CN108736451A - Overcurrent protection method and device for large power inverter power source - Google Patents
Overcurrent protection method and device for large power inverter power source Download PDFInfo
- Publication number
- CN108736451A CN108736451A CN201710268742.6A CN201710268742A CN108736451A CN 108736451 A CN108736451 A CN 108736451A CN 201710268742 A CN201710268742 A CN 201710268742A CN 108736451 A CN108736451 A CN 108736451A
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- signal
- voltage
- voltage magnitude
- overcurrent
- operating current
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Classifications
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H7/00—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
- H02H7/10—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for converters; for rectifiers
- H02H7/12—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for converters; for rectifiers for static converters or rectifiers
- H02H7/122—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for converters; for rectifiers for static converters or rectifiers for inverters, i.e. dc/ac converters
- H02H7/1227—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for converters; for rectifiers for static converters or rectifiers for inverters, i.e. dc/ac converters responsive to abnormalities in the output circuit, e.g. short circuit
Abstract
The present invention relates to the improvement to overcurrent protection technology.The present invention provides the overcurrent protection methods for large power inverter power source, including：Sample of signal step acquires the operating current of large power inverter power source, obtains the current amplitude signal of operating current and voltage magnitude signal corresponding with the operating current；Voltage magnitude signal is first compared by multilevel iudge step with preset voltage threshold, judges whether voltage magnitude signal is more than voltage threshold；Judge whether the overcurrent time that voltage magnitude signal is more than voltage threshold is more than preset overcurrent time threshold again；And step is as a result exported, if voltage magnitude signal is more than voltage threshold, and the overcurrent time is more than overcurrent time threshold, then triggers alarming step.The present invention also provides overcurrent protections corresponding with the above method.The present invention solves the problems, such as to realize the accurate protection of overcurrent due to the wrong report that signal interference causes momentary pulse excessively high and occurs in overcurrent protection.
Description
Technical field
The present invention relates to circuit design field more particularly to a kind of overcurrent protection technologies.Method provided by the invention and
Device is particularly suitable for high power contravariant welding machine.
Background technology
Overcurrent protection (Over Current Protection) refers to making protection when electric current is more than predetermined maximum
A kind of protected mode of device action.Including especially need in the circuit system of large power inverter power source in circuit design
By overcurrent protection technology be applied to overcurrent, overvoltage, overheat, power on when system safeguard protection, to avoid
The safety accidents such as explosion occur.
Traditional overcurrent protection method and device only judges that pulse height is generally by the way of sampling current amplitude
No is more than to preset protection point to come whether judging overcurrent, it is easy to appear occur momentary pulse mistake due to signal interference in this way
The wrong report phenomenon that height is brought influences the normal continuous operation of system.Also, be required for again after alarm every time it is online, to big
The big operational efficiency for reducing system.
Invention content
The technical purpose of the present invention is to solve the defect of the above-mentioned prior art, solve in overcurrent protection since signal is dry
The wrong report problem for causing momentary pulse excessively high and occurring is disturbed, excess current protective function can accurately and timely be realized by providing one kind
Method and apparatus, realize the accurate protection of overcurrent.Method and apparatus provided by the present invention are particularly suitable for high-power
Inverter system.
The technical purpose of the present invention is realized using following technical scheme.
As one aspect of the present invention, the overcurrent protection side provided by the present invention for large power inverter power source
Method includes the following steps：
Sample of signal step acquires the operating current of large power inverter power source, obtains the current amplitude signal of operating current
The corresponding voltage magnitude signal with operating current；
Voltage magnitude signal is first compared by multilevel iudge step with preset voltage threshold, judges that voltage magnitude is believed
Number whether be more than voltage threshold；Judge whether the overcurrent time that voltage magnitude signal is more than voltage threshold is more than preset overcurrent again
Time threshold；And
As a result step is exported, if voltage magnitude signal is more than voltage threshold, and the overcurrent time is more than overcurrent time threshold,
Then trigger alarming step.
