CN201083789Y - Device for detecting DC far-conveyed power line on current unbalancing - Google Patents
Device for detecting DC far-conveyed power line on current unbalancing Download PDFInfo
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- CN201083789Y CN201083789Y CNU2007201749766U CN200720174976U CN201083789Y CN 201083789 Y CN201083789 Y CN 201083789Y CN U2007201749766 U CNU2007201749766 U CN U2007201749766U CN 200720174976 U CN200720174976 U CN 200720174976U CN 201083789 Y CN201083789 Y CN 201083789Y
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- power cable
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Abstract
The utility model discloses a device for detecting current unbalance of DC remote power line, aiming at resolving the problems that in the single power supply working mode, the current unbalance of the DC remote power line can be detected under the condition of not increasing costs. The device comprises a line pair sampling circuit, two one-way operational amplification circuits, a one-way comparator circuit and a control protective circuit; the device has the advantages of simple structure, small number of parts, low cost and good practicability; as a result, the utility model has a good market prospect.
Description
Technical field
The present invention relates to a kind of current sensing means, particularly relate to a kind of device that is applied to the detection direct current remote power cable of communication facilities to the current unevenness weighing apparatus.
Background technology
In the application project of circuit, people often need differentiate the amplitude size of two direct current signal differences, for example, in the direct current remote electric power system, we find that the signal wire of parallel transmission is to when transmitting dc energy, if some line is in the approach of transmission, insulation damages appears, the human body overlap joint, the circuit contact resistance changes when waiting situation greatly, because the power of far-end load is constant, it is serious unbalanced to cause the right electric current of the line of parallel transmission to occur, and the excessive line of electric current will be to the right damage of line occurring owing to the overcurrent heating, and make other line to chain damage fault occurring, thereby make the communication facilities power supply that the direct current remote power feeding system can't the bio-occlusion far-end.Therefore, we need in time line centering DC current difference to be detected and judge in the Remote Power Supply design and using, and when the amplitude that difference occurs surpassed setting value, system need alarm, protect.
In the decision circuitry of traditional signal difference amplitude size, generally be to adopt two-supply circuit to carry out, amplify as two paths of signals directly being carried out difference, this value has the characteristic of positive negative value, then, the window comparator that employing has bound compares, thereby whether the absolute value of judging difference transfinites; After perhaps difference being carried out full-bridge rectification, carry out single-ended amplitude more relatively, judge whether the absolute value of difference transfinites.
But in a lot of application circuits; often run into the situation of having only single supply; at this moment; the application of above-mentioned classic method is difficulty comparatively; unless single supply is transformed to dual power supply again powers; but this causes increasing considerably of circuit cost; therefore; the utility model has just designed a kind of single supply working method of adopting; can be applicable to the device of direct current remote power cable to the current unevenness weighing apparatus; to satisfy the alarm of line that the direct current Remote Power Supply occurs in engineering is used to the current unevenness weighing apparatus; the demand of protection; avoid the right damage of line occurring owing to the serious unbalanced overcurrent heating that causes appears in the right electric current of line; make other line to the fault of chain damage occurring subsequently, thereby guarantee the communication facilities power supply of direct current remote power feeding system bio-occlusion far-end.
Summary of the invention
The purpose of this utility model is to provide a kind of novel employing single supply working method, detects the protective device of direct current remote power cable to the current unevenness weighing apparatus.
In order to achieve the above object, the utility model is achieved in that the utility model is made up of current sampling circuit, two unidirectional operational amplification circuits, a unidirectional comparator circuit and a control protection electric circuit a line; Line is made up of DC/DC module, sampling resistor R1 and sampling resistor R2 current sampling circuit, sampling resistor R1, sampling resistor R2 are connected on respectively on the right common ground terminal of order wire, as of the sampling of two lines, obtain sampled voltage U1 and sampled voltage U2 respectively to last power supply; Control protection electric circuit plays the powered-down power circuit.
Two unidirectional operational amplification circuits are used for the amplified current difference; One of them unidirectional operational amplification circuit is made up of operational amplifier IC19A, input resistance R120, input resistance R121, enlargement factor associated resistance R110, enlargement factor associated resistance R122, filter capacitor C116, single-phase isolating diode D55; Another unidirectional operational amplification circuit is made up of operational amplifier IC19B, input resistance R96, input resistance R97, enlargement factor associated resistance R98, enlargement factor associated resistance R107, filter capacitor C104, single-phase isolating diode D51.
A unidirectional comparator circuit is made up of comparer IC18A, reference voltage have a resistance R118, input resistance R118A, the capacitor C 114 of R117, reference voltage that have a resistance, and is used for the threshold value of electric current difference is judged.
