CN219434936U - Residual voltage detection module circuit based on resistance-capacitance voltage reduction - Google Patents
Residual voltage detection module circuit based on resistance-capacitance voltage reduction Download PDFInfo
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- CN219434936U CN219434936U CN202223560775.3U CN202223560775U CN219434936U CN 219434936 U CN219434936 U CN 219434936U CN 202223560775 U CN202223560775 U CN 202223560775U CN 219434936 U CN219434936 U CN 219434936U
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B70/00—Technologies for an efficient end-user side electric power management and consumption
- Y02B70/10—Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes
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Abstract
The utility model discloses a residual voltage detection module circuit based on resistance-capacitance voltage reduction, which mainly comprises five parts, namely a resistance-capacitance voltage reduction circuit, a full-wave rectification voltage stabilizing circuit, a residual voltage detection circuit, a residual voltage signal isolation circuit and a power isolation circuit. The utility model has the advantages that the reliability requirement of the residual voltage circuit is very high, the capacitor charging delay is used for detecting the residual voltage, the stability of the action of the residual voltage circuit is ensured, and the circuit can be automatically locked after the residual voltage is detected, so that the reliability is high; the residual voltage circuit cannot influence the internal circuit, and the design totally uses the isolation circuit to ensure that the internal circuit is not influenced.
Description
Technical Field
The utility model relates to the technical field of residual voltage detection, in particular to a residual voltage detection module circuit based on resistance-capacitance voltage reduction.
Background
In the automatic fault recovery process of power distribution, the feeder terminal FTU or the station terminal DTU is required to detect the voltage of a breaker switch under the condition that the system is powered down, and the system is ensured not to malfunction in the power grid recovery process through the stored residual voltage state, so that the power supply reliability is improved, and the running safety of the power grid is ensured.
At present, a residual voltage blocking detection method is more used in a power supply loop. According to the method, a transformer is used for voltage transformation, after residual voltage is detected, a relay is enabled to obtain electricity to output residual voltage signals, meanwhile, a capacitor is charged, after the capacitor is charged to reach a certain voltage, a circuit of the relay is cut off, and the circuit is locked.
The transformer used in the scheme has high cost, and the voltage compatibility is not strong, so that the transformer cannot be compatible with 57.7V/100V/220V power supply. Without the DC voltage stabilizing circuit, the abrupt change of circuit voltage may burn the transformer and the subsequent circuit. No time delay detection exists, the circuit acts as long as the voltage is detected, and the reliability is not strong.
Disclosure of Invention
The utility model aims at overcoming the technical defects in the prior art and discloses a residual voltage detection module circuit based on resistance-capacitance voltage reduction.
In order to achieve the purpose of the utility model, the technical scheme adopted by the utility model is as follows:
the residual voltage detection module circuit based on resistance-capacitance voltage reduction comprises a resistance-capacitance voltage reduction circuit, wherein the resistance-capacitance voltage reduction circuit is electrically connected with a full-wave rectifying circuit, the full-wave rectifying circuit is electrically connected with a residual voltage detection circuit, and the residual voltage detection circuit is electrically connected with a residual voltage signal isolation circuit and a power supply isolation circuit; the residual voltage detection circuit comprises a double-coil relay, a first pin of the double-coil relay is electrically connected with a tenth pin of the double-coil relay and a cathode of a fourth diode, a fourth pin of the double-coil relay is grounded, a fifth pin of the double-coil relay is electrically connected with one end of a second capacitor, an anode of the second diode and a residual voltage signal isolation circuit, the other end of the second capacitor is electrically connected with a second diode, a first resistor and a residual voltage signal isolation circuit, the other end of the first resistor is electrically connected with a power isolation circuit, a seventh pin of the double-coil relay is electrically connected with an anode of the fifth diode and a residual voltage signal isolation circuit, a sixth pin of the double-coil relay is electrically connected with a cathode of the fifth diode and a cathode of the power isolation circuit, a twelfth pin of the double-coil relay is electrically connected with an anode of the fourth diode, a ninth pin of the double-coil relay is electrically connected with one end of a full-wave rectification circuit, one end of the twenty-seventh resistor, one end of a power supply end of a comparator and one end of a thirteenth resistor, one end of the thirteenth resistor is electrically connected with one end of the ninth capacitor and a positive input end of the comparator, one end of the reverse input end of the comparator is electrically connected with one end of the twenty-sixth resistor and the other end of the twenty-sixth resistor, one end of the other end of the twenty-sixth resistor and the other end of the twenty-sixth resistor is electrically connected with the twenty-sixth diode, the other end of the twenty-sixth resistor is electrically connected with the anode of the third diode and the cathode of the third diode, the anode of the third diode and the cathode of the third diode is connected with the cathode of the positive electrode, the third diode and the anode of the third diode and the cathode of the third diode is electrically, the emitter of the first triode is grounded, the collector of the first triode is electrically connected with the twelfth pin of the double-coil relay, and the other end of the fourth resistor is electrically connected with the other end of the seventh resistor and the full-wave rectifying circuit.