As another aspect of the present invention, the overcurrent protection provided by the present invention for large power inverter power source fills
It sets, comprises the following modules：
Sample of signal module, the operating current for acquiring large power inverter power source obtain the current amplitude of operating current
Signal and voltage magnitude signal corresponding with operating current；
Multilevel iudge module for comparison voltage amplitude signal and preset voltage threshold, and judges voltage magnitude signal
Whether it is more than voltage threshold；For judging whether the overcurrent time that voltage magnitude signal is more than voltage threshold is more than preset overcurrent
Time threshold；And
As a result output module, for when voltage magnitude signal is more than voltage threshold and the overcurrent time is more than the overcurrent time
When threshold value, alarm module is triggered.
Sampling current amplitude carries out the mode of pulse height comparison compared with the prior art, and the present invention is compared using two level
Mode, the first order first compare amplitude, judge whether voltage magnitude signal is more than voltage threshold, and the second level uses window comparator,
Judge that overcurrent time, i.e. voltage magnitude signal are more than whether the overcurrent time of voltage threshold is more than preset overcurrent time threshold,
The overcurrent for only meeting certain time length just thinks to need to alarm, to solve in overcurrent protection since signal interference causes
The wrong report problem that momentary pulse is excessively high and occurs substantially reduces wrong report, the accurate protection of overcurrent is realized, to provide
The stability and operational efficiency of system operation.
Description of the drawings
Fig. 1 gives the implementation schematic diagram of the overcurrent protection method of the present invention；
Fig. 2 gives a kind of implementation schematic diagram of preferred embodiment of the overcurrent protection method of the present invention；
Fig. 3 gives the implementation schematic diagram of another preferred embodiment of the overcurrent protection method of the present invention；
Fig. 4 gives the master-plan schematic diagram of the overcurrent protection of the present invention；
Fig. 5 gives a kind of implementation schematic diagram of preferred embodiment of the overcurrent protection of the present invention；
Fig. 6 gives a kind of embodiment of sample of signal module in overcurrent protection of the invention；And
Fig. 7 gives a kind of embodiment of multilevel iudge module in overcurrent protection of the invention.
Specific implementation mode
Technical scheme of the present invention is described in further details with reference to the accompanying drawings and detailed description.
As one aspect of the present invention, the overcurrent protection side provided by the present invention for large power inverter power source
Method includes the following steps, shown in Fig. 1 and Fig. 4：
Sample of signal step 101 acquires the operating current of large power inverter power source 10, obtains the electric current of above-mentioned operating current
Amplitude signal and voltage magnitude signal corresponding with operating current；
Voltage magnitude signal is first compared with preset voltage threshold, judges electricity by multilevel iudge step 102 and 103
Whether pressure amplitude value signal is more than voltage threshold；Judge whether the overcurrent time that voltage magnitude signal is more than voltage threshold is more than pre- again
If overcurrent time threshold；And
As a result step 104 is exported, if voltage magnitude signal is more than voltage threshold, and the overcurrent time is more than overcurrent time threshold
Value, then trigger alarming step.
Fig. 2 gives the further embodiment of sample of signal step 101, shown in Figure 2, sample of signal step 101
It may particularly include：
Signal acquisition step 1011 acquires the operating current of large power inverter power source 10, obtains the electric current width of operating current
Value signal；And
Current amplitude signal is converted to voltage magnitude signal, obtained opposite with operating current by signal switch process 1012
The voltage magnitude signal answered.
It advanced optimizes on this basis, Fig. 3 gives more preferably embodiment, referring to Fig. 3 and Fig. 5, sample of signal step
Rapid 101 may particularly include：
Signal acquisition step 1011 acquires the operating current of large power inverter power source 10, obtains the electric current width of operating current
Value signal；
Current amplitude signal is filtered by signal filter step 1013, obtains filtered current amplitude signal；With
And
Filtered current amplitude signal is converted to voltage magnitude signal by signal switch process 1012, obtains work electricity
The voltage magnitude signal of stream.
As another aspect of the present invention, the overcurrent protection provided by the present invention for large power inverter power source fills
100 are set, is comprised the following modules, shown in Fig. 1~Fig. 4：
Sample of signal module 201, the operating current for acquiring large power inverter power source 10 obtain the electric current of operating current
Amplitude signal and voltage magnitude signal corresponding with operating current；
Multilevel iudge module 202 for comparison voltage amplitude signal and preset voltage threshold, and judges that voltage magnitude is believed
Number whether be more than voltage threshold；For judging whether the overcurrent time that voltage magnitude signal is more than voltage threshold is more than preset mistake
Flow time threshold；And
As a result output module 203, for when voltage magnitude signal is more than voltage threshold and the overcurrent time is more than overcurrent
Between threshold value when, trigger alarm module 30.
