CN111707967A - Alternating current leakage voltage detection device - Google Patents
Alternating current leakage voltage detection device Download PDFInfo
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- CN111707967A CN111707967A CN202010462426.4A CN202010462426A CN111707967A CN 111707967 A CN111707967 A CN 111707967A CN 202010462426 A CN202010462426 A CN 202010462426A CN 111707967 A CN111707967 A CN 111707967A
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- resistor
- drain voltage
- protection point
- circuit
- alternating current
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- 238000001514 detection method Methods 0.000 title claims abstract description 19
- 230000007246 mechanism Effects 0.000 claims abstract description 25
- 238000001914 filtration Methods 0.000 claims abstract description 13
- 239000003990 capacitor Substances 0.000 claims description 19
- 230000003287 optical effect Effects 0.000 claims description 8
- 238000000034 method Methods 0.000 description 5
- 238000005070 sampling Methods 0.000 description 5
- 230000008569 process Effects 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 230000009471 action Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 230000004044 response Effects 0.000 description 1
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/50—Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections
- G01R31/52—Testing for short-circuits, leakage current or ground faults
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- 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
- H02H3/26—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 difference between voltages or between currents; responsive to phase angle between voltages or between currents
- H02H3/32—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 difference between voltages or between currents; responsive to phase angle between voltages or between currents involving comparison of the voltage or current values at corresponding points in different conductors of a single system, e.g. of currents in go and return conductors
- H02H3/325—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 difference between voltages or between currents; responsive to phase angle between voltages or between currents involving comparison of the voltage or current values at corresponding points in different conductors of a single system, e.g. of currents in go and return conductors involving voltage comparison
Abstract
The invention discloses an alternating current drain voltage detection device which is characterized by comprising a drain voltage input end, a rectification filter circuit, a drain voltage protection point comparison circuit, a drain voltage protection point calibration circuit, a control mechanism and a switch signal output end, wherein the switch signal output end is connected with the output end of the control mechanism; the input end of the rectification filter circuit is communicated with the drain voltage input end, the input end of the drain voltage protection point comparison circuit is connected with the output end of the rectification filter circuit, and the output end of the drain voltage protection point comparison circuit is communicated with the control mechanism; the leakage voltage protection point setting circuit gives an overvoltage point of leakage voltage through a voltage reference given by the rectifying and filtering circuit and a voltage dividing circuit of the leakage voltage setting circuit; the control mechanism can control the on-off of the alternating current input through the single chip microcomputer according to the high-low level state of the preceding-stage voltage when the alternating current leakage voltage input meets the protection control requirement, and therefore alternating current leakage voltage protection is achieved.
Description
Technical Field
The invention relates to a leakage voltage detection device, in particular to an alternating current leakage voltage detection device.
Background
In the technical field of electromechanical control, the design of alternating current drain voltage protection is one of important problems to be considered when designing products. With the diversification of power supply sources and the increase of the demand of electric equipment, the electromechanical control system puts higher requirements on the detection of the drain voltage. The existing leakage voltage device on the current market mainly has two realization processes, firstly, no leakage voltage detection exists in a product device, and the leakage voltage is detected through external auxiliary equipment such as a voltmeter; and secondly, a restorable thermistor is connected between the zero line and the ground, when the current passing through the thermistor is increased, the thermistor is heated to reach the parameter value of the thermistor, and the input power supply is cut off through a mechanical execution structure.
The protection devices aimed at by the two alternating current drain voltage protection devices are complex in structure, or the protection devices cannot be integrated in a product circuit and are low in safety coefficient, or low in precision and slow in response, and the capacity of both the protection devices is not provided; the method has the advantages that the drain voltage value of a product needs to be artificially detected by adopting a universal meter for detecting the drain voltage, and then manual control protection is carried out, so that the operation process is complex, and the function of safety protection cannot be effectively realized; the leakage voltage protection strategy of the linkage adjusting mechanism is adopted, the action of the mechanical actuating mechanism is driven when the thermosensitive voltage is cut off, the precision is not high, the cost is high, the size is large, the requirement of miniaturization of the existing product cannot be met, and the linkage adjusting mechanism cannot be used in the occasions of the existing intelligent control market.
