CN203870150U - Isolation type power grid detector - Google Patents
Isolation type power grid detector Download PDFInfo
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- CN203870150U CN203870150U CN201420315131.4U CN201420315131U CN203870150U CN 203870150 U CN203870150 U CN 203870150U CN 201420315131 U CN201420315131 U CN 201420315131U CN 203870150 U CN203870150 U CN 203870150U
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- optocoupler
- operational amplifier
- input end
- output terminal
- feedback
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Abstract
The utility model relates to an isolation type power grid detector comprising a feedback electrode and an output electrode; the feedback electrode comprises a first operation amplifier, a first optical coupler, a second optical coupler and a first feedback resistor; an output end of the first operation amplifier is connected with a photoelectric current input end of the first optical coupler; a photoelectric current output end of the first optical coupler is connected with a photoelectric current input end of the second optical coupler; a photoelectric current output end of the second optical coupler is grounded; an induced-current output end is connected with an inverted input end of the first operation amplifier; the first feedback resistor is connected between the inverted input end of the first operation amplifier and a grounding line; the output electrode comprises a second operation amplifier and a second feedback resistor. The isolation type power grid detector has isolation function, and isolated output voltage is in proportion to the input voltage; voltage and current signals needing to be isolated can be detected; the isolation type power grid detector is simple in structure, low in cost, high in precision, and good in linearity.
Description
Technical field
The utility model relates to electronic circuit field, particularly, relates to a kind of isolated electrical network detecting device.
Background technology
Along with the development of power technology, in electric system, communication system, use more and more widely the power-supply device such as Switching Power Supply, UPS.These equipment will detect voltage, the current signal of main circuit bar none.Testing circuit is the interface of main circuit and control circuit, is the requisite important component part of power-supply device.Testing circuit must meet the requirement of following several respects:
(1) to there be very high precision and the linearity.Modern power supply, in order to reach very high voltage stabilization and current stabilization precision and to have good dynamic response characteristic, is all introduced the FEEDBACK CONTROL of electric current and voltage participation system mostly.The precision of testing circuit and the linearity, determined output accuracy and the stability of whole power supply to a certain extent.
(2) must there is isolation features.Between the main circuit of most of power supplys and control circuit on electric mutually insulated.Otherwise power supply can be due to the interference of main circuit to control circuit and cisco unity malfunction, even entail dangers to commissioning staff's personal safety.
At present, on market, existing isolation detector is as isolated amplifier, voltage Hall, current Hall etc., and how very expensive price is, and feedback linearization degree is poor.
Utility model content
Expensive for overcoming existing isolation detector, the technological deficiency that feedback linearization degree is poor, the utility model discloses a kind of isolated electrical network detecting device.
Isolated electrical network detecting device described in the utility model, formed by feedback stage and output stage, described feedback stage comprises the first operational amplifier, the first optocoupler, the second optocoupler and the first feedback resistance, the first operational amplifier output terminal connects the photocurrent input end of the first optocoupler, the photocurrent output terminal of described the first optocoupler connects the photocurrent input end of the second optocoupler, the photocurrent output head grounding of described the second optocoupler, induction current output terminal connects the inverting input of the first operational amplifier, described the first feedback resistance is connected between the inverting input and ground wire of the first operational amplifier,
Described output stage comprises the second operational amplifier and the second feedback resistance, the normal phase input end of described the second operational amplifier connects the induction current output terminal of the first optocoupler, the inverting input of the second operational amplifier is connected with output terminal, and described the second feedback resistance is connected between the normal phase input end and ground of the second operational amplifier.
Preferably, described the first operational amplifier output terminal connects between the photocurrent input end of photocurrent input end the first optocoupler of the first optocoupler and is connected with current-limiting resistance.
Preferably, between described the first operational amplifier output terminal and inverting input, be connected with building-out capacitor.
Preferably, described the first optocoupler is identical with the model of the second optocoupler.
Preferably, the normal phase input end of described the first operational amplifier is connected with gate protection resistance.
Isolated electrical network detecting device described in the utility model, has isolation features, and isolation after output voltage be directly proportional to input voltage, can be used for detect needs isolate voltage, current signal.By the extremely low common separation device of use cost, significantly reduce manufacturing cost, there is simple in structure, low price, precision is high, the linearity is good feature.
