CN103675416A - Undervoltage-overvoltage protection device and method - Google Patents
Undervoltage-overvoltage protection device and method Download PDFInfo
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- CN103675416A CN103675416A CN201210321607.0A CN201210321607A CN103675416A CN 103675416 A CN103675416 A CN 103675416A CN 201210321607 A CN201210321607 A CN 201210321607A CN 103675416 A CN103675416 A CN 103675416A
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Abstract
The invention discloses an undervoltage-overvoltage protection device which, for each of three alternating-current phases, comprises a sampling circuit used for obtaining a line sampling voltage of the alternating phase, an undervoltage detection circuit and three overvoltage detection circuits, wherein at least one of the overvoltage detection circuits comprises a voltage detection chip.
Description
Technical field
The present invention relates to distribution system for electrical domain, relate in particular to a kind of under-voltage-over-pressure safety device and method.
Background technology
Generally speaking, the voltage in supply line is a steady state value not, and it may the corresponding generation fluctuation because of the variation of load.This voltage fluctuation in supply line (as under-voltage or overvoltage), once exceed the scope that consumer can bear, will bring adverse influence to consumer, even cause the damage of consumer.Therefore, conventionally adopt under-voltage protection and over-pressure safety device to guarantee that consumer moves under normal power supply state.
Under-voltage protection generally refers to when supply line's voltage is for example, during lower than a predetermined threshold (lower than nominal voltage 80%); protective device cuts off supply line automatically; until when line voltage distribution returns to normal range, protective device can manually be returned to on-state again.On the contrary; overvoltage protection for example refers to, when line voltage distribution surpasses a predetermined value (higher than nominal voltage 10%); in order to prevent that consumer is caused to damage, the same line disconnection automatically of protective device and can manually connect again circuit when line voltage distribution recovers normal.
In the market under-voltage-over-pressure safety device mainly adopts 2 discrete tripping coils to realize respectively detection and the protection action of under-voltage and overvoltage.Fig. 1 exemplarily show a kind of existing under-voltage-schematic diagram of over-pressure safety device 100.As shown in Figure 1, the L(of supply line live wire) and N(zero line) be used for providing electric energy to consumer 150.Protective device 100 is arranged on consumer side, and comprises two tripping coils 110 and 120.Tripping coil 110 is for carrying out the action of threading off when under-voltage detecting.Control circuit 140, when overvoltage being detected, triggers tripping coil 120 and carries out the action of threading off, and then drives isolating switch 130 to disconnect supply line to the electrical connection of consumer 150 with mechanical drive mode.
Adopt structure as shown in Figure 1 can realize duplicate protection under-voltage, overvoltage.Yet, as seen from Figure 1, this under-voltage-over-pressure safety device need two independently tripping coil realize respectively under-voltage, overvoltage protection.And each tripping coil is because its volume of feature of its physical construction is relatively large, cost is also higher, particularly compare all the more so with electronic component.This shortcoming obviously can not meet current protective device miniaturization, requirement cheaply.Therefore, proposed at present a kind ofly only with a tripping coil, to realize scheme under-voltage, overvoltage protection.In prior art, the overvoltage of having used 4 comparers to realize three-phase detects, and realizes under-voltage detection and the judgement of three-phase with other 4 comparers.And comparer detects overvoltage or under-voltagely all controls unique tripping coil action after time delay.
Summary of the invention
The present invention be intended to propose a kind of for three-phase power supply system under-voltage-over-pressure safety device and method.This under-voltage-over-pressure safety device can enough less elements realize that overvoltage/undervoltage detects and judgement.And, preferably, can also realize by the relatively low chip of use cost.