Disclosure of Invention
The present invention is directed to an ac leakage voltage detecting apparatus to solve the above problems.
In order to achieve the purpose, the invention provides the following technical scheme:
an alternating current drain voltage detection device comprises a drain voltage input end, a rectification filter circuit, a drain voltage protection point comparison circuit, a drain voltage protection point calibration circuit, a control mechanism and a switch signal output end;
the input end of the rectification filter circuit is communicated with the drain voltage input end and is used for rectifying and filtering an alternating current leakage power supply to form direct current, the input end of the drain voltage protection point comparison circuit is connected with the output end of the rectification filter circuit, the output end of the drain voltage protection point comparison circuit is communicated with the control mechanism, the drain voltage is compared by the drain voltage protection point comparison circuit and a comparison result is output to the control mechanism, and the drain voltage protection point calibration circuit is connected with the drain voltage protection point comparison circuit and is used for calibrating the precision of the drain voltage protection point comparison circuit.
As a further scheme of the invention: the rectifying and filtering circuit comprises a first diode, a first resistor, a second capacitor and a fourth diode which are sequentially connected in series, wherein the first diode is communicated with the drain voltage input end, and the fourth diode is connected with the grounding end.
As a further scheme of the invention: the rear end of the rectifying and filtering circuit is connected with an electric leakage protection point circuit, the electric leakage protection point circuit comprises a second resistor and a fifth resistor which are connected in series, the second resistor and the fifth resistor are connected in parallel with a second capacitor, a leakage voltage protection point is arranged between the second resistor and the fifth resistor, and the voltage of the leakage voltage protection point is U1.
As a further scheme of the invention: the leakage voltage protection point calibration circuit comprises a sixth resistor, an eighth resistor, a seventh resistor and a third capacitor, wherein the seventh resistor is an adjustable resistor, the sixth resistor is connected with the leakage protection point, and the eighth resistor is connected with a power input end.
As a further scheme of the invention: the drain voltage protection point comparison circuit comprises a comparison circuit integrator and a first capacitor, wherein the comparison circuit integrator is communicated with the sixth resistor, the seventh resistor, the third capacitor and the control mechanism.
As a further scheme of the invention: the control mechanism comprises a third resistor, a fourth resistor and an optocoupler, wherein a light emitting diode and a photoresistor are arranged in the optocoupler, two ends of the light emitting diode are respectively connected with the fourth resistor and the drain voltage protection point comparison circuit, two ends of the photoresistor are respectively communicated with the third resistor and a grounding end, and the other end of the third resistor is connected with a voltage input end.
As a further scheme of the invention: and the switch signal output end is connected between the third resistor and the optocoupler.
As a further scheme of the invention: and two ends of the second capacitor are connected with a third diode in parallel, two ends of the fifth resistor are connected with a second diode in parallel, and the second diode and the third diode are protection diodes.
Compared with the prior art, the invention has the beneficial effects that:
1. the method and the device realize the setting, protection and calibration of the leakage voltage protection value under the alternating current input state, and realize the alternating current leakage voltage protection. The alternating current drain voltage protection device mainly comprises a rectification filter circuit, a drain voltage protection point setting circuit, a drain voltage precision calibration circuit and a control mechanism. The rectification filter circuit converts alternating current input into direct current and provides voltage reference for post-stage circuits such as a leakage voltage protection point setting circuit and the like; the leakage voltage protection point setting circuit provides an overvoltage point of leakage voltage through a voltage reference provided by the rectifying and filtering circuit and a voltage dividing circuit of the leakage voltage setting circuit; the control mechanism can control the on-off of the alternating current input through the single chip microcomputer according to the high-low level state of the preceding-stage voltage when the alternating current leakage voltage input meets the protection control requirement, and therefore alternating current leakage voltage protection is achieved.