Further, the resistance-capacitance voltage reduction circuit comprises a piezoresistor, one end of the piezoresistor is electrically connected with one end of a third resistor, one end of a third capacitor and one end of a fifth resistor, the other end of the third resistor is electrically connected with the A-phase voltage, the other end of the third capacitor is electrically connected with the other end of the fifth resistor and the full-wave rectifying circuit, the other end of the piezoresistor is electrically connected with one end of a ninth resistor, one end of a twelfth resistor and the full-wave rectifying circuit, the other end of the ninth resistor is electrically connected with the N-phase voltage, and the other end of the twelfth resistor is electrically connected with the B-phase voltage.
Further, the full-wave rectifying circuit comprises a rectifier, a third pin and a fourth pin of the rectifier are electrically connected with the resistance-capacitance voltage reduction circuit, a second pin of the rectifier is grounded, a first pin of the rectifier is electrically connected with the anode of the fourth electrolytic capacitor, one end of the fifth capacitor, one end of the sixth resistor, one end of the adjustable voltage stabilizing source, a ninth pin of the double-coil relay, the other end of the fourth resistor and the other end of the seventh resistor, a negative electrode of the fourth electrolytic capacitor is electrically connected with the other end of the fifth capacitor, one end of the eighth resistor, the other end of the adjustable voltage stabilizing source, the other end of the sixth capacitor and a ground signal, and the other end of the sixth resistor is electrically connected with the other end of the eighth resistor and the adjustable voltage stabilizing source.
Further, the residual voltage signal isolation circuit includes a third optocoupler, a first pin of the third optocoupler is electrically connected to one end of the tenth resistor and one end of the eighth capacitor, the other end of the tenth resistor is electrically connected to the other end of the second resistor, a second pin of the third optocoupler is electrically connected to one end of the eleventh resistor and the other end of the eighth capacitor, the other end of the eleventh resistor is electrically connected to the other end of the second resistor, a third pin of the third optocoupler is electrically connected to one end of the seventh capacitor and a ground signal, a fourth pin of the third optocoupler is electrically connected to the other end of the seventh capacitor and a seventh pin of the dual-coil relay, the other end of the second resistor is electrically connected to one end of the first capacitor and the fourth pin of the fourth optocoupler, the first pin of the fourth optocoupler is electrically connected to the second diode cathode, one end of the second capacitor and the second diode anode, and the third pin of the fourth optocoupler is electrically connected to the other end of the first capacitor and the ground signal.
Further, the power isolation circuit comprises an isolation power module, a first pin of the isolation power module is electrically connected with the first input voltage, one end of an eighteenth capacitor and one end of a seventeenth capacitor, a second pin of the isolation power module is electrically connected with a ground signal, the other end of the eighteenth capacitor and the other end of the seventeenth capacitor, a fifth pin of the isolation power module is electrically connected with one end of a nineteenth capacitor, one end of a twentieth capacitor, a ground signal and a twenty-fifth resistor, and a seventh pin of the isolation power module is electrically connected with the other end of the nineteenth capacitor, the other end of the twentieth capacitor, a sixth pin of a double-coil relay and the other end of the twenty-fifth resistor.
Compared with the prior art, the utility model has the advantages that:
1. the residual voltage circuit needs to be adjusted according to a power supply mode used on site, and the design can switch the detected phase voltage or line voltage through resistors R9 and R12.
2. The residual voltage circuit needs to be miniaturized, and the design uses the resistance-capacitance step-down circuit to replace a transformer circuit, so that the requirement of 57.7V/100V/220V residual voltage detection can be met simultaneously.
3. The reliability requirement of the residual voltage circuit is very high, the capacitor charging delay is used for detecting the residual voltage, the stability of the action of the residual voltage circuit is guaranteed, and the circuit can be automatically locked after the residual voltage is detected, so that the reliability is high.
4. The residual voltage circuit cannot influence the internal circuit, and the design totally uses the isolation circuit to ensure that the internal circuit is not influenced.