According to one aspect of the invention, the present invention propose a kind of under-voltage-overvoltage pick-up unit, for each in three interchanges mutually, this device comprises: a sample circuit, for obtaining the circuit sampled voltage of this interchange phase; One undervoltage detection circuit, for the circuit sampled voltage described interchange phase being detected lower than a under-voltage threshold value after, one schedule time of time delay is exported a under-voltage detection level again; One over-voltage detection circuit for the circuit sampled voltage described interchange phase being detected higher than an overvoltage threshold after, one schedule time of time delay exports an overvoltage again and detects level, one of at least comprises voltage checking chip in wherein said three over-voltage detection circuits; This device also comprises: first gets or circuit, the output of the over-voltage detection circuit of voltage checking chip is asked to not comprising in the output of described three undervoltage detection circuits and described three over-voltage detection circuits or; The first decision circuitry, gets or when circuit is output as described under-voltage detection level or described overvoltage and detects level output dropout trigger pip when described first; Second gets or circuit, to the output of described the first decision circuitry and described in comprise the over-voltage detection circuit of voltage checking chip output ask or; Dropout trigger circuit, get or circuit is output as described dropout trigger pip or described overvoltage and detects level when described second, trigger tripping coil and carry out the action of threading off.
Preferably, described first get or circuit is got the output of the output of described three undervoltage detection circuits and a described over-voltage detection circuit or.More preferably, the voltage checking chip comprising in described over-voltage detection circuit is the voltage checking chip with time delay.Preferably, described the first decision circuitry is also the voltage checking chip with time delay.More preferably, described undervoltage detection circuit comprises comparator circuit and delay circuit, and this delay circuit delay time is longer than the delay time of the voltage checking chip comprising in described over-voltage detection circuit.
The invention allows for a kind of under-voltage-over-pressure safety device, it comprises: be connected to the isolating switch in supply line; The tripping coil that can drive described isolating switch to disconnect; Above-mentioned under-voltage-overvoltage pick-up unit, it is connected to described tripping coil, for occurring overvoltage or when under-voltage, trigger described tripping coil and carry out de-mouthful, to drive described isolating switch to disconnect supply line on one of three-phase power line being detected.
Thus, used voltage checking chip to carry out overvoltage judgement and under-voltage output judgement in the present invention, than traditional comparer, it can be cost-saving, dwindles circuit volume.And, because the voltage checking chip of using in the present invention is with delay function, thereby can further simplify circuit, to realize miniaturization, requirement cheaply.
Accompanying drawing explanation
The following drawings is only intended to the present invention to schematically illustrate and explain, not delimit the scope of the invention.Wherein,
Fig. 1 illustrate existing under-voltage-schematic diagram of over-pressure safety device;
The structural representation of Fig. 2 A-2C exemplarily illustrates under-voltage according to an embodiment of the invention-overvoltage pick-up unit;
Fig. 3 illustrates the output waveform of voltage checking chip.
Embodiment
For technical characterictic of the present invention, object and effect being had more clearly, understand, now contrast accompanying drawing explanation the specific embodiment of the present invention.
Fig. 2 A-2C, (being designated hereinafter simply as Fig. 2) exemplarily shows the schematic diagram of under-voltage according to an embodiment of the invention-overvoltage pick-up unit.Under-voltage according to an embodiment of the invention-overvoltage pick-up unit is arbitrary in the line voltage distribution of three-phase being detected generally be there is mutually overvoltage or triggers the mechanism of dropout when under-voltage, and then impels the isolating switch 130 on circuit to cut off in time for being electrically connected to.
Particularly, as shown in Figure 2, tripping coil 110 can be connected in three interchanges mutually arbitrary upper, and as shown in Figure 2, it is connected on live wire L1 example.Alternating current on L1 is connected to controlled on-off element 270 after rectification circuit D rectification.Tripping coil 110 and on-off element 270 form a series arm.When pick-up unit detects and judges arbitrary interchange and occurs mutually under-voltage or overvoltage, 270 conductings of gauge tap element, short circuit falls to make as the pick-up unit of load tripping coil 110 to have large electric current to flow through to carry out the action of threading off because of moment thus, and then impels relevant isolating switch to disconnect supply line to connect.
In Fig. 2, pick-up unit comprise rectification circuit D, sample circuit 210, undervoltage detection circuit 220, over-voltage detection circuit 230, two get or (OR) unit 240,260 and judging unit 250 and on-off element 270.In Fig. 2, for each the footnote for circuit " AAAx, x=1,2 or 3 " in three interchanges mutually, represent respectively.In the situation that not distinguishing concrete interchange phase, every kind of circuit does not represent with the mark with footnote generally, for example " 240 ".