What the utility model adopted is the single supply circuit.
The utility model device has following technical characterstic:
1, adopts the mode of operation of single supply, can realize the detection of absolute difference;
2, adopt two unilateral diodes, realized selecting of absolute value signal;
3, line construction is succinct, and the components and parts number is few;
4, select the parameter of suitable pre-amplifier, this device can be fit to any two the difference detection and judgements of earth signal altogether.
Description of drawings
Below in conjunction with drawings and Examples the utility model is further specified.
Fig. 1 is that direct current Remote Power Supply and line are to the current sampling circuit synoptic diagram;
Fig. 2 is the utility model circuit diagram.
Among the figure: the 1-line is to current sampling circuit; 2, the unidirectional operational amplification circuit of 3-; The unidirectional computing comparator circuit of 4-; The 5-control protection electric circuit.
Embodiment
As depicted in figs. 1 and 2, the utility model is made up of current sampling circuit 2,3, one unidirectional comparator circuits 4 of 1, two unidirectional operational amplification circuit and a control protection electric circuit 5 line.
In Fig. 1, the direct current output of local side DC/DC power module is right by the order wire of two-way, being transferred to far-end respectively powers to communication facilities, sampling resistor R1, sampling resistor R2 are connected on respectively on the right common ground terminal of order wire, as to of the sampling of two lines, can obtain sampled voltage U1 and sampled voltage U2 respectively like this to last electric current.
In Fig. 2, sampled voltage U1, sampled voltage U2 deliver to the 3. 2. pin of pin and of operational amplifier IC19A respectively by input resistance R120, input resistance R121, through operational amplifier IC19A, operational amplifier IC19A the 1. pin obtain to be proportional to the voltage of sampled voltage U1 and sampled voltage U2 difference; In like manner, sampled voltage U2, sampled voltage U1 deliver to the 5. 6. pin of pin and of operational amplifier IC19B respectively by input resistance R96, input resistance R97, through behind the operational amplifier IC19B, operational amplifier IC19B the 7. pin obtain to be proportional to the voltage of sampled voltage U2 and sampled voltage U1 difference; 1. 7. in this magnitude of voltage of 2 of pin of pin and operational amplifier IC19B of operational amplifier IC19A, always have one be 0 value or on the occasion of, on the occasion of voltage can deliver to the 3. pin of comparer IC18A by single-phase isolating diode D51, single-phase isolating diode D55.Reference voltage R117, the reference voltage R118 that has a resistance that has a resistance forms bleeder circuit, in the reference voltage input that 2. produces comparer on the pin of comparer IC18A; When the right electric current difference of two lines is less, deliver to comparer IC18A 3. the level of pin less than the 2. level of pin of comparer IC18A, thereby the 1. pin output low level of comparer IC18A is delivered to control protection electric circuit 5 with signal; When two right electric current differences of line reach set point; deliver to comparer IC18A the 3. the level of pin just surpass the 2. level of pin of comparer IC18A; thereby comparer IC18A 1. pin be changed to high level by low level; make control protection electric circuit 5 receive the signal of alarm, protection action, eliminate possible line fault.Online on do not have electric current to flow through, when perhaps the right electric current difference of two lines is recovered less than the protection point set, comparer IC18A the 1. pin with output low level, the signal cancellation that alarm and protection are moved.
What the utility model adopted is the single supply circuit.
The utility model can also be applied in other occasion, as can be used for two excessive occasions of signal difference of comparison, the problem that elimination may cause.
Claims (7)
1. one kind is used to detect the device of direct current remote power cable to current imbalance, comprising a line to a sample circuit (1) and a control protection electric circuit (5); Line is made up of DC/DC module, sampling resistor R1 and sampling resistor R2 sample circuit (1), sampling resistor R1, sampling resistor R2 are connected on respectively on the right common ground terminal of order wire, as of the sampling of two lines, obtain sampled voltage U1 and sampled voltage U2 respectively to last electric current; Control protection electric circuit (5) plays the powered-down power circuit;
It is characterized in that:
This device also comprises two unidirectional operational amplification circuits (2,3), is used for the amplified current difference; A unidirectional comparator circuit (4) is judged the threshold value of electric current difference.
2. a kind of device of direct current remote power cable that be used to detect according to claim 1 to current imbalance, the unidirectional operational amplification circuit (2) in this device is made up of operational amplifier IC19A, input resistance R120, input resistance R121, enlargement factor associated resistance R110, enlargement factor associated resistance R122, filter capacitor C116, single-phase isolating diode D55; Another unidirectional operational amplification circuit (3) is made up of operational amplifier IC19B, input resistance R96, input resistance R97, enlargement factor associated resistance R98, enlargement factor associated resistance R107, filter capacitor C104, single-phase isolating diode D51.