Brief description of the drawings
Fig. 1 is a kind of embodiment schematic diagram of the utility model;
Mark and corresponding parts title in accompanying drawing: IN-test side, R1-current-limiting resistance, R2-the first feedback resistance; R3-the second feedback resistance; R4-gate protection resistance, C-building-out capacitor, AMP1-the first operational amplifier; AMP2-the second operational amplifier; G1 – the first optocoupler, G2-the second optocoupler, D-optocoupler luminotron; T-optocoupler inductive output tube VCC-direct supply, OUT-signal output part.
Embodiment
Below in conjunction with embodiment and accompanying drawing, the utility model is done to detailed description further, but embodiment of the present utility model is not limited to this.
Isolated electrical network detecting device described in the utility model, formed by feedback stage and output stage, described feedback stage comprises the first operational amplifier A MP1, the first optocoupler G1, the second optocoupler G2 and the first feedback resistance R2, the first operational amplifier output terminal connects the photocurrent input end of the first optocoupler, the photocurrent output terminal of described the first optocoupler connects the photocurrent input end of the second optocoupler, the photocurrent output head grounding of described the second optocoupler, induction current output terminal connects the inverting input of the first operational amplifier, described the first feedback resistance is connected between the inverting input and ground wire of the first operational amplifier,
Described output stage comprises the second operational amplifier and the second feedback resistance, the normal phase input end of described the second operational amplifier connects the induction current output terminal of the first optocoupler, the inverting input of the second operational amplifier is connected with output terminal, and described the second feedback resistance is connected between the normal phase input end and ground of the second operational amplifier.
As shown in Figure 1, optocoupler in dotted line frame is made up of optocoupler luminotron D and optocoupler inductive output tube T, the electric current of operational amplifier output flows into from photocurrent input end, D is luminous for optocoupler luminotron, luminous flux is responded to by optocoupler inductive output tube, generation current, the power end of the optocoupler inductive output tube of each optocoupler connects external direct supply VCC.
The effect of two optocouplers is one, and as output, another is as feedback, and the first optocoupler is for compensating the non-linear of light emitting diode time, temperature characterisitic.In order to ensure that the luminous flux that second output signal of optocoupler generation and the luminotron of the first optocoupler send is linear scaling, in the time of selector, the characteristic of two photo-couplers should be consistent as far as possible, should preferably select the optocoupler that model is consistent.
When detection, the normal phase input end of the first operational amplifier A MP1 is connected with detected signal, signal is inputted from test side IN, in testing circuit adjustment process, detection signal has two kinds of variation tendencies, to detect voltage as example, in the time that input voltage Ui raises, make Ui>R2*I2, I2 is the electric current from the second optocoupler photocurrent output terminal output, cause the output end voltage of the first operational amplifier to raise, electric current I 1 by luminotron in optocoupler also increases thereupon, the luminotron of two optocouplers forms series relationship, therefore I2=K1*I1, I3=K2*I1, wherein K1, K2 is respectively the induction coefficient of two optocouplers, I2, I3 also increases, I3 is the electric current that flows through the second feedback resistance R3, two operational amplifiers are negative feedback type of attachment, two input terminal voltages equate respectively, can obtain the output voltage U O=(K1*R3/K2*R2 at signal output part OUT) * Ui, UO is linear increase along with the increase of Ui.
Otherwise in the time that input voltage Ui reduces, the output end voltage of the first operational amplifier reduces, also reduce by the electric current I 1 of luminotron in optocoupler thereupon, with upper similar, output voltage is also with proportional the reducing of reduction of input voltage Ui.
Can between connecting the photocurrent input end of photocurrent input end the first optocoupler of the first optocoupler, described the first operational amplifier output terminal connect current-limiting resistance R1, avoid the input current of optocoupler to exceed the linear threshold scope of luminotron, because utilizing the luminous flux of the luminotron in optocoupler, the utility model is directly proportional to the electric current flowing through, therefore input current must change in linear threshold range, with current increases, the substantially linear growth of the luminous flux of luminotron.