Drawings
FIG. 1 is a circuit diagram of a resistance-capacitance step-down, full-wave rectification and residual voltage detection circuit of the utility model;
FIG. 2 is a circuit diagram of the residual voltage detection, residual voltage signal isolation and power isolation of the present utility model.
Detailed Description
The utility model is described in further detail below with reference to the drawings and the specific examples. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the utility model.
Example 1
The circuit can meet the requirement of measuring 57.7V/100V/220V circuits, the time for inputting an alternating current power supply is longer than 35ms, the relay can act and output a residual voltage signal to the internal controller, and the internal controller can send a reset signal to reset the residual voltage detection circuit.
The design mainly comprises five parts, namely a resistance-capacitance voltage reduction circuit, a full-wave rectification voltage stabilizing circuit, a residual voltage detection circuit, a residual voltage signal isolation circuit and a power isolation circuit.
The resistance-capacitance voltage-reducing circuit consists of resistors R3, R5, R9 and R12, a capacitor C3 and a piezoresistor RV 2. R9 and R19 are used for switching detection modes, R9 detects phase voltage, and R12 detects line voltage; RV1 is a piezoresistor, and a post-stage circuit is burnt out after the simulation input voltage is overlarge; c3 is a current-limiting capacitor, and the impedance of C3 in the circuit is X C =1/ωc, ω is the angular frequency of the ac power supply, maximum current I of the circuit MAX ＝U A /X C The voltage across the load and the capacitor can be dynamically distributed. The design adopts an X2 safety capacitor with the capacity of 1uF, so that the safety of the circuit is ensured; r3 is used for absorbing the surge and surge of the alternating current power supply, R5 provides a discharging path for the capacitor C3, and the capacitor can be safely discharged after power failure, so that personal safety is protected.
The full-wave rectifying and voltage stabilizing circuit consists of a rectifier REC1, an electrolytic capacitor C4, a capacitor C5, an adjustable voltage stabilizing source U2 and resistors R6 and R8. The circuit can convert alternating current signals into direct current signals and is used for power supply and residual voltage detection of a later-stage circuit. The rectifier bridge REC1 firstly converts the input alternating current into pulsating direct current, then a capacitor filter circuit formed by C4 and C5 is changed into smoother direct current, and finally a TL431 voltage stabilizing circuit formed by U2, R6 and R8 stabilizes the output voltage at
The residual voltage detection circuit consists of resistors R4, R7, R13 and R26, capacitors C6, C7 and C9, common diodes D1, D3, D4 and D5, voltage stabilizing diodes Z1 and Z2, triodes V1 and V2 and a double-coil relay K1. The circuit has the functions of detecting residual voltage in a delayed manner, automatically locking and the like. At the moment of power-on, HVCC charges capacitor C9 through resistor R13, U7 has the same phase input terminal voltage Inverting input terminal voltage +.> At this time, the voltage at the non-inverting input terminal of the comparator U7 is smaller than the voltage at the inverting input terminal, the output of the comparator U7 is low level (0V), the diodes D1 and D3 are turned on, the zener diodes Z1 and Z2 are in the inverted cut-off state, the triodes V1 and V2 are turned off, the C6 discharges through D3, the coil 1 of the relay K1 is not powered on, and no residual voltage signal is output.
After a period of time, when the voltage at two ends of the capacitor C9 rises to be greater than the voltage at two ends of the R26, the voltage at the non-inverting input end of the comparator U7 is greater than the voltage at the inverting input end, the output of the comparator U7 is high level (HVCC voltage), the D1 and the D2 are cut off, the voltage stabilizing tube Z1 breaks down reversely, so that the V1 is saturated, the HVCC charges the capacitor C6 through the resistor R7, the voltage stabilizing tube Z2 is cut off, and the triode V2 is cut off. PW3 is connected with HVCC through the auxiliary contact of relay K1, and COM2 is grounded owing to the conduction of triode V1, and coil 1 of K1 gets the electricity, makes 3, 4 feet disconnection, 9, 10 feet disconnection of relay, 4, 5 feet links to each other, 8, 9 feet links to each other. PW3 is disconnected from the HVCC direct auxiliary contact, and coil 1 of K1 is deenergized. The circuit outputs a residual voltage signal.
After the voltage at two ends of C6 rises to reversely breakdown the voltage stabilizing tube Z2, the triode V2 is saturated, the PW2 voltage is connected to the ground to cut off the voltage stabilizing tube Z1, the triode V1 is cut off, the COM2 is suspended, and the residual voltage circuit is locked. R4 is used as a dummy load to protect the normal operation of the resistance-capacitance voltage-reducing circuit.