Above-mentioned sample of signal module 201 can further comprise, shown in Figure 2：
Signal acquisition module 2011, the operating current for acquiring large power inverter power source 10 obtain the electricity of operating current
Flow amplitude signal；And
Signal conversion module 2012 obtains and operating current for current amplitude signal to be converted to voltage magnitude signal
Corresponding voltage magnitude signal.
More optimally, Fig. 5 gives the another preferred embodiment of sample of signal module 201, the sample of signal module 201
It specifically includes：
Signal acquisition module 2011, the operating current for acquiring large power inverter power source 10 obtain the electricity of operating current
Flow amplitude signal；
Signal filter module 2013 obtains filtered current amplitude signal for current amplitude signal to be filtered；
And
Signal conversion module 2012 obtains work for filtered current amplitude signal to be converted to voltage magnitude signal
Make the voltage magnitude signal of electric current.
Sampling current amplitude carries out the mode of pulse height comparison compared with the prior art, provided by the present invention excessively electric
Guard method and device are flowed, using two level manner of comparison, the first order first compares amplitude, judges whether voltage magnitude signal is more than electricity
It presses threshold value, the second level to use window comparator, judges the overcurrent time, i.e. voltage magnitude signal is more than the overcurrent time of voltage threshold
Whether it is more than preset overcurrent time threshold, the overcurrent for only meeting certain time length just thinks to need to alarm, to solve
Due to the wrong report problem that signal interference causes momentary pulse excessively high and occurs in overcurrent protection, wrong report is substantially reduced, is realized
The accurate protection of overcurrent, to providing the stability and operational efficiency of system operation.
Fig. 6 gives a kind of embodiment of sample of signal module in overcurrent protection of the invention.Reality shown in Fig. 6
It applies in example, signal acquisition module 2011 is taken as current transformer 2001, and signal conversion module 2012 includes first resistor 501, the
One diode 301, the second diode 302, third diode 303, the 4th diode 304.Wherein, the both ends of first resistor 501
It is connected to signal acquisition module 2011, i.e., the current transformer 2001 in the present embodiment；The cathode and third of first diode 301
The anode of diode 303 links together, and is connected to one end of first resistor 501；The cathode and the 4th of second diode 302
The anode of diode 304 links together, and is connected to the other end of first resistor 501；The cathode of third diode 303 and
The cathode of four diodes 304 links together, and is grounded；And first diode 301 anode and second diode 302
Anode links together, and the voltage magnitude signal of output services electric current.In the embodiment shown in fig. 6, signal filter module
2013 are taken as the first capacitance 401, and the first capacitance 401 is connected in parallel on the both ends of first resistor 501, plays a filtering role.
It can not include the signal filter module 2013 being made of first resistor 501 in above-mentioned sample of signal module 201 yet, it can
It is realized using other embodiment.
Fig. 7 gives a kind of preferred embodiment of multilevel iudge module 202 in overcurrent protection of the invention.The reality
Apply in example, multilevel iudge module 202 includes twin voltage comparator, the first comparator 601 in the twin voltage comparator be used for than
Compared with voltage magnitude signal and preset voltage threshold, and judge whether voltage magnitude signal is more than voltage threshold, twin voltage compares
Whether overcurrent time of second comparator 602 for multilevel iudge voltage magnitude signal to be more than voltage threshold in device is more than default
Overcurrent time threshold.The model of the twin voltage comparator is preferably LM393.In the embodiment, multilevel iudge module 202 is except packet
Also include the components such as multiple resistance, capacitance, diode outside containing first comparator 601 and the second comparator 602, it is specific as follows：
For first comparator 601 for carrying out pulse height comparison, wherein resistance 502 and capacitance 402 forms filter circuit, and two
Pole pipe 305 is zener diode, and the pin 5 of first comparator 601 is that over-current signal input terminal (is used for the electricity of input service electric current
Pressure amplitude value signal), pin 6 is predetermined pulse Height input terminal (for inputting preset voltage threshold).Work as over-current signal
When more than predetermined pulse Height, 7 level of pin of first comparator 601 will pass through 506 He of resistance by low level usually
The charging circuit that capacitance 403 forms slowly rises, and the resistance value of resistance 506 and the capacitance of capacitance 403 determine the charging time.