2. According to the voltage reference protection control device, an alternating current input mode is converted into direct current through the rectifying and filtering circuit, a voltage reference is provided for a post-stage protection point setting circuit, the diversified requirements of the leakage voltage safety protection points are met, and the universality of the leakage voltage protection control device is improved; the single-chip microcomputer is used for sampling the potential value of the leakage voltage protection, the on-off of the alternating current input is controlled by the single-chip microcomputer instead of a linkage adjusting mechanism, the complexity and the cost are reduced, and the intelligent degree of the product is improved.
Drawings
FIG. 1 is a schematic block diagram of the present embodiment;
fig. 2 is a circuit diagram of the present embodiment.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Referring to fig. 1-2, in an embodiment of the present invention, an ac drain voltage detection apparatus includes an ac drain voltage detection apparatus, which includes a drain voltage input terminal, a rectifying filter circuit, a drain voltage protection point comparison circuit, a drain voltage protection point calibration circuit, a control mechanism, and a switch signal output terminal.
The input end of the rectification filter circuit is communicated with the drain voltage input end and is used for rectifying and filtering an alternating current leakage power supply to form direct current, the rectification filter circuit comprises a first diode 11, a first resistor 3, a second capacitor 16 and a fourth diode 14 which are sequentially connected in series, the first diode is communicated with the drain voltage input end, and the fourth diode 14 is connected with the grounding end.
The rear end of the rectifying and filtering circuit is connected with a leakage protection point circuit, the input end of the leakage voltage protection point comparison circuit is connected with the output end of the rectifying and filtering circuit, the leakage protection point circuit comprises a second resistor 4 and a fifth resistor 7 which are connected in series, the second resistor 4 and the fifth resistor 7 are connected with a second capacitor 16 in parallel, a leakage voltage protection point is arranged between the second resistor 4 and the fifth resistor 7, and the voltage of the leakage voltage protection point is U1.
The output end of the leakage voltage protection point comparison circuit is communicated with the control mechanism, the leakage voltage protection point comparison circuit comprises a comparison circuit integrator 18 and a first capacitor 15, the comparison circuit integrator 18 adopts LM293, the comparison circuit integrator 18 is provided with three pins, the first pin, the second pin and the third pin, the second pin of the comparison circuit integrator 18 is communicated with a sixth resistor 8, the third pin of the comparison circuit integrator 18 is communicated with a seventh resistor 9 and a third capacitor 17, the first pin of the comparison circuit integrator 18 is communicated with the control mechanism, and when the voltage of 2 pins of the comparison circuit integrator is higher than the voltage of 3 pins, the voltage of 1 pin is 0V.
The leakage voltage protection point calibration circuit comprises a sixth resistor 8, an eighth resistor 10, a seventh resistor 9 and a third capacitor 17, wherein the seventh resistor 9 is an adjustable resistor, the sixth resistor 8 is connected with a leakage protection point, the eighth resistor 10 is connected with a power supply input end, the leakage voltage is compared by the leakage voltage protection point comparison circuit and a comparison result is output to the control mechanism, and the leakage voltage protection point calibration circuit is connected with the leakage voltage protection point comparison circuit and used for calibrating the precision of the leakage voltage protection point comparison circuit.
The control mechanism comprises a third resistor 5, a fourth resistor 6 and an optical coupler 19, wherein the optical coupler 19 adopts TP291, a light emitting diode and a photoresistor are arranged in the optical coupler 19, the two ends of the light emitting diode are respectively a pin 1 and a pin 2, the two ends of the photoresistor are respectively a pin 3 and a pin 4, the pin 3 is a cathode, the pin 4 is an anode, when the reference voltage (voltage of 1 to 2 pins) reaches 0.7V, the cathode (pin 3) is conducted to the anode (pin 4), the two ends of the light emitting diode are respectively connected with the fourth resistor 6 and a leakage voltage protection point comparison circuit, the two ends of the photoresistor are respectively communicated with the third resistor 5 and a grounding terminal, when the pin 1 and the pin 2 are conducted, the light emitting diode emits light, the resistance value of the photoresistor is reduced, the pin 3 is conducted to the pin 4, the pin is grounded, a switching signal output terminal 2 communicated with the pin 3 is grounded, a low level is output, the switch signal output end 2 is connected between the third resistor 5 and the optocoupler 19, and the switch signal output end 2 is connected with a single chip microcomputer and used for receiving detection information.
