CN110086162B - Direct-current power supply anti-reverse connection circuit with self-checking interlocking anti-interference function - Google Patents
Direct-current power supply anti-reverse connection circuit with self-checking interlocking anti-interference function Download PDFInfo
- Publication number
- CN110086162B CN110086162B CN201910521988.9A CN201910521988A CN110086162B CN 110086162 B CN110086162 B CN 110086162B CN 201910521988 A CN201910521988 A CN 201910521988A CN 110086162 B CN110086162 B CN 110086162B
- Authority
- CN
- China
- Prior art keywords
- voltage
- resistor
- power supply
- unit
- voltage division
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 230000002265 prevention Effects 0.000 claims abstract description 16
- 239000003990 capacitor Substances 0.000 claims description 33
- 230000005669 field effect Effects 0.000 claims description 15
- 238000002955 isolation Methods 0.000 claims description 15
- 230000000087 stabilizing effect Effects 0.000 claims description 6
- 238000010586 diagram Methods 0.000 description 8
- 238000000034 method Methods 0.000 description 8
- 238000006243 chemical reaction Methods 0.000 description 4
- 230000008569 process Effects 0.000 description 4
- 230000009471 action Effects 0.000 description 3
- 238000001914 filtration Methods 0.000 description 3
- 238000004378 air conditioning Methods 0.000 description 2
- 230000008901 benefit Effects 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 238000011160 research Methods 0.000 description 2
- 230000002159 abnormal effect Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 230000007257 malfunction Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 230000006641 stabilisation Effects 0.000 description 1
- 238000011105 stabilization Methods 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H11/00—Emergency protective circuit arrangements for preventing the switching-on in case an undesired electric working condition might result
- H02H11/002—Emergency protective circuit arrangements for preventing the switching-on in case an undesired electric working condition might result in case of inverted polarity or connection; with switching for obtaining correct connection
Landscapes
- Power Conversion In General (AREA)
Abstract
The invention provides a direct-current power supply reverse connection prevention circuit with a self-checking interlocking anti-interference function. When a direct-current power supply is reversely connected, the two ends of the first voltage division unit and the second voltage division unit are not provided with electric potential differences, the first voltage division end and the second voltage division end are not provided with voltage signals, the controllable switch unit cannot be conducted, a positive input signal loaded on a direct-current output end cannot be connected into a circuit loop, and a load connected into the circuit cannot work; when the direct-current power supply is connected positively, as long as the voltage signal of the first voltage division end obtained by voltage division from the direct-current input end and the voltage signal of the second voltage division end obtained by voltage division from the output end of the switching power supply are obtained, any one of the two voltage signals can reach the starting voltage of the controllable switching unit, and then the controllable switching unit can be switched on. According to the invention, the problem of low reliability of the direct-current power supply reverse connection prevention circuit based on the controllable switch unit due to voltage fluctuation is solved, and the reliability of the direct-current power supply reverse connection prevention circuit is improved.
Description
Technical Field
The invention relates to the field of power supplies, in particular to a direct-current power supply anti-reverse connection circuit with a self-checking interlocking anti-interference function.
Background
As the demand of dc electrical products continues to increase, air conditioning electrical products based on dc power are gradually innovated and developed. However, compared with the alternating current input power supply, the direct current power supply has the advantage that the polarity of the input power supply must be distinguished so as to prevent the air conditioner controller from being burnt out and even burst due to the reverse polarity connection of the input power supply.
In view of the above problems, the following solutions are generally adopted in the related art:
fig. 1 is a diode-based direct current power supply reverse connection prevention circuit, which is implemented by a common unipolar diode through the unidirectional conduction characteristic of the diode. The access method is simple and reliable, but when the input current is large, the loss of the diode is large, the heating is serious, and the problem of low power conversion efficiency exists.
Fig. 2 is a circuit for preventing reverse connection of a direct current power supply based on a rectifier bridge, which is implemented by adding a rectifier bridge device at an input end and realizing reverse connection prevention of the circuit through bridge rectification by using the unidirectional conduction characteristic of a diode. The circuit can work normally no matter how the input end is connected with the power supply. However, since the load current needs to pass through two diodes to form a loop every time, the power consumption of the rectifier bridge type reverse connection prevention protection circuit is twice that of the diode tube type reverse connection prevention protection circuit, and the problem of low efficiency also exists.