As shown in Figure 2, for each, exchange phase, be provided with a sample circuit 210x(x=1,2 or 3).210 pairs of single-phase line voltage distributions of each sample circuit are sampled, and obtain single-phase circuit sampled voltage V
lineX(x=1,2 or 3).Sample circuit 210 can be for example the typical series connection bleeder circuit in Fig. 2, the voltage V of sampled point
lineXalso through filtering, process (capacitor C 1x).The stabilivolt arranging in sample circuit 210, plays the effect of pressure limiting, for the maximal value of limited samples point voltage.
As shown in Figure 2, the single-phase circuit sampled voltage V that sample circuit 210 obtains
lineXsend into respectively corresponding undervoltage detection circuit 220x and over-voltage detection circuit 230x, x=1 wherein, 2 or 3.In Fig. 2, each undervoltage detection circuit 220 comprises a comparer 221 and a delay circuit 225.Comparer 221 is by circuit sampled voltage V
lineXwith a reference voltage V
lcompare.If V
lineXbe less than V
l, represent to have occurred under-voltage, comparer 221 output effective values; Otherwise do not have under-voltage, comparer 221 output invalid values.In the example shown in Fig. 2, the in-phase input end of comparer 221 is connected to V
lineX, negative input is connected to reference voltage V
l.Thus, work as V
lineXbe less than V
ltime, the effective low level of comparer 221 output, otherwise the invalid high level of comparer 221 output.Delay circuit 225 is sent in the output of comparer 221.
The effect of delay circuit 225 is that contrast postpones a schedule time compared with the effective value of device 221 output, and 100ms for example, to avoid noise in voltage signal, burr to cause erroneous judgement.In example shown in Fig. 2, delay circuit 225 comprises a triode Q1x who serves as on-off element, it connects into common emitter circuit, and base stage is connected to the output of comparer 221 as controlled end, and its collector is as output terminal and be parallel with the capacitor C 2x of time-lag action.Concrete, when delay circuit 225 work, when comparer is exported invalid high level, Q1x conducting, drags down capacitor C 2x both end voltage, and the current collection of Q1x is low level very.When comparer is exported effective low level, Q1x disconnects, and direct supply Vcc charges to capacitor C 2x, thereby raises the voltage of the collector of Q1x, forms the under-voltage detection signal of high level.Three outputs of undervoltage detection circuit 220 are sent into first and are got or unit 240.
As shown in Figure 2, pick-up unit also comprises three over-voltage detection circuit 230x that exchange phases for three, x=1 wherein, 2 or 3.In the present invention, these three over-voltage detection circuit 230x can, according to adopting the combination of comparer and delay circuit to realize with the similar mode of undervoltage detection circuit, also can realize by voltage checking chip.In the example of Fig. 2, the over-voltage detection circuit 230 of the interchange phase corresponding with live wire L1
1adopt comparator circuit and delay circuit to realize, other two interchanges all adopt voltage checking chip to realize mutually.
Similar with undervoltage detection circuit, over-voltage detection circuit 230
1comprise comparator circuit 231
1with delay circuit 235
1.Wherein, delay circuit 235
1structure identical with the delay circuit 225 in undervoltage detection circuit, repeat no more here.Comparator circuit 231 is by V
line1with a reference voltage V
hcompare.In the example shown in Fig. 2, the end in the same way of comparator circuit 231 is connected with reference voltage V
h, negative end is connected to V
line1.If V
line1>V
h, show to occur that overvoltage, comparator circuit export effective low level, otherwise voltage being normal, comparator circuit is exported invalid high level.Similar with undervoltage detection circuit, the output of comparator circuit 231 is sent into first and is got or unit 240 after delay circuit 235 time delays.
As shown in Figure 2, first get or 240 pairs of unit from three output of undervoltage detection circuit 220 with from over-voltage detection circuit 230
1output get or, that is, if arbitrary in three outputs, be effective high level, export high level, represent that under-voltage or overvoltage has appearred in relevant interchange mutually.In the example shown in Fig. 2, preferably, circuit 220 and circuit 230
1each output terminal all connect a diode D10 ~ D13, the negative electrode of four diodes is connected to the input end of judging unit 250 together, realizes line or (Line-OR).
