |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103986192B (en) | A kind of non-isolated photovoltaic grid-connected inverter and grid-connected photovoltaic system | |
| CN101509946A (en) | Phase-lacking and power down detecting method for three phase AC input power supply | |
| CN204168233U (en) | Many groups optical crosstalk volt fault of converter testing circuit | |
| US10128661B2 (en) | Status indicator for power generation systems | |
| CN111983389A (en) | Device for detecting alignment and fault of multi-core cable | |
| CN204029102U (en) | A kind of electrical fire monitoring device based on modified two lines bus | |
| CN102508191B (en) | Device and method for detecting fault of high voltage transformer of electric locomotive | |
| CN102385036B (en) | Method and circuit for detecting alternating-current fuse failure of uninterruptible power supply | |
| CN202975166U (en) | Monitoring circuit for insulation impedance of photovoltaic grid-connected inverter | |
| CN104216452A (en) | Pipe-to-soil potential excessively-negative control method and device for buried pipeline | |
| CN203673002U (en) | Direct current system earth fault searching device | |
| CN204065296U (en) | There is the ring main unit fault-indicating system of anti-misoperation function | |
| CN103018572A (en) | Photovoltaic grid-connected inverter insulation resistance monitoring circuit | |
| CN202586293U (en) | A leakage protection circuit of vehicle-mounted inverter and a corresponding vehicle-mounted inverter | |
| CN106230409A (en) | A kind of IGBT parallel drivers of band NTC acquisition function | |
| CN107240910A (en) | A kind of direct-current micro-grid earth-fault protection method | |
| CN207601191U (en) | A kind of relay protection outlet pulse-detecting circuit | |
| CN203825172U (en) | DC power supply system alternating current mixed detection device | |
| CN101771768A (en) | Digital conference system | |
| CN104090245B (en) | The detection means that a kind of DC power-supply system alternating current is mixed into | |
| CN103888070A (en) | Remote monitor type photovoltaic connecting box based on voltage detection and single-wire communication protocol | |
| CN106026054B (en) | One kind outputing self-checking circuit | |
| CN214013869U (en) | Reliable single-phase wiring detection circuit of commercial power | |
| CN204290313U (en) | A kind of building DC power supply | |
| CN103063972A (en) | Photovoltaic grid-connected inverter direct current reverse-connection prevention detection system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C02 | Deemed withdrawal of patent application after publication (patent law 2001) | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20130403 |