The inventor researches and discovers that: in the anti-reverse connection circuit, under the condition that the power supply current is constant, the power supply conversion efficiency is related to the conduction impedance of the diode; the larger the on-resistance, the lower the power conversion efficiency. On the other hand, the on-resistance of an insulated gate field effect transistor (MOS) is smaller than that of a diode, and therefore, if the MOS is used instead of the diode, it is possible to improve the power conversion efficiency. When the insulated gate field effect transistor or other controllable switch units are used in the reverse connection preventing circuit, a starting voltage is generated under the condition that the power supply is connected positively to conduct the controllable switch units, and the mode that the controllable switch units are switched off without generating the starting voltage under the condition that the power supply is connected reversely can replace a diode to play a role in preventing the reverse connection of the direct-current power supply. However, during the course of continued research it was found that: in an actual dc power grid, a dc output voltage of the dc power grid has voltage fluctuation, and particularly, when the voltage fluctuation reaches a lower voltage level, the control terminal of the controllable switch unit may not reach the turn-on voltage, which may cause abnormal turn-off of the controllable switch unit, thereby affecting the operation of the load device.
Disclosure of Invention
The invention provides a direct-current power supply anti-reverse connection circuit with a self-checking interlocking anti-interference function, which at least solves the problem that the direct-current power supply anti-reverse connection circuit based on a controllable switch unit in the related art is low in reliability due to voltage fluctuation.
The embodiment of the invention provides a direct-current power supply reverse connection prevention circuit, which comprises: the direct current voltage divider comprises a direct current input end, a direct current output end, a controllable switch unit, a first voltage dividing unit, an isolation unit, a switch power supply and a second voltage dividing unit, wherein the first voltage dividing unit is connected between the direct current input end and a public end, and a first voltage dividing end is led out; the input end of the switching power supply is connected with the direct current input end; the second voltage division unit is connected between the output end and the public end of the switching power supply and leads out a second voltage division end; the control end of the controllable switch unit is connected with the first voltage division end, the first switch end of the controllable switch unit is connected with the direct current output end, and the second switch end of the controllable switch unit is connected with the common end; one end of the isolation unit is connected with the control end of the controllable switch unit, the other end of the isolation unit is connected with the second voltage division end, and the isolation unit is used for isolating voltage signals on the first voltage division end and the second voltage division end.
Optionally, the switching power supply is configured to convert a dc input voltage at the dc input terminal into a voltage of a predetermined voltage level, and implement a voltage stabilizing function.
Optionally, the first voltage division unit includes: the circuit comprises a first resistor R1 and a second resistor R2, wherein one end of the first resistor R1 is connected with a direct current input end, and the other end of the first resistor R1 is connected with a first voltage division end; one end of the second resistor R2 is connected to the first voltage dividing terminal, and the other end of the second resistor R2 is connected to the common terminal.
Optionally, the circuit further comprises: and one end of a third resistor R3, one end of a third resistor R3 is connected with the control end of the controllable switch unit, and the other end of the third resistor R3 is connected with the first voltage division end.
Optionally, the first voltage division unit further includes: one end of the first capacitor C1 is connected to the first voltage dividing terminal, and the other end of the first capacitor C1 is connected to the common terminal, of the first capacitor C1.
Optionally, the first voltage division unit further includes: and the cathode of the voltage-stabilizing diode D1 and the cathode of the voltage-stabilizing diode D1 are connected with the first voltage-dividing end, and the anode of the voltage-stabilizing diode D1 is connected with the common end.
Optionally, the isolation unit comprises: and the cathode of the diode D2, the cathode of the diode D2 are connected with the control end of the controllable switch unit, and the anode of the diode D2 is connected with the second voltage division end.
