CN101923111A - Isolation detection circuit of DC bus voltage - Google Patents

Isolation detection circuit of DC bus voltage Download PDF

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Publication number
CN101923111A
CN101923111A CN 200910303162 CN200910303162A CN101923111A CN 101923111 A CN101923111 A CN 101923111A CN 200910303162 CN200910303162 CN 200910303162 CN 200910303162 A CN200910303162 A CN 200910303162A CN 101923111 A CN101923111 A CN 101923111A
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optocoupler
amplifier
voltage
detection circuit
feedback control
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CN 200910303162
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CN101923111B (en
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裘锦灼
周海亮
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Nideke (beijing) Transmission Technology Co Ltd
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Beijing China Tex Mechanical & Electrical Engineering Ltd
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Abstract

The invention discloses an isolation detection circuit of DC bus voltage, which comprises optical coupling elements and single-power dual-operational amplifiers. The output phototriodes of the two optical coupling elements BG1 and BG2 are connected in series, and the connection point is connected with the in-phase or out-phase input end of the first operational amplifier U1 to supply power at a low-voltage side through a DC power supply +E; one of the optical coupling elements is a detection optocoupler BG1, and the LED thereof is serially connected with a high-voltage resistor R1 to detect the DC bus voltage; the other one of the optical coupling elements is a feedback control optocoupler BG2; the two input ends of the operational amplifier U1 are connected with the opposite angles of the electrical bridge of equal-arm resistors R3, R4, R5 and R6 powered by the DC power supply, and the output of the operational amplifier U1 is serially connected with the LED of the feedback optocoupler; and the input current of the feedback optocoupler is converted into voltage through a resistor R7 and subjected to in-phase amplification by the operational amplifier U2 before output. The invention provides a new method for detecting a DC bus, which has the advantages of simple circuit, low cost, high measurement precision, good isolation effect and broad popularization and application prospect.