The residual voltage signal isolation circuit consists of capacitors C7, C10 and C11, resistors R10, R11, R14 and R15, a diode D7 and optocouplers U3 and U4. The circuit isolates the residual voltage detection circuit from internal working current and protects equipment from external interference. After the residual voltage detection circuit detects residual voltage, the optocoupler U4 is conducted, and low level is output to the internal controller. The internal controller can output a low level to send out a residual voltage reset signal, the optocoupler U3 is conducted, FG is connected to the ground, and the coil 2 of the relay K1 is powered on to reset the relay. The first pin of U4 is connected with R1 resistance, and when K1 relay acts, the 5 th pin and the 4 th pin of K1 are connected. The first and second legs of U4 form a loop, and the third and fourth legs of U4 conduct to pull the R2 resistor low. At this time, a low level is output to the internal controller.
The power isolation circuit consists of capacitors C17, C18, C19, C20, a resistor R25 and an isolated power module U6. The circuit can become the 12V voltage that can drive the relay with inside 5V voltage, uses isolation power module, and protection inside 5V power is not disturbed by the outside, and R25 can provide the load, guarantees power module normal operating.
The foregoing is merely a preferred embodiment of the present utility model and it should be noted that modifications and adaptations to those skilled in the art may be made without departing from the principles of the present utility model, which are intended to be comprehended within the scope of the present utility model.
Claims (5)
1. Residual voltage detection module circuit based on resistance-capacitance step-down, including resistance-capacitance step-down circuit, its characterized in that: the resistance-capacitance voltage reduction circuit is electrically connected with the full-wave rectification circuit, the full-wave rectification circuit is electrically connected with the residual voltage detection circuit, and the residual voltage detection circuit is electrically connected with the residual voltage signal isolation circuit and the power supply isolation circuit; the residual voltage detection circuit comprises a double-coil relay (K1), a first pin of the double-coil relay (K1) is electrically connected with a tenth pin of the double-coil relay (K1) and a cathode of a fourth diode (D4), a fourth pin of the double-coil relay (K1) is grounded, a fifth pin of the double-coil relay (K1) is electrically connected with one end of a second capacitor (C2), an anode of the second diode (D2) and a residual voltage signal isolation circuit, the other end of the second capacitor (C2) is electrically connected with the second diode (D2), a first resistor (R1) and the residual voltage signal isolation circuit, the other end of the first resistor (R1) is electrically connected with the power isolation circuit, a seventh pin of the double-coil relay (K1) is electrically connected with an anode of a fifth diode (D5) and the power isolation circuit, a twelfth pin of the double-coil relay (K1) is electrically connected with an anode of the fourth diode (D4), a thirteenth pin of the double-coil relay (K1) is electrically connected with a cathode of the fifth diode (D5) and the power isolation circuit, a thirteenth pin of the double-coil relay (K1) is electrically connected with one end of the thirteenth resistor (D7) and one end of the thirteenth resistor (C13) of the positive resistor (R7) is connected with one end of the positive resistor (R7), the reverse input end of the comparator (U7) is electrically connected with one end of a twenty-sixth resistor (R26) and the other end of a twenty-seventh resistor (R27), the other end of the twenty-sixth resistor (R26) is electrically connected with one end of a sixth capacitor (C6), a ground signal and a full-wave rectifying circuit, the output end of the comparator (U7) is electrically connected with the cathode of a third diode (D3) and the cathode of a first diode (D1), the anode of the third diode (D3) is electrically connected with the cathode of a second zener diode (Z2), one end of the seventh resistor (R7) and the other end of the sixth capacitor (C6), the anode of the second zener diode (Z2) is electrically connected with the base of a second triode (V2), the emitter of the second triode (V2) is grounded, the collector of the second triode (V2) is electrically connected with one end of a fourth resistor (R4), the anode of the first diode (D1) and the cathode of the first zener diode (Z1), the anode of the first zener diode (Z1) is electrically connected with the anode of the third diode (D1), the other end of the third triode (V1) is electrically connected with the base of the fourth resistor (R1), and the other end of the third triode (R1) is electrically connected with the full-wave rectifying circuit.