Optionally, the circuit further comprises: a fourth resistor R4 and a second capacitor C2, wherein one end of the fourth resistor R4 is connected to the first switch end of the controllable switch unit, the other end of the fourth resistor R4 is connected to one plate of the second capacitor C2, and the other plate of the second capacitor C2 is connected to the second switch end of the controllable switch unit.
Optionally, the controllable switch unit is an insulated gate field effect transistor Q1, wherein the control terminal of the controllable switch unit is a gate of an insulated gate field effect transistor Q1, the first switch terminal of the controllable switch unit is a source of an insulated gate field effect transistor Q1, and the second switch terminal of the controllable switch unit is a drain of an insulated gate field effect transistor Q1.
Optionally, the second voltage division unit includes: the circuit comprises a fifth resistor R5, a triode Q2 and a sixth resistor R6, wherein one end of the fifth resistor R5 is connected with an emitter of the triode Q2, and the other end of the fifth resistor R5 is connected with a common end; one end of a sixth resistor R6 is connected with the output end of the switching power supply, and the other end of the sixth resistor R6 is connected with the base electrode of the triode Q2; the collector of the triode Q2 is connected with the output end of the switching power supply; the emitter of transistor Q2 is the second voltage divider.
Optionally, the second voltage division unit includes: the circuit comprises a fifth resistor R5, a triode Q2 and a control chip, wherein one end of the fifth resistor R5 is connected with an emitting electrode of the triode Q2, and the other end of the fifth resistor R5 is connected with a common end; the control chip is powered by a switching power supply, and the control end of the control chip is connected with the base electrode of the triode Q2; the collector of the triode Q2 is connected with the output end of the switching power supply; the emitter of transistor Q2 is the second voltage divider.
Optionally, the second voltage division unit further includes: and one plate of a third capacitor C3, a third capacitor C3 and the other plate of the third capacitor are connected with the common end and the emitter of the triode Q2 respectively.
According to the direct-current power supply reverse connection preventing circuit with the self-checking interlocking anti-interference function, when a direct-current power supply is reversely connected, because the potential of a direct-current output end is equal to that of a common end, no potential difference exists between the two ends of a first voltage division unit and the two ends of a second voltage division unit, no voltage signal exists on the first voltage division end and the second voltage division end, a controllable switch unit cannot be conducted, a positive input signal loaded on the direct-current output end cannot be connected into a circuit loop, and a load connected into the circuit cannot work; when the direct-current power supply is connected positively, as long as the voltage signal of the first voltage division end obtained by voltage division from the direct-current input end and the voltage signal of the second voltage division end obtained by voltage division from the output end of the switching power supply are obtained, any one of the two voltage signals can reach the starting voltage of the controllable switching unit, and then the controllable switching unit can be switched on. The problem of low reliability of the direct-current power supply reverse connection prevention circuit based on the controllable switch unit due to voltage fluctuation is solved, and the reliability of the direct-current power supply reverse connection prevention circuit is improved.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the invention without limiting the invention. In the drawings:
fig. 1 is a topological structure diagram of a diode-based dc power supply reverse connection preventing circuit according to the related art;
fig. 2 is a topology structure diagram of a rectifier bridge based dc power supply anti-reverse connection circuit according to the related art;
FIG. 3 is a topology diagram of a DC power supply anti-reverse connection circuit with self-checking interlock anti-interference function according to an embodiment of the invention;
FIG. 4 is a first preferred topology structure diagram of a DC power supply anti-reverse connection circuit with self-checking interlock anti-interference function according to an embodiment of the present invention;
FIG. 5 is a second preferred topology structure diagram of the anti-reverse connection circuit of the DC power supply with self-checking interlock anti-interference function according to the embodiment of the invention;
fig. 6 is a flowchart of the operation of the anti-reverse connection circuit of the dc power supply with self-checking interlock anti-interference function according to the embodiment of the invention.
Detailed Description
Features and exemplary embodiments of various aspects of the present invention will be described in detail below, and in order to make objects, technical solutions and advantages of the present invention more apparent, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. It will be apparent to one skilled in the art that the present invention may be practiced without some of these specific details. The following description of the embodiments is merely intended to provide a better understanding of the present invention by illustrating examples of the present invention.