Description

Isolation detection circuit of DC bus voltage
Technical field
The present invention relates to a kind of voltage detecting circuit, specifically, relate to the isolation detection circuit of main circuit DC bus-bar voltage in a kind of SRM (switched reluctance motor) speed regulating device and the variable-frequency motor speed governing.
Background technology
In SRM (switched reluctance motor) speed regulating device, power inversion circuit is by the DC bus-bar voltage power supply.This is the output voltage of three-phase bridge rectification power supply, is parallel with suitable filter capacitor above.After AC network was closed a floodgate, DC bus-bar voltage rose at leisure through current-limiting resistance earlier, and then the current-limiting resistance short circuit.Have only DC bus-bar voltage to reach enough big numerical value, just allow power inversion circuit work.
If motor is in generating state, DC bus-bar voltage can further rise, its value even greater than the peak value of three-phase electricity netting twine voltage, and the result disconnects the diode of rectifier bridge.When after this having arrived License Value, just need to connect special power switch,, perhaps electric energy is fed back to electrical network conductive discharge.
DC bus-bar voltage is an important parameters very, must detect timely, and will isolate reliably between output signal and dc bus could be safer.
About the isolation detection of DC bus-bar voltage, existing product is made of Hall element, and this product inside must have the number of turn a lot, the magnetic test coil that lead is very thin, the coiling trouble, and its input current is still bigger, the powerful resistance of need connecting when detecting high voltage, small product size is big, and price is higher.
Easier detection scheme is to use linear optical coupling, and its principle as shown in Figure 1.Two photodiodes of linear optical coupling output match mutually, shone by same light emitting diode; Flow through the output current of first amplifier in light emitting diode, a photodiode is made negative feedback usefulness to amplifier, and the another photodiode is then as the input of the amplifier of second isolation that amplifier constitutes.
Need be except the dc bus side with amplifier of isolating and the accessory power supply, also there is a big shortcoming in the linear optical coupling scheme, is exactly that electric current in the output light emitting diode is very little, poor anti jamming capability when detecting DC bus-bar voltage, the detection error ratio is bigger.
Summary of the invention
A kind of isolation detection circuit of DC bus voltage that the present invention designs in order to solve the problems of the technologies described above just.
The technical solution adopted for the present invention to solve the technical problems is:
A kind of isolation detection circuit of DC bus voltage comprises optical coupling element, single supply type dual operational amplifier; The output phototriode series connection of two optical coupling element BG1, BG2, tie point is connected to homophase or the inverting input of first amplifier U1, powers in low-pressure side by a direct supply+E; One is detected DC bus-bar voltage for detecting optocoupler BG1 behind its light emitting diode series connection high-tension resistive R1 in the optical coupling element, and the another optical coupling element is FEEDBACK CONTROL optocoupler BG2; Two input ends of an amplifier U1 are connected to the diagonal angle by the equiarm resistance R 3 of direct supply+E power supply, R4, R5, R6 electric bridge, the light emitting diode of the output serial Feedback optocoupler BG1 of amplifier U1; By resistance R 7 input current of feedback optocoupler BG1 is converted to voltage, make homophase through another amplifier U2 then and amplify output.
Described isolation detection circuit of DC bus voltage, it detects the emitter of optocoupler BG1 and the collector of FEEDBACK CONTROL optocoupler BG2 links, and is connected to the in-phase input end of amplifier U1; The collector that detects optocoupler BG1 connects+the E power positive end; The emitter of FEEDBACK CONTROL optocoupler BG2 connects+the E power supply negative terminal.
Described isolation detection circuit of DC bus voltage, it detects the collector of optocoupler BG1 and the emitter of FEEDBACK CONTROL optocoupler BG2 links, and is connected to the inverting input of amplifier U1; The emitter that detects optocoupler BG1 connects+the E power supply negative terminal; The collector of FEEDBACK CONTROL optocoupler BG2 connects+the E power positive end.
Described isolation detection circuit of DC bus voltage, its model, specification that detects optocoupler BG1 and FEEDBACK CONTROL optocoupler BG2 is identical, and the transfer ratio pairing; Resistance decision by high-tension resistive R1 detects range, between the light emitting diode of detection optocoupler and phototriode higher withstand voltage is arranged, when FEEDBACK CONTROL optocoupler BG2 is operated in input full scale voltage, and is added with and flows out electric current in two optocoupler phototriodes of 1/2 direct current supply voltage and differ 10% at most.
Described isolation detection circuit of DC bus voltage, it can set the output voltage of testing circuit full scale by the resistance of adjusting resistance R 7 and the enlargement factor of in-phase amplifier U2.
Described isolation detection circuit of DC bus voltage, it detects resistance in series R2 on the light emitting diode of optocoupler BG1, and on both series circuits shunt capacitance C1, but elimination pulsating volage and burr; Capacitor C 2 connects amplifier U1 output terminal and inverting input, eliminates amplifier U1 and goes up the spurious oscillation that produces.
The present invention is the new isolation detection circuit of a kind of DC bus-bar voltage, and main devices is two to be exported with phototriode, optocoupler and a single supply type double operational of transfer ratio pairing.Only power in low-pressure side by a direct supply.Circuit is simple, and accuracy of detection and isolation effect are good, is used for switched reluctance motor and adjustable frequency motor arrangements for speed regulation.
