CN106849020B - A kind of power semiconductor protective device - Google Patents
A kind of power semiconductor protective device Download PDFInfo
- Publication number
- CN106849020B CN106849020B CN201611052309.0A CN201611052309A CN106849020B CN 106849020 B CN106849020 B CN 106849020B CN 201611052309 A CN201611052309 A CN 201611052309A CN 106849020 B CN106849020 B CN 106849020B
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- China
- Prior art keywords
- switch
- electric current
- voltage
- current
- potentiometer
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- 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.)
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Classifications
-
- 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
- H02H7/20—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 electronic equipment
- H02H7/205—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 electronic equipment for controlled semi-conductors which are not included in a specific circuit arrangement
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H1/00—Details of emergency protective circuit arrangements
- H02H1/0007—Details of emergency protective circuit arrangements concerning the detecting means
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H11/00—Emergency protective circuit arrangements for preventing the switching-on in case an undesired electric working condition might result
- H02H11/005—Emergency protective circuit arrangements for preventing the switching-on in case an undesired electric working condition might result in case of too low isolation resistance, too high load, short-circuit; earth fault
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
- H02H3/02—Details
- H02H3/06—Details with automatic reconnection
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
- H02H3/08—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to excess current
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
- H02H3/08—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to excess current
- H02H3/093—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to excess current with timing means
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Emergency Protection Circuit Devices (AREA)
- Measurement Of Current Or Voltage (AREA)
Abstract
Description of the invention is a kind of power semiconductor protective device (1), has galvanometer (UR), potentiometer (USW) and switch (SW), wherein the galvanometer (UR) measuring the electric current (I) for passing through the equipment (1), wherein the switch (SW) is suitable for disconnecting through-flow by the electric current of the equipment (1), wherein the potentiometer (USW) voltage switched on (SW) in the on-state is measured, if the galvanometer (UR) measure more than first electric current-threshold (Iref) electric current (I), the switch (SW) just by this way control a predetermined time segment (taus), it is disconnected so that electric current is through-flow, wherein in the scheduled time (taus) interior by the potentiometer (USW) voltage on the opened switch (SW) of measurement, wherein when reclosing, by the voltage (U turned on the switch on (SW)SW) identify short circuit occur, and the switch (SW) is constantly controlled in this way, be disconnected so that electric current is through-flow.
Description
Technical field
The present invention relates to a kind of power semiconductor protective devices.
Background technique
It is known from the state of the art a variety of equipment for protecting power semiconductor.
Wherein, real short circuit and false short circuit are distinguished, being proven is hang-up.False short circuit is, for example,
As especially showed when connecting capacitive load just as short circuit and generate.That is, sometimes sizable
Electric current can flow through, until capacitive load is correspondingly electrically charged.
Therefore, test was constantly repeated in the past, it is false short-circuit to identify.
Such as a kind of electronic insurance equipment as known to 10 2,012 103 551 A1 of patent No. DE, the locking device meeting
Controllable switch is disconnected according to overload current and is reopened according to the voltage change on output end.
The deficiency of these equipment is to be first based on carrying electric current and disconnecting, and only after a certain time could
Enough bases restart condition realization connection.Thus it is frequently necessary to the time of unnecessary length, to charge to capacitive load.In addition, knowing
It is not considerably complicated, since it is desired that saving " history " value.In addition, in this arrangement, it is often very difficult to be, it is opened in switch
Afterwards, capacitive load will be discharged by ohmic load placed side by side, and therefore, identifying system may the capacitor (portion that will be charged
Point) it is identified as short circuit to load errors.The place claim device especially be related to open capacitive load when
Be certified as it is extremely difficult because here early in open when just met disconnection condition and thus without any history
Voltage value is compared.
In addition, any judgement relevant to the virtual condition of switch cannot be made by heretofore known solution, because
Load aspect is only observed herein.
Summary of the invention
Basic goal of the invention is to provide a kind of power semiconductor protective device, is subject to improved and cost advantages
Device is set for detect short circuit, which obviate one or more defects in the prior art.