It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.
In this embodiment, an anti-reverse-connection circuit for a dc power supply with self-checking, interlocking and anti-interference functions is provided, and fig. 3 is a topology structure diagram of an anti-reverse-connection circuit for a dc power supply with self-checking, interlocking and anti-interference functions according to an embodiment of the present invention, as shown in fig. 3, the anti-reverse-connection circuit for a dc power supply includes: the direct current voltage divider comprises a direct current input end 10, a direct current output end 20, a controllable switch unit 30, a first voltage dividing unit 40, an isolation unit 50, a switch power supply 60 and a second voltage dividing unit 70, wherein the first voltage dividing unit 40 is connected between the direct current input end 10 and a public end, and a first voltage dividing end is led out; the input end of the switching power supply 60 is connected with the direct current input end 10; the second voltage division unit 70 is connected between the output terminal and the common terminal of the switching power supply 60, and leads out a second voltage division terminal; the control end of the controllable switch unit 30 is connected with the first voltage division end, the first switch end of the controllable switch unit 30 is connected with the direct current output end 20, and the second switch end of the controllable switch unit 30 is connected with the common end; one end of the isolation unit 50 is connected to the control end of the controllable switch unit 30, the other end of the isolation unit 50 is connected to the second voltage-dividing end, and the isolation unit 50 is configured to isolate voltage signals at the first voltage-dividing end and the second voltage-dividing end.
Through the circuit, when the direct-current power supply is reversely connected, because the potential of the direct-current output end is equal to that of the common end, no potential difference exists between the two ends of the first voltage division unit and the second voltage division unit, no voltage signal exists between the first voltage division end and the second voltage division end, the controllable switch unit cannot be conducted, the positive input signal loaded on the direct-current output end cannot be connected into a circuit loop, and a load connected into the circuit cannot work; when the direct-current power supply is connected positively, as long as the voltage signal of the first voltage division end obtained by voltage division from the direct-current input end and the voltage signal of the second voltage division end obtained by voltage division from the output end of the switching power supply are obtained, any one of the two voltage signals can reach the starting voltage of the controllable switching unit, and then the controllable switching unit can be switched on. The problem of low reliability of the direct-current power supply reverse connection prevention circuit based on the controllable switch unit due to voltage fluctuation is solved, and the reliability of the direct-current power supply reverse connection prevention circuit is improved.
It should be noted that, according to the circuit topology structure diagram provided in this embodiment, in combination with a specific application scenario of the dc power supply reverse connection prevention circuit, a general circuit design theory knowledge is applied to determine a specific type and parameters of each component in this embodiment, so that the specific type and parameters of each component are not illustrated in this embodiment.
Alternatively, the switching power supply 60 is configured to convert the dc input voltage at the dc input terminal 10 into a voltage of a predetermined voltage level and implement a voltage stabilizing function. The switching power supply 60 with the voltage stabilizing function can ensure the stability of the voltage signal at the second voltage-dividing end, and further improve the reliability of the reverse connection preventing circuit of the direct-current power supply of the embodiment.
Fig. 4 is a preferred topology structure diagram of the dc power supply anti-reverse connection circuit with self-checking interlock anti-interference function according to the embodiment of the present invention. The dc power supply reverse connection prevention circuit of the present embodiment will be described and explained with reference to fig. 4.
Optionally, the voltage dividing unit adopts a mode of dividing voltage by a plurality of resistors, for example, the first voltage dividing unit 40 includes: the circuit comprises a first resistor R1 and a second resistor R2, wherein one end of the first resistor R1 is connected with the direct-current input end 10, and the other end of the first resistor R1 is connected with a first voltage division end; one end of the second resistor R2 is connected to the first voltage dividing terminal, and the other end of the second resistor R2 is connected to the common terminal.
Optionally, the circuit further comprises: one end of a third resistor R3, a third resistor R3 is connected with the control end of the controllable switch unit 30, and the other end of the third resistor R3 is connected with the first voltage-dividing end. The third resistor R3 is used to limit the current flowing from the first voltage dividing terminal to the control terminal of the controllable switching unit.