The invention has the beneficial effects as follows: the invention provides a kind of new method that detects dc bus, circuit is simple, and cost is low, and measuring accuracy and isolation effect are good, can be widely used in switched reluctance motor and adjustable frequency motor arrangements for speed regulation, popularizing application prospect is long-range.
Description of drawings
Fig. 1 detects the circuit diagram of DC bus-bar voltage for the linear optical coupling scheme.
Fig. 2 is an embodiment of the present invention DC bus-bar voltage testing circuit figure.
The another kind of embodiment DC bus-bar voltage of Fig. 3 the present invention testing circuit figure.
Embodiment
The present invention is further described below in conjunction with drawings and Examples.
A kind of isolation detection circuit of DC bus voltage shown in Fig. 2 and 3 comprises optical coupling element, single supply type dual operational amplifier; The output phototriode series connection of two optical coupling element BG1, BG2, tie point is connected to homophase or the inverting input of first amplifier U1, powers in low-pressure side by a direct supply+E; One is detected DC bus-bar voltage for detecting optocoupler BG1 behind its light emitting diode series connection high-tension resistive R1 in the optical coupling element, and the another optical coupling element is FEEDBACK CONTROL optocoupler BG2; Two input ends of an amplifier U1 are connected to the diagonal angle by the equiarm resistance R 3 of direct supply+E power supply, R4, R5, R6 electric bridge, the light emitting diode of the output serial Feedback optocoupler BG1 of amplifier U1; By resistance R 7 input current of feedback optocoupler BG1 is converted to voltage, make homophase through another amplifier U2 then and amplify output.
Described isolation detection circuit of DC bus voltage, it detects the emitter of optocoupler BG1 and the collector of FEEDBACK CONTROL optocoupler BG2 links, and is connected to the in-phase input end of amplifier U1; The collector that detects optocoupler BG1 connects+the E power positive end; The emitter of FEEDBACK CONTROL optocoupler BG2 connects+the E power supply negative terminal.
Described isolation detection circuit of DC bus voltage, it detects the collector of optocoupler BG1 and the emitter of FEEDBACK CONTROL optocoupler BG2 links, and is connected to the inverting input of amplifier U1; The emitter that detects optocoupler BG1 connects+the E power supply negative terminal; The collector of FEEDBACK CONTROL optocoupler BG2 connects+the E power positive end.
Described isolation detection circuit of DC bus voltage, its model, specification that detects optocoupler BG1 and FEEDBACK CONTROL optocoupler BG2 is identical, and the transfer ratio pairing; Resistance decision by high-tension resistive R1 detects range, between the light emitting diode of detection optocoupler and phototriode higher withstand voltage is arranged, when FEEDBACK CONTROL optocoupler BG2 is operated in input full scale voltage, and is added with and flows out electric current in two optocoupler phototriodes of 1/2 direct current supply voltage and differ 10% at most.
Described isolation detection circuit of DC bus voltage, it can set the output voltage of testing circuit full scale by the resistance of adjusting resistance R 7 and the enlargement factor of in-phase amplifier U2.
Described isolation detection circuit of DC bus voltage, it detects resistance in series R2 on the light emitting diode of optocoupler BG1, and on both series circuits shunt capacitance C1, but elimination pulsating volage and burr; Capacitor C 2 connects amplifier U1 output terminal and inverting input, eliminates amplifier U1 and goes up the spurious oscillation that produces.
Be illustrated in figure 2 as a kind of embodiment of preferential recommendation.After the output phototriode of two optocouplers was together in series, tie point was connected to the in-phase input end of first amplifier.
The present invention has used an optocoupler to detect, and its light emitting diode series connection high-tension resistive detects DC bus-bar voltage, and the electric current that flows through light emitting diode is little, by the range of high-tension resistive resistance decision detection.In fact high-tension resistive can be one or by some series connection, resistor power and withstand voltagely all enough allowances will be arranged.Between the light emitting diode of detection optocoupler BG1 and the phototriode enough withstand voltage allowance should be arranged.
Another optocoupler of the present invention is made FEEDBACK CONTROL, and model, the specification of FEEDBACK CONTROL optocoupler BG2 are the same with the detection optocoupler, and transfer ratio will be matched.When input full scale voltage pairing electric current, be added with and flow out electric current in two optocoupler phototriodes of 1/2 direct current supply voltage and differ 10% at most.
The light emitting diode string of feedback optocoupler BG1 is in the output of first amplifier U1, and under normal circumstances, the output current of feedback optocoupler BG1 should equal to detect the output current of optocoupler, therefore feeds back optocoupler and detects that input current at most also only differs 10% between optocoupler.
The another kind of embodiment of testing circuit of the present invention as shown in Figure 3, the output phototriode tie point of two optocouplers is connected to the inverting input of first amplifier, the feedback optocoupler all plays the negative feedback control action in two kinds of connections.
In Fig. 2 and Fig. 3 circuit, the input current of feedback optocoupler is converted to voltage, make homophase by second amplifier then and amplify also final output with a resistance.Suitably regulate resistance value and homophase enlargement factor, just can set up the output voltage of testing circuit full scale.Resistance value is fixed among the figure, and the homophase enlargement factor is then regulated by potentiometer.