If first order pulse excessively high signal duration is long, the pin 7 of first comparator 601 will be charged to be compared more than second
The input voltage of the pin 3 of device 602 at this point, the pin 1 of the second comparator 602 will be become low level from high level, and was incited somebody to action
Stream signal OC5V is output to processor module, and to trigger alarm module, wherein resistance 507 is pull-up resistor, and capacitance 404 is filter
Wave capacitance, resistance 508 and capacitance 405 form filter circuit.It is more than limit value that the advantages of doing so, which is exactly in judgement pulse height,
Meanwhile can reduce because signal interference and caused by momentary pulse spike it is excessively high and caused by overcurrent erroneous judgement.
Those skilled in the art will also understand is that, various illustrative logical blocks, list in conjunction with described in disclosure herein
Member, circuit and algorithm steps may be implemented as the combination of electronic hardware, computer software or both.It is hard in order to clearly demonstrate
This interchangeability of part and software, with regard to various exemplary components, square, unit, circuit and step function to its into
General description is gone.This function is implemented as software and is also implemented as hardware depending on concrete application and application
To the design constraint of whole system.Those skilled in the art can in various ways realize described for each concrete application
Function, but this realization decision should not be interpreted as causing a departure from the scope of the present.
The foregoing is only a preferred embodiment of the present invention, is not intended to restrict the invention, for the skill of this field
For art personnel, the invention may be variously modified and varied.All within the spirits and principles of the present invention, any made by repair
Change, equivalent replacement, improvement etc., should all be included in the protection scope of the present invention.
Claims (11)
1. a kind of overcurrent protection method for large power inverter power source, which is characterized in that include the following steps：
Sample of signal step acquires the operating current of the large power inverter power source, obtains the current amplitude of the operating current
Signal and voltage magnitude signal corresponding with the operating current；
The voltage magnitude signal is first compared with preset voltage threshold, judges the voltage amplitude by multilevel iudge step
Whether value signal is more than the voltage threshold；Judge that the voltage magnitude signal is more than the overcurrent time of the voltage threshold to be again
No is more than preset overcurrent time threshold；And
As a result step is exported, if the voltage magnitude signal is more than the voltage threshold, and the overcurrent time is more than described
Overcurrent time threshold, then trigger alarming step.
2. overcurrent protection method described in accordance with the claim 1, it is characterised in that：
The sample of signal step specifically includes：
Signal acquisition step acquires the operating current of the large power inverter power source, obtains the current amplitude of the operating current
Signal；And
The current amplitude signal is converted to voltage magnitude signal, obtained opposite with the operating current by signal switch process
The voltage magnitude signal answered.
3. overcurrent protection method described in accordance with the claim 1, it is characterised in that：
The sample of signal step specifically includes：
Signal acquisition step acquires the operating current of the large power inverter power source, obtains the current amplitude of the operating current
Signal；
The current amplitude signal is filtered by signal filter step, obtains filtered current amplitude signal；And
The filtered current amplitude signal is converted to voltage magnitude signal by signal switch process, obtains the work electricity
The voltage magnitude signal of stream.
4. a kind of overcurrent protection for large power inverter power source, it is characterised in that：
The device comprises the following modules,
Sample of signal module, the operating current for acquiring the large power inverter power source obtain the electric current of the operating current
Amplitude signal and voltage magnitude signal corresponding with the operating current；
Multilevel iudge module for the voltage magnitude signal and preset voltage threshold, and judges the voltage magnitude
Whether signal is more than the voltage threshold；For judging that the voltage magnitude signal is more than the overcurrent time of the voltage threshold to be
No is more than preset overcurrent time threshold；And
As a result output module, for working as, the voltage magnitude signal is more than the voltage threshold and the overcurrent time is more than
When the overcurrent time threshold, alarm module is triggered.
5. overcurrent protection according to claim 4, it is characterised in that：
The sample of signal module specifically includes：
Signal acquisition module, the operating current for acquiring the large power inverter power source obtain the electric current of the operating current
Amplitude signal；And
Signal conversion module obtains and the operating current for the current amplitude signal to be converted to voltage magnitude signal
Corresponding voltage magnitude signal.