The solution of above-mentioned purpose passes through feature described in independent claims according to the present invention and obtains.Of the invention has
Benefit design is illustrated by dependent claims.
Wherein:
A kind of power semiconductor protective device includes: galvanometer, potentiometer and switch；The amperometric measurement is logical
The electric current of described device is crossed, the switch measures open shape for disconnecting the current path by described device, the potentiometer
The voltage of the switch under state；Described device includes
If the electric current that the amperometric measurement arrives is more than first current threshold, it is predetermined at one to control the switch
Time internal cutting off current path, within the predetermined time, the voltage of the potentiometer measurement switch；
In the case where reclosing current path, the switch repeats above-mentioned control, by measuring repeatedly cutting electric current
Voltage change decision circuitry when access on switch is with the presence or absence of short circuit.
Be further: the voltage that the potentiometer measures within the time of cutting current path is greater than first voltage threshold value
When, judge load for capacity load.
It is further: the determination of predetermined time current value measured before depending on.
A kind of overload current detection device, including shunt resistance device, the galvanometer in parallel with shunt resistance；Computing unit with
And switch；The galvanometer determines that the electric current by described device, the switch are used by measurement parallel shunt resistance (R) voltage
In the current path that disconnection passes through the equipment；Described device includes
If the electric current of the amperometric measurement is more than the first current threshold, the switch is controlled when one scheduled
Between internal cutting off current path；
The current value of test constantly described device obtains the electric flux of shunt resistance, when electric flux is more than maximum power,
Control the switch permanent shut-down current path.
The present invention is a kind of improved and cost-effective power semiconductor for avoiding one or more disadvantages in the prior art
Protective device.
Detailed description of the invention
By preferred embodiment, the present invention is further explained with reference to the accompanying drawings.
Wherein:
Fig. 1 is the general view according to embodiments of the present invention；
Fig. 2 is the flow chart of embodiments of the present invention.
Specific embodiment
The present invention is illustrated referring to attached drawing deeper into ground below.Here, it is noted that illustrated different aspect can be distinguished
Individually or in combination with one another it is applied.That is, each aspect is come in combination with different embodiments of the invention
It uses, as long as no clearly stating as pure alternative.
In addition, below for simplicity, usually only by an entity.But as long as not being attached with clearly, the present invention can also
It is respectively provided with more related entities.For this respect, using words and phrases, "one" is only understood to refer to, a kind of simple
Embodiment in use at least one entity.
There is galvanometer U in present invention power semiconductor protective device 1 a kind of as shown in Figure 1:R, potentiometer USWAnd switch
SW.For preferably general view, described device 1 is irised out in figure by the frame of dotted line.
The power semiconductor is not required to be shown in the accompanying drawings.That is, the power semiconductor can be with
A kind of element (unshowned), but the switch SW inherently by power semiconductor, such as MOS-FET- transistor
(Metal Oxide Semiconductor Field Effect Transistor) provides.But the present invention is not limited only to this.
Wherein, the galvanometer URThe electric current I that measurement passes through the equipment 1.For this purpose, various forms of electric currents are surveyed in principle
It measures feasible or is magnetic field (such as Rogowski coil, Hall sensor) by being induced, but or be to pass through shunt resistance
Current measurement on R and the like.
The switch SW is used to disconnect the current path by the equipment 1.Various types of switches can be used in principle,
Such as mechanical switch or electronic switch, for example controllable (field-effect) transistor.
In addition, described device uses the potentiometer U measured to the voltage on the switch SWSW.Because of the switch
SW constitutes short circuit in the ideal case, therefore, voltage is measured under the opening state of the switch SW just enough, because
When switch SW is closed, voltage only needs to be zero.
But it can be provided respectively according to the type of the switch SW, such as the switch SW itself constitutes minimum resistance,
Therefore, current measurement, which for example will enable, uses the switch of closing as shunt resistance R.Such a case for example can use half
Occur when conductor switch (such as controllable (field-effect) transistor).