A more excellent selection is between the first operational amplifier output terminal and inverting input, to connect building-out capacitor C, the utility model is applied to detection AC network, clutter disorder, connect building-out capacitor C, for the first operational amplifier provides a dominant pole, improved the closed loop stability of the first operational amplifier, the value of building-out capacitor C can be in nanofarad to microfarad rank, for example 1-1000 nanofarad.Can also connect gate protection resistance R 4 at the normal phase input end of the first operational amplifier; because test side IN is directly connected with external belt detection of grid; electric current and voltage value is all difficult to calculate; preferably IN end connects gate protection resistance R 4; R4 value at thousands of ohm, can play certain protective effect conventionally.
As mentioned above, can realize preferably the utility model.
Claims (5)
1. isolated electrical network detecting device, it is characterized in that, formed by feedback stage and output stage, described feedback stage comprises the first operational amplifier, the first optocoupler, the second optocoupler and the first feedback resistance, the first operational amplifier output terminal connects the photocurrent input end of the first optocoupler, the photocurrent output terminal of described the first optocoupler connects the photocurrent input end of the second optocoupler, the photocurrent output head grounding of described the second optocoupler, induction current output terminal connects the inverting input of the first operational amplifier, described the first feedback resistance is connected between the inverting input and ground wire of the first operational amplifier,
Described output stage comprises the second operational amplifier and the second feedback resistance, the normal phase input end of described the second operational amplifier connects the induction current output terminal of the first optocoupler, the inverting input of the second operational amplifier is connected with output terminal, and described the second feedback resistance is connected between the normal phase input end and ground of the second operational amplifier.
2. isolated electrical network detecting device according to claim 1, is characterized in that, described the first operational amplifier output terminal connects between the photocurrent input end of photocurrent input end the first optocoupler of the first optocoupler and is connected with current-limiting resistance.
3. isolated electrical network detecting device according to claim 1, is characterized in that, between described the first operational amplifier output terminal and inverting input, is connected with building-out capacitor.
4. isolated electrical network detecting device according to claim 1, is characterized in that, described the first optocoupler is identical with the model of the second optocoupler.
5. isolated electrical network detecting device according to claim 1, is characterized in that, the normal phase input end of described the first operational amplifier is connected with gate protection resistance.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420315131.4U CN203870150U (en) | 2014-06-14 | 2014-06-14 | Isolation type power grid detector |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420315131.4U CN203870150U (en) | 2014-06-14 | 2014-06-14 | Isolation type power grid detector |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN203870150U true CN203870150U (en) | 2014-10-08 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201420315131.4U Expired - Fee Related CN203870150U (en) | 2014-06-14 | 2014-06-14 | Isolation type power grid detector |
Country Status (1)
| Country | Link |
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| CN (1) | CN203870150U (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104931814A (en) * | 2015-05-23 | 2015-09-23 | 成都众孚理想科技有限公司 | Digital isolation type grid detector |
| CN108045256A (en) * | 2017-12-26 | 2018-05-18 | 深圳深宝电器仪表有限公司 | A kind of charging system for electric automobile and charging pile |
| CN113285709A (en) * | 2021-05-07 | 2021-08-20 | 成都军陶科技有限公司 | Linear optical coupling circuit |
-
2014
- 2014-06-14 CN CN201420315131.4U patent/CN203870150U/en not_active Expired - Fee Related
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104931814A (en) * | 2015-05-23 | 2015-09-23 | 成都众孚理想科技有限公司 | Digital isolation type grid detector |
| CN104931814B (en) * | 2015-05-23 | 2018-01-26 | 成都众孚理想科技有限公司 | A kind of isolated power network detector of numeral |
| CN108045256A (en) * | 2017-12-26 | 2018-05-18 | 深圳深宝电器仪表有限公司 | A kind of charging system for electric automobile and charging pile |
| CN108045256B (en) * | 2017-12-26 | 2023-11-03 | 深圳深宝电器仪表有限公司 | Electric automobile charging system and fill electric pile |
| CN113285709A (en) * | 2021-05-07 | 2021-08-20 | 成都军陶科技有限公司 | Linear optical coupling circuit |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20141008 Termination date: 20200614 |
|
| CF01 | Termination of patent right due to non-payment of annual fee |