3. a kind of device of direct current remote power cable that be used to detect according to claim 1 and 2 to current imbalance, unidirectional comparator circuit (4) in this device is made up of comparer IC18A, reference voltage have a resistance R118, input resistance R118A, the capacitor C 114 of R117, reference voltage that have a resistance, and is used for the threshold value of electric current difference is judged.
4. according to the right 3 described a kind of devices of direct current remote power cable to current imbalance that are used to detect, what this device adopted is the single supply circuit, realizes detecting the imbalance of direct current remote power cable to electric current.
5. a kind of device of direct current remote power cable to current imbalance that be used to detect according to claim 3, this device can be used for two excessive occasions of signal difference of comparison.
6. according to right 1 or the 2 described a kind of devices of direct current remote power cable to current imbalance that are used to detect, what this device adopted is the single supply circuit, realizes detecting the imbalance of direct current remote power cable to electric current.
7. a kind of device of direct current remote power cable to current imbalance that be used to detect according to claim 1 and 2, this device can be used for two excessive occasions of signal difference of comparison.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU2007201749766U CN201083789Y (en) | 2007-09-14 | 2007-09-14 | Device for detecting DC far-conveyed power line on current unbalancing |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU2007201749766U CN201083789Y (en) | 2007-09-14 | 2007-09-14 | Device for detecting DC far-conveyed power line on current unbalancing |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN201083789Y true CN201083789Y (en) | 2008-07-09 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNU2007201749766U Expired - Lifetime CN201083789Y (en) | 2007-09-14 | 2007-09-14 | Device for detecting DC far-conveyed power line on current unbalancing |
Country Status (1)
| Country | Link |
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| CN (1) | CN201083789Y (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102135784A (en) * | 2010-01-21 | 2011-07-27 | 鸿富锦精密工业（深圳）有限公司 | Current balance circuit |
| CN103149417A (en) * | 2013-01-30 | 2013-06-12 | 北京信诺达泰思特科技股份有限公司 | Circuit measuring module and method for measuring voltage difference of power source device |
| CN104298641A (en) * | 2009-03-30 | 2015-01-21 | 美国亚德诺半导体公司 | USB isolator with advanced control features |
| CN106706996A (en) * | 2015-11-18 | 2017-05-24 | 上海航天汽车机电股份有限公司 | Motor current detection signal amplifying circuit |
| CN109581029A (en) * | 2018-12-05 | 2019-04-05 | 郑州云海信息技术有限公司 | A kind of system for detecting multi input end current balance type |
| CN110691976A (en) * | 2017-06-29 | 2020-01-14 | 华为技术有限公司 | Remote power supply module, direct-current power system and fault detection method of direct-current power system |
-
2007
- 2007-09-14 CN CNU2007201749766U patent/CN201083789Y/en not_active Expired - Lifetime
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104298641A (en) * | 2009-03-30 | 2015-01-21 | 美国亚德诺半导体公司 | USB isolator with advanced control features |
| CN102135784A (en) * | 2010-01-21 | 2011-07-27 | 鸿富锦精密工业（深圳）有限公司 | Current balance circuit |
| CN102135784B (en) * | 2010-01-21 | 2014-11-26 | 国网山西省电力公司长治供电公司 | Current balance circuit |
| CN103149417A (en) * | 2013-01-30 | 2013-06-12 | 北京信诺达泰思特科技股份有限公司 | Circuit measuring module and method for measuring voltage difference of power source device |
| CN106706996A (en) * | 2015-11-18 | 2017-05-24 | 上海航天汽车机电股份有限公司 | Motor current detection signal amplifying circuit |
| CN110691976A (en) * | 2017-06-29 | 2020-01-14 | 华为技术有限公司 | Remote power supply module, direct-current power system and fault detection method of direct-current power system |
| CN110691976B (en) * | 2017-06-29 | 2021-03-23 | 华为技术有限公司 | Remote power supply module, direct-current power system and fault detection method of direct-current power system |
| US11374395B2 (en) | 2017-06-29 | 2022-06-28 | Huawei Technologies Co., Ltd. | Remote power unit, direct current power system and direct current power system fault detection method |
| CN109581029A (en) * | 2018-12-05 | 2019-04-05 | 郑州云海信息技术有限公司 | A kind of system for detecting multi input end current balance type |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CX01 | Expiry of patent term | ||
| CX01 | Expiry of patent term |
Granted publication date: 20080709 |