In Fig. 2, two other exchanges the over-voltage detection circuit 230 of phase
2with 230
3all adopt the voltage checking chip with time delay to realize.Here, voltage checking chip has the voltage Vd of detection and release voltage Vr, as shown in Figure 3.When being input to respectively voltage checking chip 230
2with 230
3the V of VDD pin
line2and V
line3surpass release voltage Vr, and for example, predetermined delay time (200ms) in during not lower than its detection voltage Vd, voltage checking chip 230
2or 230
3export effective high level, represent to have occurred that it is the dropout trigger pip under overpressure situation that overvoltage, this effective high level also can be regarded as.
Return judging unit 250, the judging unit 250 in Fig. 2 adopts a voltage checking chip with delay feature to realize equally.That is to say circuit 220
1, 220
2, 220
3with 230
1output warp or (Line-OR) after send into the VDD input end of voltage checking chip 250.If circuit 220
1, 220
2, 220
3with 230
1have arbitrary effective high level that is output as, that is, occur under-voltage indication or overvoltage indication, this voltage checking chip is input as high level.For example, if this input is higher than the release voltage of this voltage checking chip and be not less than its detection voltage, a judging unit output effective high level, i.e. an effective dropout trigger pip in predetermined delay time (100ms).
The output of judging unit 250 and two over-voltage detection circuits 230
2with 230
3output all send into second and get or unit 260.If circuit 250,230
2with 230
3output in arbitrary be effective dropout trigger pip, this second is got or effective dropout trigger pip is also exported in unit 260 output.Second get or the dropout trigger pip of unit 260 output for driving switch element 270, i.e. controlled silicon conducting in Fig. 2, thus impel tripping coil to carry out the action of threading off, and then by isolating switch 130, disconnect supply lines and connect.
In the example that Fig. 2 provides, delay circuit and each comparer, comparator circuit and the required direct supply of voltage checking chip all obtain from circuit L1.Optionally, this direct supply also can, from All other routes, as L2 and the upper acquisition of L3, or adopt powered battery.The DC power supply circuit providing in Fig. 2 can provide two different direct supply voltages.DC power supply circuit comprises stabilivolt, to obtain constant voltage.
In Fig. 2, second gets or dropout trigger pip that unit 260 sends is coupled to the controllable silicon 270 as on-off element.Controllable silicon 270 conducting under the triggering of dropout trigger pip.Controllable silicon 270 conductings cause rectification circuit D1 all loads afterwards by short circuit, a large electric current of moment tripping coil 110 acquisitions, and carry out therefrom the action of threading off.In the example shown in Fig. 2, in order to maintain the stable of dropout trigger pip, at the output terminal of over-voltage detection circuit, be also connected with the delay circuit of RC parallel connection.Controllable silicon 270 in Fig. 2 can also replace with other controlled switch elements, such as thyristor, relay etc.
Except the situation shown in Fig. 2, two over-voltage detection circuits that exchange phase also can comprise comparer and delay circuit.The principle of work of this over-voltage detection circuit and the circuit in Fig. 2 230
1identical, repeat no more here.Over-voltage detection circuit 330x shown in Fig. 2 can also all realize by overvoltage detection chip, the circuit 230 in its principle of work and Fig. 2
2with 230
3principle identical, also repeat no more here.
Be to be understood that, although this instructions is described according to each embodiment, but not each embodiment only comprises an independently technical scheme, this narrating mode of instructions is only for clarity sake, those skilled in the art should make instructions as a whole, technical scheme in each embodiment also can, through appropriately combined, form other embodiments that it will be appreciated by those skilled in the art that.
The foregoing is only the schematic embodiment of the present invention, not in order to limit scope of the present invention.Any those skilled in the art, not departing from equivalent variations, modification and the combination of doing under the prerequisite of design of the present invention and principle, all should belong to the scope of protection of the invention.