2. The residual voltage detection module circuit based on resistive-capacitive voltage reduction as claimed in claim 1, wherein: the resistance-capacitance voltage reduction circuit comprises a piezoresistor (RV 1), one end of the piezoresistor (RV 1) is electrically connected with one end of a third resistor (R3), one end of a third capacitor (C3) and one end of a fifth resistor (R5), the other end of the third resistor (R3) is electrically connected with an A-phase voltage (UA), the other end of the third capacitor (C3) is electrically connected with the other end of the fifth resistor (R5) and a full-wave rectifying circuit, the other end of the piezoresistor (RV 1) is electrically connected with one end of a ninth resistor (R9), one end of a twelfth resistor (R12) and the full-wave rectifying circuit, the other end of the ninth resistor (R9) is electrically connected with an N-phase voltage (UN), and the other end of the twelfth resistor (R12) is electrically connected with a B-phase voltage (UB).
3. The residual voltage detection module circuit based on resistive-capacitive voltage reduction as claimed in claim 1, wherein: the full-wave rectification circuit comprises a rectifier (REC 1), a third pin and a fourth pin of the rectifier (REC 1) are electrically connected with a resistance-capacitance voltage reduction circuit, a second pin of the rectifier (REC 1) is grounded, a first pin of the rectifier (REC 1) is electrically connected with the positive electrode of a fourth electrolytic capacitor (C4), one end of a fifth capacitor (C5), one end of a sixth resistor (R6), one end of an adjustable voltage stabilizing source (U2) and the ninth pin of a double-coil relay (K1), the other end of a fourth resistor (R4) and the other end of a seventh resistor (R7), the negative electrode of the fourth electrolytic capacitor (C4) is electrically connected with the other end of the fifth capacitor (C5), one end of an eighth resistor (R8), the other end of the adjustable voltage stabilizing source (U2), the other end of the sixth capacitor (C6) and a ground signal, and the other end of the sixth resistor (R6) is electrically connected with the other end of the eighth resistor (R8) and the adjustable voltage stabilizing source (U2).
4. The residual voltage detection module circuit based on resistive-capacitive voltage reduction as claimed in claim 1, wherein: the residual voltage signal isolation circuit comprises a third optocoupler (U3) and a fourth optocoupler (U4), wherein a first pin of the third optocoupler (U3) is electrically connected with one end of a tenth resistor (R10) and one end of an eighth capacitor (C8), the other end of the tenth resistor (R10) is electrically connected with one end of a second resistor (R2), a second pin of the third optocoupler (U3) is electrically connected with one end of an eleventh resistor (R11) and the other end of an eighth capacitor (C8), the other end of the eleventh resistor (R11) is electrically connected with one end of a second resistor (R2), a third pin of the third optocoupler (U3) is electrically connected with one end of a seventh capacitor (C7) and a ground signal, a fourth pin of the third optocoupler (U3) is electrically connected with the other end of the seventh capacitor (C7) and a seventh pin of a double-coil relay (K1), one end of the second resistor (R2) is electrically connected with one end of the fourth resistor (U4) and the other end of the fourth resistor (U4), and the other end of the fourth resistor (U2) is electrically connected with the fourth pin of the fourth resistor (U2) and the fourth resistor (C1).
5. The residual voltage detection module circuit based on resistive-capacitive voltage reduction as claimed in claim 1, wherein: the power isolation circuit comprises an isolation power module (U6), a first pin of the isolation power module (U6) is electrically connected with a first input voltage (V5P 0), one end of an eighteenth capacitor (C18) and one end of a seventeenth capacitor (C17), a second pin of the isolation power module (U6) is electrically connected with a ground signal, the other end of the eighteenth capacitor (C18) and the other end of the seventeenth capacitor (C17), a fifth pin of the isolation power module (U6) is electrically connected with one end of a nineteenth capacitor (C19), one end of a twentieth capacitor (C20), a ground signal and a twenty-fifth resistor (R25), and a seventh pin of the isolation power module (U6) is electrically connected with the other end of the nineteenth capacitor (C19), the other end of the twentieth capacitor (C20), a sixth pin of a double-coil relay (K1) and the other end of the twenty-fifth resistor (R25).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202223560775.3U CN219434936U (en) | 2022-12-30 | 2022-12-30 | Residual voltage detection module circuit based on resistance-capacitance voltage reduction |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202223560775.3U CN219434936U (en) | 2022-12-30 | 2022-12-30 | Residual voltage detection module circuit based on resistance-capacitance voltage reduction |
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| Publication Number | Publication Date |
|---|---|
| CN219434936U true CN219434936U (en) | 2023-07-28 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202223560775.3U Active CN219434936U (en) | 2022-12-30 | 2022-12-30 | Residual voltage detection module circuit based on resistance-capacitance voltage reduction |
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| CN (1) | CN219434936U (en) |
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2022
- 2022-12-30 CN CN202223560775.3U patent/CN219434936U/en active Active
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