Optionally, the first voltage division unit 40 further includes: one end of the first capacitor C1 is connected to the first voltage dividing terminal, and the other end of the first capacitor C1 is connected to the common terminal, of the first capacitor C1. The first capacitor C1 is used for filtering.
Optionally, the first voltage division unit 40 further includes: and the cathode of the voltage-stabilizing diode D1 and the cathode of the voltage-stabilizing diode D1 are connected with the first voltage-dividing end, and the anode of the voltage-stabilizing diode D1 is connected with the common end. The zener diode D1 is used to stabilize the voltage across the second resistor R2, and the voltage across the second resistor R2 is the voltage across the first voltage-dividing terminal.
Optionally, the isolation unit 50 includes: the diode D2 has a cathode of the diode D2 connected to the control terminal of the controllable switch unit 30 and an anode of the diode D2 connected to the second voltage-dividing terminal.
Optionally, the circuit further comprises: a fourth resistor R4 and a second capacitor C2, wherein one end of the fourth resistor R4 is connected to the first switch end of the controllable switch unit 30, the other end of the fourth resistor R4 is connected to one plate of the second capacitor C2, and the other plate of the second capacitor C2 is connected to the second switch end of the controllable switch unit 30. The fourth resistor R4 and the second capacitor C2 form a soft start circuit; the second capacitor C2 also acts as a filter.
The controllable switching unit 30 includes, but is not limited to: triodes, insulated gate field effect transistors, relays, and the like. In this embodiment, in order to reduce the loss of the controllable switch unit 30 to the power supply, optionally, the controllable switch unit 30 is an insulated gate field effect transistor Q1, wherein the control terminal of the controllable switch unit 30 is a gate of an insulated gate field effect transistor Q1, the first switch terminal of the controllable switch unit 30 is a source of an insulated gate field effect transistor Q1, and the second switch terminal of the controllable switch unit 30 is a drain of an insulated gate field effect transistor Q1.
Referring to fig. 5, the second voltage dividing unit may also adopt a manner of dividing voltage by a plurality of resistors. Because the output voltage of the switching power supply is relatively stable, the voltage level of the voltage signal at the second voltage division end can be kept stable by replacing the voltage division resistor with a triode with fixed conduction voltage drop. For this, in the present embodiment, the second pressure dividing unit 70 includes: the circuit comprises a fifth resistor R5, a triode Q2 and a sixth resistor R6, wherein one end of the fifth resistor R5 is connected with an emitter of the triode Q2, and the other end of the fifth resistor R5 is connected with a common end; one end of the sixth resistor R6 is connected to the output end of the switching power supply 60, and the other end of the sixth resistor R6 is connected to the base of the transistor Q2; the collector of the triode Q2 is connected with the output terminal of the switching power supply 60; the emitter of transistor Q2 is the second voltage divider.
Referring to fig. 4, the base voltage signal of transistor Q2 may also be generated directly by the control chip, which is preferably an MCU of the device in which the anti-reverse connection circuit is located. Alternatively, the second voltage division unit 70 includes: the circuit comprises a fifth resistor R5, a triode Q2 and a control chip MCU, wherein one end of the fifth resistor R5 is connected with an emitting electrode of the triode Q2, and the other end of the fifth resistor R5 is connected with a common end; the control chip MCU is powered by the switching power supply 60, and the control end of the control chip MCU is connected with the base electrode of the triode Q2; the collector of the triode Q2 is connected with the output terminal of the switching power supply 60; the emitter of transistor Q2 is the second voltage divider.
Optionally, the second voltage division unit 70 further includes: and one plate of a third capacitor C3, a third capacitor C3 and the other plate of the third capacitor are connected with the common end and the emitter of the triode Q2 respectively. The third capacitor C3 is used for filtering.
Fig. 6 is a flowchart of the operation of the dc power supply anti-reverse connection circuit with self-checking interlock anti-interference function according to the embodiment of the present invention, and the operation of this embodiment will be described with reference to fig. 4 and 6.