Claims (6)

1. an isolation detection circuit of DC bus voltage comprises optical coupling element, single supply type dual operational amplifier; It is characterized in that: the output phototriode series connection of two optical coupling element BG1, BG2, tie point is connected to homophase or the inverting input of first amplifier U1, powers in low-pressure side by a direct supply+E; One is detected DC bus-bar voltage for detecting optocoupler BG1 behind its light emitting diode series connection high-tension resistive R1 in the optical coupling element, and the another optical coupling element is FEEDBACK CONTROL optocoupler BG2; Two input ends of an amplifier U1 are connected to the diagonal angle by the equiarm resistance R 3 of direct supply+E power supply, R4, R5, R6 electric bridge, the light emitting diode of the output serial Feedback optocoupler BG1 of amplifier U1; By resistance R 7 input current of feedback optocoupler BG1 is converted to voltage, make homophase through another amplifier U2 then and amplify output.
2. isolation detection circuit of DC bus voltage according to claim 1 is characterized in that: detect the emitter of optocoupler BG1 and the collector of FEEDBACK CONTROL optocoupler BG2 and link, be connected to the in-phase input end of amplifier U1; The collector that detects optocoupler BG1 connects+the E power positive end; The emitter of FEEDBACK CONTROL optocoupler BG2 connects+the E power supply negative terminal.
3. isolation detection circuit of DC bus voltage according to claim 1 is characterized in that: detect the collector of optocoupler BG1 and the emitter of FEEDBACK CONTROL optocoupler BG2 and link, be connected to the inverting input of amplifier U1; The emitter that detects optocoupler BG1 connects+the E power supply negative terminal; The collector of FEEDBACK CONTROL optocoupler BG2 connects+the E power positive end.
4. isolation detection circuit of DC bus voltage according to claim 1 is characterized in that: the model, the specification that detect optocoupler BG1 and FEEDBACK CONTROL optocoupler BG2 are identical, and the transfer ratio pairing; Resistance decision by high-tension resistive R1 detects range, between the light emitting diode of detection optocoupler and phototriode higher withstand voltage is arranged, when FEEDBACK CONTROL optocoupler BG2 is operated in input full scale voltage, and is added with and flows out electric current in two optocoupler phototriodes of 1/2 direct current supply voltage and differ 10% at most.
5. isolation detection circuit of DC bus voltage according to claim 1 is characterized in that: by the resistance of adjusting resistance R 7 and the enlargement factor of in-phase amplifier U2, can set the output voltage of testing circuit full scale.
6. isolation detection circuit of DC bus voltage according to claim 1 is characterized in that: detect resistance in series R2 on the light emitting diode of optocoupler BG1, and on both series circuits shunt capacitance C1, but elimination pulsating volage and burr; Capacitor C 2 connects amplifier U1 output terminal and inverting input, eliminates amplifier U1 and goes up the spurious oscillation that produces.
CN 200910303162 2009-06-11 2009-06-11 Isolation detection circuit of DC bus voltage Expired - Fee Related CN101923111B (en)

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Cited By (19)

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CN102104319A (en) * 2011-04-01 2011-06-22 欧瑞传动电气有限公司 IGBT drive circuit and control method
CN102967748A (en) * 2012-11-12 2013-03-13 宁波韵升股份有限公司 DC bus voltage detection circuit with high antijamming capability
CN103023331A (en) * 2011-09-28 2013-04-03 中国科学院微电子研究所 Isolated voltage and current detection control circuit of high-voltage switch power supply
CN103023328A (en) * 2011-09-28 2013-04-03 中国科学院微电子研究所 Isolated voltage and current detection control circuit of high-voltage switch power supply
CN103472277A (en) * 2013-09-12 2013-12-25 昆山新金福精密电子有限公司 Voltmeter circuit
CN106706993A (en) * 2017-01-23 2017-05-24 惠州三华工业有限公司 Optocoupler current detection circuit
CN107462842A (en) * 2017-08-11 2017-12-12 黎明职业大学 A kind of direct current power source voltage current power isolation detection interface circuit
CN107656121A (en) * 2017-11-09 2018-02-02 珠海泰坦科技股份有限公司 A kind of low cost DC voltage isolation picking circuit
CN108152557A (en) * 2017-12-26 2018-06-12 常州三立精图光电有限公司 Sample circuit is isolated in a kind of feedback current
CN108318729A (en) * 2018-03-29 2018-07-24 福建工程学院 A kind of direct-current high voltage detection circuit
CN109031058A (en) * 2018-06-15 2018-12-18 华为技术有限公司 Insulation detection device and insulation detecting circuit
CN109254200A (en) * 2018-11-16 2019-01-22 美钻深海能源科技研发(上海)有限公司 For detecting the isolated DC voltage sensor of DC24V voltage stability
PL423693A1 (en) * 2017-12-04 2019-06-17 Instytut Tele-I Radiotechniczny System for measuring system with galvanic isolation
CN110045167A (en) * 2019-05-15 2019-07-23 浙江吉利控股集团有限公司 A kind of voltage and current detecting device
CN110412437A (en) * 2019-07-23 2019-11-05 欣旺达电子股份有限公司 Battery insulation detection circuit and battery insulation detection method
CN111060767A (en) * 2019-12-28 2020-04-24 广东盈科电子有限公司 ATE tester
CN112462258A (en) * 2020-11-06 2021-03-09 珠海格力电器股份有限公司 Motor terminal voltage detection method, device and circuit and air conditioning system
CN114034902A (en) * 2021-09-28 2022-02-11 海信(山东)空调有限公司 Phase voltage detection method and device, variable frequency air conditioner and control method and device thereof
CN114228498A (en) * 2021-11-10 2022-03-25 北京特种机械研究所 Electric automobile high voltage distribution busbar voltage measuring device