Claims (7)
1. under-voltage-overvoltage pick-up unit (200), is characterized in that:
For each in three interchanges mutually, this device comprises:
One sample circuit (210
1, 210
2, 210
3), for obtaining the circuit sampled voltage of this interchange phase;
One undervoltage detection circuit (220
1, 220
2, 220
3), for the circuit sampled voltage described interchange phase being detected lower than a under-voltage threshold value (V
l) afterwards, one schedule time of time delay is exported a under-voltage detection level again;
One over-voltage detection circuit (230
1, 230
2, 230
3), for the circuit sampled voltage described interchange phase being detected higher than an overvoltage threshold (V
h) afterwards, one schedule time of time delay exports an overvoltage again and detects level,
In wherein said three over-voltage detection circuits, one of at least comprise voltage checking chip;
This device also comprises:
First gets or circuit (240), the output of the over-voltage detection circuit of voltage checking chip is asked to not comprising in the output of described three undervoltage detection circuits and described three over-voltage detection circuits or;
The first decision circuitry (250), gets or when circuit is output as described under-voltage detection level or described overvoltage and detects level output dropout trigger pip when described first;
Second gets or circuit (260), to the output of described the first decision circuitry and described in comprise the over-voltage detection circuit of voltage checking chip output ask or;
Dropout trigger circuit (270), get or circuit is output as described dropout trigger pip or described overvoltage and detects level when described second, trigger tripping coil and carry out the action of threading off.
As claimed in claim 1 under-voltage-overvoltage pick-up unit, wherein, described first get or circuit (240) to described three undervoltage detection circuits (220
1, 220
2, 220
3) output and a described over-voltage detection circuit (230
1) output get or.
As claimed in claim 1 under-voltage-overvoltage pick-up unit, wherein, the voltage checking chip comprising in described over-voltage detection circuit is the voltage checking chip with time delay.
As described in arbitrary in claim 1-3 under-voltage-overvoltage pick-up unit, wherein, described the first decision circuitry (250) is the voltage checking chip with time delay.
As claimed in claim 3 under-voltage-overvoltage pick-up unit, wherein, described undervoltage detection circuit comprises comparator circuit and delay circuit.
As claimed in claim 5 under-voltage-overvoltage pick-up unit, wherein, the delay circuit delay time in described undervoltage detection circuit is longer than the delay time of the voltage checking chip comprising in described over-voltage detection circuit.
7. under-voltage-over-pressure safety device, comprising:
Be connected to the isolating switch (130) in supply line;
The tripping coil (110) that can drive described isolating switch to disconnect;
At least one as described in arbitrary in claim 1-6 under-voltage-overvoltage pick-up unit, it is connected to described tripping coil (110), for there is overvoltage or when under-voltage on one of three-phase power line being detected, trigger described tripping coil and carry out de-mouthful, to drive described isolating switch to disconnect supply line.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210321607.0A CN103675416B (en) | 2012-09-03 | 2012-09-03 | Undervoltage-overvolprotection protection device and method |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210321607.0A CN103675416B (en) | 2012-09-03 | 2012-09-03 | Undervoltage-overvolprotection protection device and method |
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| Publication Number | Publication Date |
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| CN103675416A true CN103675416A (en) | 2014-03-26 |