In addition, a second diode 12 and a third diode 13 are further provided, two ends of the second diode 12 are respectively connected with two ends of the fifth resistor 7, two ends of the third diode 13 are respectively connected with two ends of the second capacitor 16, and here, the second diode 12 and the third diode 13 are protection diodes for preventing the safety of the rear-stage circuit when the input voltage is too high.
When the invention is used, referring to fig. 1 and 2, the alternating current drain voltage is sent to the rectifying and filtering circuit through the INPUT port INPUT and the shell, and is converted into direct current after being rectified and filtered by the rectifying bridge diode D1, the diode D4, the resistor R1 and the capacitor C2, wherein D2 and D3 are clamping diodes, thereby protecting a post-stage circuit from being damaged due to overhigh INPUT voltage. When the alternating current drain voltage is gradually increased from 0, the voltage of the drain voltage protection point to the GND point is gradually increased, namely the voltage at U1 is increased, and when the value of the alternating current drain voltage reaches the drain voltage point voltage set by the drain voltage protection point, namely the voltage of the pin 2 of the comparison circuit integrator T2A is greater than the voltage of the pin 3, the voltage of the pin 1 of the comparison circuit integrator T2A is at a low level; at this moment, the voltage between the pin 1 and the pin 2 of the optical coupler 19 is greater than 0.7V, and the light emitting diode in the optical coupler 19 is switched on, so that the light dependent resistor is reduced, the pins 3 and 4 of the optical coupler 19 are switched on, namely, the OUTput end is switched on with the grounding end, and the voltage value of the OUTput pin is low level. And if the potential acquired by the singlechip is 0, reporting leakage voltage protection by the singlechip. In an actual circuit, because the resistance value has an accuracy problem, when an external drain voltage value is AC36V, the adjustable resistor R7 is adjusted to enable the single chip microcomputer to acquire a potential of 0, and the resistance value of the adjustable resistor R7 is fixed, so that calibration of drain voltage sampling accuracy and adjustment of a drain voltage protection point can be realized, and high-accuracy sampling accuracy is realized.
In the calibration process, the resistance value of the adjustable resistor R7 actually connected to the circuit is R7 ', and the voltage at the U2 can be adjusted by adjusting the magnitude of R7', as shown in formula 1. When the drain voltage input value is UD, the calculation formula of the drain voltage protection point voltage U1 is shown in formula 2:
when the alternating current drain voltage is input:
the external drain voltage is AC36V, then the resistance value of the adjustable resistor R7 actually connected to the circuit is adjusted to be R7', the voltage of a U1 point is larger than the voltage value of a U2 point, a port1 pin is at a low level, U1 is conducted, OUTPUT is at a low level, then the resistance value of the adjustable resistor R7 is fixed, calibration of drain voltage sampling accuracy and adjustment of a drain voltage protection point can be achieved, and high-accuracy sampling accuracy is achieved.
It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.
Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.
Claims (8)
1. An alternating current drain voltage detection device is characterized by comprising a drain voltage input end, a rectification filter circuit, a drain voltage protection point comparison circuit, a drain voltage protection point calibration circuit, a control mechanism and a switch signal output end;
the input end of the rectification filter circuit is communicated with the drain voltage input end and is used for rectifying and filtering an alternating current leakage power supply to form direct current, the input end of the drain voltage protection point comparison circuit is connected with the output end of the rectification filter circuit, the output end of the drain voltage protection point comparison circuit is communicated with the control mechanism, the drain voltage is compared by the drain voltage protection point comparison circuit and a comparison result is output to the control mechanism, and the drain voltage protection point calibration circuit is connected with the drain voltage protection point comparison circuit and is used for calibrating the precision of the drain voltage protection point comparison circuit.
2. An alternating current drain voltage detection device according to claim 1, wherein the rectifying and filtering circuit comprises a first diode (11), a first resistor (3), a second capacitor (16) and a fourth diode (14) which are connected in series in sequence, the first diode is communicated with the drain voltage input end, and the fourth diode (14) is connected with the ground end.