On this point, distribution recited above will be understood to be functional, be not limiting upon actual implementation.
Described device includes
If the galvanometer URThe electric current I of measurement is more than the first current threshold Iref, that is to say, that I > Iref, control in this way
The switch SW is made in one section of predetermined time tausThe current path of inscribe disconnection described device 1.It and then wherein, usually will not be
The current measurement of current path is executed, but only in one section of scheduled minimum on-time t of settingeinIt inside can just measure logical
Cross the electric current I of described device.
It now can be in one section of predetermined time t of cuttingausIt is interior, pass through the potentiometer USWWhat measurement was opened opens
Close the voltage on SW.
This voltage can be saved.Wherein, broad sense will be understood to be by saving, and both may imply that current electricity
Pressure is stored in capacitor, also means the preservation of measured value.
Passing through predetermined time tausLater, the switch SW is turned back on, so that electric current is again through described device 1
It is flowed towards supported V.
If now since overload current manipulates the switch SW repeatedly, by repeatedly would measuring voltage USWVariation
Come whether decision circuitry occurs constituting the real short circuit of grave danger.
Thus it achieves that, it may be assumed that in the case where (repeatedly) cuts off and capacity load V occurs, potentiometer USWInstitute
It states the voltage measured on switch SW and is less than voltage rating.This is because, capacity load is charged by the electric current flowed through, because
This this be there is the voltage to charge by electric current on the capacity load V after switch SW opening.In contrast to this
It is that in actual circuit, after switch SW opening, therefore the voltage in terms of the load is 0 volt.
This for example can press measurement to prove by simple difference, such as wheatstone measurement bridge or calculus of differences amplification
Various other suitable devices on device or switch SW are confirmed.
There are real short circuit, the permanent turn-off current access of the switch SW is controlled.
Wherein, control can be the control (" opening ") of active or passively stop (" closing "), open depending on described
Close the type of SW.That is, the switch SW can both be implemented as opener, closer can also be implemented as.
In addition, being identified in the advantageous design of another kind of the invention, since the charging of capacity load occurs in short-term
Overload current.If potentiometer USWIn current path short interruptions tausThe voltage on the switch SW is measured during process
More than first voltage threshold value Uref, so that it may think that load is capacity load V.Simple illustration is, it may be assumed that (repeatedly) cutting with
And in the case where there is capacity load V, it will appear the voltage U less than voltage rating on the switch SWSW.This is because, electric
Holding load is to be charged by the electric current flowed through, therefore exist on the capacitive load V after switch SW opening and pass through
The voltage of electric current charging.This voltage U in the loadVLead to switch USWOn voltage be less than voltage rating.With regard to this respect
For, can now be existed by difference and (be equal to Uref=0V) or by particular differences presence (be equal to Udiff=UNetz-UV> Uref) identification
Capacity load V out.But switch U on this point, can also be passed throughSWOn voltage identify capacitor based on specific limit value is less than
Property load presence.
In addition, in still another advantageous design of the invention, the predetermined time t of disconnectionausDetermination depend on before
Measured electric current I.That is, electric current I is for example significantly greater than current threshold Iref, then, when electric current just can be cut off longer
Between, and current threshold I is only slightly greater than in such as electric currentrefIn the case where, then, electric current just can be severed the shorter time.Cause
This, such as semiconductor switch is not to be overloaded, and the only quick charge of capacitive load.
Certainly the design of the invention that can also such as get off.
A kind of overload current detection device 1, including the galvanometer U with shunt resistance RR, computing unit SE and switch SW.
The galvanometer URBy the electric current of the voltage measurement described device 1 on the shunt resistance R, the switch SW is used
In the current path for disconnecting described device 1.As described above, the shunt resistance is the internal resistance of the switch SW.
If the galvanometer URThe electric current I measured is more than the first current threshold Iref, then the switch SW is controlled one
Section predetermined time tausInternal cutting off current path.