| CN103675416B CN103675416B (en) | 2016-08-31 |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107017701A (en) * | 2017-06-12 | 2017-08-04 | 中山市中泰能科技有限公司 | A kind of solar energy uninterrupted power source management system |
| CN108387799A (en) * | 2018-03-06 | 2018-08-10 | 浙江宇视科技有限公司 | Over-pressed analysis system and device |
| CN109900957A (en) * | 2019-04-16 | 2019-06-18 | 上海艾为电子技术股份有限公司 | A kind of multiport chip with voltage detecting circuit |
| CN110865231A (en) * | 2019-12-09 | 2020-03-06 | 浙江中控技术股份有限公司 | Power supply voltage detection circuit for bus isolation |
| CN113589024A (en) * | 2020-04-30 | 2021-11-02 | 南京南瑞继保电气有限公司 | Method and device for rapidly detecting single set of abnormal alternating voltage measurement of redundant system |
| CN114295886A (en) * | 2021-12-07 | 2022-04-08 | 国网浙江省电力有限公司乐清市供电公司 | Processing device and processing circuit for high-voltage live alarm device |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2229112Y (en) * | 1995-01-12 | 1996-06-12 | 北京无线电技术研究所 | Multifunctional protector for electric appliance |
| CN1913272A (en) * | 2005-08-11 | 2007-02-14 | 艾默生网络能源系统有限公司 | Novel input undervoltage/overvoltage protection circuit |
| CN200987066Y (en) * | 2006-12-19 | 2007-12-05 | 欣灵电气股份有限公司 | Household line protector |
| CN101237137A (en) * | 2007-01-30 | 2008-08-06 | 鸿富锦精密工业（深圳）有限公司 | Over voltage and under-voltage device |
| US20090237187A1 (en) * | 2006-09-21 | 2009-09-24 | Daniel Gawendowicz | Auxiliary release for a circuit breaker |
| CN101697409A (en) * | 2009-10-22 | 2010-04-21 | 薛小平 | Voltage deviation action protecting device |
| CN202353175U (en) * | 2011-10-24 | 2012-07-25 | 西门子公司 | Overvoltage and undervoltage protection system for three-phase power system |
-
2012
- 2012-09-03 CN CN201210321607.0A patent/CN103675416B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2229112Y (en) * | 1995-01-12 | 1996-06-12 | 北京无线电技术研究所 | Multifunctional protector for electric appliance |
| CN1913272A (en) * | 2005-08-11 | 2007-02-14 | 艾默生网络能源系统有限公司 | Novel input undervoltage/overvoltage protection circuit |
| US20090237187A1 (en) * | 2006-09-21 | 2009-09-24 | Daniel Gawendowicz | Auxiliary release for a circuit breaker |
| CN200987066Y (en) * | 2006-12-19 | 2007-12-05 | 欣灵电气股份有限公司 | Household line protector |
| CN101237137A (en) * | 2007-01-30 | 2008-08-06 | 鸿富锦精密工业（深圳）有限公司 | Over voltage and under-voltage device |
| CN101697409A (en) * | 2009-10-22 | 2010-04-21 | 薛小平 | Voltage deviation action protecting device |
| CN202353175U (en) * | 2011-10-24 | 2012-07-25 | 西门子公司 | Overvoltage and undervoltage protection system for three-phase power system |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107017701A (en) * | 2017-06-12 | 2017-08-04 | 中山市中泰能科技有限公司 | A kind of solar energy uninterrupted power source management system |
| CN108387799A (en) * | 2018-03-06 | 2018-08-10 | 浙江宇视科技有限公司 | Over-pressed analysis system and device |
| CN109900957A (en) * | 2019-04-16 | 2019-06-18 | 上海艾为电子技术股份有限公司 | A kind of multiport chip with voltage detecting circuit |
| CN109900957B (en) * | 2019-04-16 | 2021-08-17 | 上海艾为电子技术股份有限公司 | Multi-port chip with voltage detection circuit |
| CN110865231A (en) * | 2019-12-09 | 2020-03-06 | 浙江中控技术股份有限公司 | Power supply voltage detection circuit for bus isolation |
| CN110865231B (en) * | 2019-12-09 | 2022-05-27 | 浙江中控技术股份有限公司 | Power supply voltage detection circuit for bus isolation |
| CN113589024A (en) * | 2020-04-30 | 2021-11-02 | 南京南瑞继保电气有限公司 | Method and device for rapidly detecting single set of abnormal alternating voltage measurement of redundant system |
| CN114295886A (en) * | 2021-12-07 | 2022-04-08 | 国网浙江省电力有限公司乐清市供电公司 | Processing device and processing circuit for high-voltage live alarm device |
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|---|---|
| CN103675416B (en) | 2016-08-31 |
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Inventor after: Bao Zhangyao Inventor after: Yang Lin Inventor after: Xiong Houyu Inventor before: Bao Zhangyao Inventor before: Yang Lin Inventor before: Xiong Yu |
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