Cited By (25)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102104319A (en) * 2011-04-01 2011-06-22 欧瑞传动电气有限公司 IGBT drive circuit and control method
CN103023328B (en) * 2011-09-28 2016-01-20 中国科学院微电子研究所 Isolated voltage and current detection control circuit of high-voltage switch power supply
CN103023328A (en) * 2011-09-28 2013-04-03 中国科学院微电子研究所 Isolated voltage and current detection control circuit of high-voltage switch power supply
CN103023331B (en) * 2011-09-28 2015-09-30 中国科学院微电子研究所 Isolated voltage and current detection control circuit of high-voltage switch power supply
CN103023331A (en) * 2011-09-28 2013-04-03 中国科学院微电子研究所 Isolated voltage and current detection control circuit of high-voltage switch power supply
CN102967748A (en) * 2012-11-12 2013-03-13 宁波韵升股份有限公司 DC bus voltage detection circuit with high antijamming capability
CN103472277A (en) * 2013-09-12 2013-12-25 昆山新金福精密电子有限公司 Voltmeter circuit
CN106706993B (en) * 2017-01-23 2023-06-13 惠州三华工业有限公司 Optocoupler current detection circuit
CN106706993A (en) * 2017-01-23 2017-05-24 惠州三华工业有限公司 Optocoupler current detection circuit
CN107462842A (en) * 2017-08-11 2017-12-12 黎明职业大学 A kind of direct current power source voltage current power isolation detection interface circuit
CN107656121A (en) * 2017-11-09 2018-02-02 珠海泰坦科技股份有限公司 A kind of low cost DC voltage isolation picking circuit
PL234634B1 (en) * 2017-12-04 2020-03-31 Inst Tele I Radiotech System for measuring system with galvanic isolation
PL423693A1 (en) * 2017-12-04 2019-06-17 Instytut Tele-I Radiotechniczny System for measuring system with galvanic isolation
CN108152557A (en) * 2017-12-26 2018-06-12 常州三立精图光电有限公司 Sample circuit is isolated in a kind of feedback current
CN108318729A (en) * 2018-03-29 2018-07-24 福建工程学院 A kind of direct-current high voltage detection circuit
CN109031058A (en) * 2018-06-15 2018-12-18 华为技术有限公司 Insulation detection device and insulation detecting circuit
CN109254200A (en) * 2018-11-16 2019-01-22 美钻深海能源科技研发(上海)有限公司 For detecting the isolated DC voltage sensor of DC24V voltage stability
CN110045167A (en) * 2019-05-15 2019-07-23 浙江吉利控股集团有限公司 A kind of voltage and current detecting device
CN110412437A (en) * 2019-07-23 2019-11-05 欣旺达电子股份有限公司 Battery insulation detection circuit and battery insulation detection method
CN110412437B (en) * 2019-07-23 2021-05-11 欣旺达电子股份有限公司 Battery insulation detection circuit and battery insulation detection method
CN111060767A (en) * 2019-12-28 2020-04-24 广东盈科电子有限公司 ATE tester
CN112462258A (en) * 2020-11-06 2021-03-09 珠海格力电器股份有限公司 Motor terminal voltage detection method, device and circuit and air conditioning system
CN114034902A (en) * 2021-09-28 2022-02-11 海信(山东)空调有限公司 Phase voltage detection method and device, variable frequency air conditioner and control method and device thereof
CN114228498A (en) * 2021-11-10 2022-03-25 北京特种机械研究所 Electric automobile high voltage distribution busbar voltage measuring device
CN114228498B (en) * 2021-11-10 2024-03-22 北京特种机械研究所 High-voltage distribution bus voltage measuring device of electric automobile

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