Current value (the predetermined time t of test constantly described device 1ausIt is interior), obtain the electric flux of known shunt resistance R.Institute
State electric flux can be calculated by electric current and voltage relationship obtain, also by resistance and current relationship, resistance and voltage are measured in other words
It obtains.When electric flux is more than maximum power WmaxIn the case where, control the switch SW permanent shut-down current path.Because working as institute
Internal resistance that shunt resistance is the switch SW (switch SW is electronic switch) is stated, so test constantly described device 1 here
Current value is the test constantly under two states, and one is in predetermined time tausThe interior switch SW opens the state of open circuit
Under, the open circuit internal resistance electric current of electronic switch is measured, it is another to terminate predetermined time tausThe switch SW turn-on current access
Under state, electronic switch short circuit internal resistance electric current is measured.Two kinds of situation maximum power WmaxSetting value it is also different.Certainly there are also one
Kind is when shunt resistance R is the resistance of independent access concatenation switch SW, in end predetermined time tausAfterwards or foregoing description switch SW
In the state of turn-on current access, the electric current of the resistance of independent access concatenation switch SW is measured.
Implement a kind of corresponding process as shown in Figure 2.
In first step S50, the switch SW is controlled in this way, so that current direction supported V.By scheduled
Time teinLater, in the step s 100, measurement passes through the electric current I of described device 1.
In addition, also optionally providing, after step S50, the electricity in terms of supported V is measured also by suitable potentiometer
Press UV.The step for can be carried out during or after in the process of step S100.
It is examined in step S300, if meet disconnection condition, i.e., whether measured electric current I is more than the first current threshold
Iref。
If it is not the case, the system is returned to step S100 and re-executes loop.
If electric current I is greater than the first current threshold Iref, then, the switch SW is just first temporarily beaten in step S400
It opens.
Then, the electric energy W of the switch SW in other words of described device 1 is flowed through in measurement.Here, being according to this measurement respectively
It is no also to measure voltage, to measure the voltage U on the switch SWSW, but by known resistance R and previously measured
Electric current measures electric energy W.
If electric energy W is greater than specific maximum power Wmax, then, the switch SW is just not switched on and above-mentioned stream
Journey terminates.
If electric energy W is on the contrary to be less than (or being equal to) specific maximum power W hereinmax, then in step S675, just etc.
To a period of time taus, above-mentioned process brings into operation from step S50 again.
Certainly, the condition for being more than can also be equally replaced by other conditions.
The step mentioned above component part that device can be control unit SE in other words is implemented by it in other words.
Control unit can be for example a kind of micro controller or ASIC or FPGA.
The present invention for example can very advantageously be applied to power supply.It often can be appreciated that powerful Switching Power Supply part wherein,
With controllable power semiconductor as switch element.
It, can be on the power semiconductor by the embodiment as switch SW herein it is particularly advantageous that by the present invention
Voltage drop, based on the energy input into the power semiconductor, to measure actual load.The measurement of this energy input
Considerably beyond binary state recognition (capacity load, short circuit), because this identification must be provided largely
Safety margin.
Therefore, it using the above-mentioned present invention, can also realize in case of need in specific period, such as 10,
... electric current is provided in 50ms, the electric current significantly more than specified rated current, such as 2 times to 10 times.
Claims (3)
1. a kind of power semiconductor protective device (1), includes: galvanometer (UR), potentiometer (USW) and switch (SW)；It is described
Galvanometer (UR) by the electric current (I) of described device (1), the switch (SW), which is used to disconnect, passes through described device (1) for measurement
Current path, the potentiometer (USW) measure the voltage for switching (SW) under opening state；It is characterized in that, described device has
Have:
If galvanometer (the UR) electric current (I) that measures is more than the first current threshold (Iref), then control the switch (SW)
In a predetermined time (taus) internal cutting off current path, in the predetermined time (taus) in, the potentiometer (USW) measure and open
Close the voltage of (SW)；
In the case where reclosing current path, the switch (SW) repeats above-mentioned control, by measuring repeatedly cutting electric current
Voltage (the U on (SW) is switched when accessSW) change decision circuitry with the presence or absence of short circuit.