6. overcurrent protection according to claim 4, it is characterised in that：
The sample of signal module specifically includes：
Signal acquisition module, the operating current for acquiring the large power inverter power source obtain the electric current of the operating current
Amplitude signal；
Signal filter module obtains filtered current amplitude signal for the current amplitude signal to be filtered；With
And
Signal conversion module obtains the work for the filtered current amplitude signal to be converted to voltage magnitude signal
Make the voltage magnitude signal of electric current.
7. according to overcurrent protection described in claim 5 or 6, it is characterised in that：
The signal acquisition module is HF current transformer.
8. according to overcurrent protection described in claim 5 or 6, it is characterised in that：
The signal conversion module includes first resistor, the first diode, the second diode, third diode, the 4th diode,
Wherein,
The both ends of the first resistor are connected to the signal acquisition module,
The anode of the cathode of first diode and the third diode links together, and is connected to the first resistor
One end；
The anode of the cathode of second diode and the 4th diode links together, and is connected to the first resistor
The other end；
The cathode of the cathode of the third diode and the 4th diode links together, and is grounded；And
The anode of first diode and the anode of second diode link together, and export the operating current
Voltage magnitude signal.
9. overcurrent protection according to claim 8, it is characterised in that：
The signal filter module includes the first capacitance,
First capacitance is connected in parallel on the both ends of the first resistor.
10. overcurrent protection according to claim 4, it is characterised in that：
The multilevel iudge module includes twin voltage comparator,
First comparator in the twin voltage comparator is used for the voltage magnitude signal and preset voltage threshold, and
Judge whether the voltage magnitude signal is more than the voltage threshold, the second comparator in the twin voltage comparator be used for than
Whether it is more than preset overcurrent time threshold compared with the voltage magnitude signal is judged more than the overcurrent time of the voltage threshold.
11. overcurrent protection according to claim 10, it is characterised in that：
The model LM393 of the twin voltage comparator.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710268742.6A CN108736451A (en) | 2017-04-24 | 2017-04-24 | Overcurrent protection method and device for large power inverter power source |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710268742.6A CN108736451A (en) | 2017-04-24 | 2017-04-24 | Overcurrent protection method and device for large power inverter power source |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN108736451A true CN108736451A (en) | 2018-11-02 |
Family
ID=63934105
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710268742.6A Pending CN108736451A (en) | 2017-04-24 | 2017-04-24 | Overcurrent protection method and device for large power inverter power source |
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| CN (1) | CN108736451A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112467747A (en) * | 2020-11-20 | 2021-03-09 | 青岛鼎信通讯股份有限公司 | Current control method of tail end low voltage treatment device |
| CN113270997A (en) * | 2021-06-07 | 2021-08-17 | 浙江精英电器有限公司 | Progressive control method and control circuit for surge steps of inverter |
| CN114167970A (en) * | 2021-12-09 | 2022-03-11 | 深圳市海浦蒙特科技有限公司 | Overcurrent protection method and related assembly |
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| CN204651910U (en) * | 2015-06-15 | 2015-09-16 | 林森 | A kind of short-circuit protection circuit |
| CN105322525A (en) * | 2014-07-30 | 2016-02-10 | 罗伯特·博世有限公司 | Short-circuit protection device |
| CN206041795U (en) * | 2016-08-24 | 2017-03-22 | 南京普爱医疗设备股份有限公司 | A real -time protection device that is used for multichannel full -bridge contravariant module |
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN105322525A (en) * | 2014-07-30 | 2016-02-10 | 罗伯特·博世有限公司 | Short-circuit protection device |
| CN204651910U (en) * | 2015-06-15 | 2015-09-16 | 林森 | A kind of short-circuit protection circuit |
| CN206041795U (en) * | 2016-08-24 | 2017-03-22 | 南京普爱医疗设备股份有限公司 | A real -time protection device that is used for multichannel full -bridge contravariant module |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112467747A (en) * | 2020-11-20 | 2021-03-09 | 青岛鼎信通讯股份有限公司 | Current control method of tail end low voltage treatment device |
| CN113270997A (en) * | 2021-06-07 | 2021-08-17 | 浙江精英电器有限公司 | Progressive control method and control circuit for surge steps of inverter |
| CN114167970A (en) * | 2021-12-09 | 2022-03-11 | 深圳市海浦蒙特科技有限公司 | Overcurrent protection method and related assembly |
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Application publication date: 20181102 |