3. An alternating current leakage voltage detection device according to claim 2, wherein a leakage protection point circuit is connected to a rear end of the rectifying and filtering circuit, the leakage protection point circuit includes a second resistor (4) and a fifth resistor (7) connected in series, the second resistor (4) and the fifth resistor (7) are connected in parallel with a second capacitor (16), a leakage voltage protection point is arranged between the second resistor (4) and the fifth resistor (7), and a voltage of the leakage voltage protection point is U1.
4. An alternating current leakage voltage detection device according to claim 3, characterized in that the leakage voltage protection point calibration circuit comprises a sixth resistor (8), an eighth resistor (10), a seventh resistor (9) and a third capacitor (17), wherein the seventh resistor (9) is an adjustable resistor, the sixth resistor (8) is connected with the leakage protection point, and the eighth resistor (10) is connected with the power input terminal.
5. An alternating current drain voltage detection device according to claim 4, characterized in that the drain voltage protection point comparison circuit comprises a comparison circuit integrator (18) and a first capacitor (15), wherein the comparison circuit integrator (18) is communicated with the sixth resistor (8), the seventh resistor (9), the third capacitor (17) and a control mechanism.
6. The alternating current leakage voltage detection device according to claim 1, wherein the control mechanism comprises a third resistor (5), a fourth resistor (6) and an optical coupler (19), a light emitting diode and a photoresistor are arranged in the optical coupler (19), two ends of the light emitting diode are respectively connected with the fourth resistor (6) and the leakage voltage protection point comparison circuit, two ends of the photoresistor are respectively communicated with the third resistor (5) and a ground terminal, and the other end of the third resistor (5) is connected with a voltage input end.
7. An alternating current drain voltage detection device according to claim 1, characterized in that said switching signal output terminal (2) is connected between a third resistor (5) and an opto-coupler (19).
8. An alternating current drain voltage detection device according to claim 3, wherein a third diode (13) is connected in parallel with two ends of the second capacitor (16), a second diode (12) is connected in parallel with two ends of the fifth resistor (7), and the second diode (12) and the third diode (13) are protection diodes.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010462426.4A CN111707967A (en) | 2020-05-27 | 2020-05-27 | Alternating current leakage voltage detection device |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202010462426.4A CN111707967A (en) | 2020-05-27 | 2020-05-27 | Alternating current leakage voltage detection device |
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| CN111707967A true CN111707967A (en) | 2020-09-25 |
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| CN202010462426.4A Pending CN111707967A (en) | 2020-05-27 | 2020-05-27 | Alternating current leakage voltage detection device |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112379174A (en) * | 2020-11-30 | 2021-02-19 | 贵州航天风华实业有限公司 | Circuit for detecting resistance and drain voltage of same-line |
| CN114233845A (en) * | 2021-11-12 | 2022-03-25 | 中国北方车辆研究所 | Wheeled chariot prevents putting into gear AT derailleur control system of two |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201219194Y (en) * | 2008-06-18 | 2009-04-08 | 合肥同智科技发展有限公司 | AC creepage protection circuit |
| CN108173243A (en) * | 2018-01-18 | 2018-06-15 | 苏州超云新能源有限公司 | inverter leakage protection circuit and inverter |
-
2020
- 2020-05-27 CN CN202010462426.4A patent/CN111707967A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201219194Y (en) * | 2008-06-18 | 2009-04-08 | 合肥同智科技发展有限公司 | AC creepage protection circuit |
| CN108173243A (en) * | 2018-01-18 | 2018-06-15 | 苏州超云新能源有限公司 | inverter leakage protection circuit and inverter |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112379174A (en) * | 2020-11-30 | 2021-02-19 | 贵州航天风华实业有限公司 | Circuit for detecting resistance and drain voltage of same-line |
| CN114233845A (en) * | 2021-11-12 | 2022-03-25 | 中国北方车辆研究所 | Wheeled chariot prevents putting into gear AT derailleur control system of two |
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Application publication date: 20200925 |
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