2. protective device according to claim 1, which is characterized in that the potentiometer (USW) in the time of cutting current path
(taus) in the voltage that measures be greater than first voltage threshold value (Uref) when, judge load for capacity load (V).
3. protective device according to claim 1 or claim 2, which is characterized in that the predetermined time (taus) determination depend on it
Preceding measured electric current (I) value.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE102015223359.6A DE102015223359A1 (en) | 2015-11-25 | 2015-11-25 | Device for protecting a power semiconductor |
| DEDE102015223359.6 | 2015-11-25 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN106849020A CN106849020A (en) | 2017-06-13 |
| CN106849020B true CN106849020B (en) | 2019-10-25 |
Family
ID=58692847
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201611052309.0A Active CN106849020B (en) | 2015-11-25 | 2016-11-25 | A kind of power semiconductor protective device |
Country Status (2)
| Country | Link |
|---|---|
| CN (1) | CN106849020B (en) |
| DE (1) | DE102015223359A1 (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2072736U (en) * | 1990-06-07 | 1991-03-06 | 林庆炳 | High-accuracy current time type safety refrigerator circuit |
| CN101320913A (en) * | 2007-06-05 | 2008-12-10 | 佳能株式会社 | Power supply apparatus, power supply apparatus control method |
| CN203787935U (en) * | 2014-04-09 | 2014-08-20 | 太原科技大学 | Over-current protection circuit based on high side current detection |
| CN104659732A (en) * | 2013-11-18 | 2015-05-27 | 上海协同科技股份有限公司 | Overvoltage and overcurrent protecting circuit |
| CN104842801A (en) * | 2014-02-18 | 2015-08-19 | 现代自动车株式会社 | Device and method for interrupting battery current |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE10117892A1 (en) * | 2001-04-10 | 2002-10-17 | Siemens Ag | Limiting circuit against overload of power supply, has timer for controlling current and/or voltage limiting element whose switching time is variable depending on output voltage |
| US7342762B2 (en) * | 2005-11-10 | 2008-03-11 | Littelfuse, Inc. | Resettable circuit protection apparatus |
| DE102007006564A1 (en) * | 2007-02-09 | 2008-08-14 | Siemens Ag | Line safety switch or circuit-breaker comprise input terminal and output terminal, which are connected by current path, where device measures phase of alternating current |
| WO2012064386A1 (en) * | 2010-11-10 | 2012-05-18 | Abb Research Ltd. | Fault interrupting devices and control methods therefor |
| DE102012103551B4 (en) | 2012-04-23 | 2016-06-09 | Block Transformatoren-Elektronik Gmbh | Electronic security device and electronic security system |
-
2015
- 2015-11-25 DE DE102015223359.6A patent/DE102015223359A1/en active Pending
-
2016
- 2016-11-25 CN CN201611052309.0A patent/CN106849020B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2072736U (en) * | 1990-06-07 | 1991-03-06 | 林庆炳 | High-accuracy current time type safety refrigerator circuit |
| CN101320913A (en) * | 2007-06-05 | 2008-12-10 | 佳能株式会社 | Power supply apparatus, power supply apparatus control method |
| CN104659732A (en) * | 2013-11-18 | 2015-05-27 | 上海协同科技股份有限公司 | Overvoltage and overcurrent protecting circuit |
| CN104842801A (en) * | 2014-02-18 | 2015-08-19 | 现代自动车株式会社 | Device and method for interrupting battery current |
| CN203787935U (en) * | 2014-04-09 | 2014-08-20 | 太原科技大学 | Over-current protection circuit based on high side current detection |
Also Published As
| Publication number | Publication date |
|---|---|
| CN106849020A (en) | 2017-06-13 |
| DE102015223359A1 (en) | 2017-06-01 |
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