In the dc power supply reverse connection prevention circuit shown in fig. 4:
without increasing the interlock signal generated by the MCU, the Q1 turn-on condition is affected by the input supply voltage fluctuation in the case of large fluctuation of the input supply voltage, but without affecting the stability of the VCC voltage. When the input voltage fluctuates to a lower limit value, the R1 resistor and the R2 resistor are subjected to resistor voltage division, the gate voltage of a MOS transistor Q1 obtained on the R2 is smaller than the starting voltage, the Q1 is abnormally disconnected, the power supply of a circuit is cut off, and the normal operation is influenced.
If the interlock signal generated by the MCU is added, the Q1 conduction condition will not be affected by the input supply voltage fluctuation under the condition that the input supply voltage has large fluctuation but the VCC voltage stability is not affected. When the input voltage fluctuates to the lower limit value, even if the gate voltage of the MOS transistor Q1 obtained on the R2 is smaller than the turn-on voltage, the MCU can generate a control signal under the condition of the stable power source VCC, so that the Q2 is turned on, and after the Q2 is turned on, a voltage close to VCC is generated on the R5 resistor, and at this time, the interlock signal is at a high level. After the interlock signal passes through D2, the gate voltage of Q1 is controlled, so that Q1 obtains the turn-on voltage again, and the conduction of Q1 is maintained. Q1 is conducted, and the circuit power supply supplies power normally without influencing normal operation.
Therefore, the anti-reverse connection circuit for the direct current power supply provided by the embodiment can prevent the Q1 from being turned off by misoperation when the external power supply is subjected to surge interference.
Referring to fig. 4, R1 to R5 are resistance devices; C1-C3 are capacitor devices; a D1 zener diode; d2 is a switching diode; q1 is MOS transistor (G: gate, S: source, D: drain); q2 is a triode; VCC is a stable power supply obtained by converting Vout through voltage reduction and linear voltage stabilization of the switching power supply; the MCU is a main chip of the controller and can download a control program; load is the Load; VDC + is the positive pole of the DC power input, and GND is the negative pole of the DC power input. D1 is a voltage stabilizing diode, and C1 is a filter capacitor for stabilizing the voltage obtained by the voltage dividing resistor R2. R3 is a drive current limiting resistor for limiting the current magnitude of the G gate control signal through the Q1 device. D2 is a switching diode used to isolate the interlock signal from the enabled voltage signal obtained by the R2 voltage divider resistor. R4 and C2 form an RC soft start circuit, and can absorb noise interference generated by a switching signal of a Q1 device.
When the wiring is correct, the resistors R1 and R2 are subjected to resistor voltage division, a starting voltage capable of starting the MOS transistor Q1 is obtained on the resistor R2, so that the Q1 is conducted, and the power VDC + reaches the power GND through the Load to form a loop and normally supply power.
Under the condition that the input power supply voltage has large fluctuation but the stability of the VCC voltage is not influenced, the conduction condition of Q1 is not influenced by the fluctuation of the input power supply voltage, and the process is called as 'circuit anti-interference', so that the malfunction of the MOS switch caused by the power supply interference can be effectively prevented.
Referring to fig. 6, the term "circuit interference resistance" in this embodiment specifically means: under the condition that a stable power supply VCC supplies power, the MCU can generate a control signal to enable the Q2 to be switched on, after the Q2 is switched on, the R5 resistor generates voltage close to VCC, the C3 is used for filtering after voltage division is carried out on the R5 resistor, and at the moment, the interlocking signal is at a high level. The term "self-checking interlock" in this embodiment means: after the interlock signal (namely the voltage signal at the second voltage division end) passes through the D2, the G grid voltage of the Q1 is controlled, so that the Q1 obtains the turn-on voltage again, and the Q1 is maintained to be conducted; the MCU sends a control command to maintain Q1 on.
When the wiring is wrong, the grid electrode of the Q1 device G cannot obtain starting voltage and is always in an off state, the power VDC + cannot reach the power GND through the Load to form a loop, no current exists in the circuit, and the circuit can be prevented from being burnt out and the controller can be prevented from being cracked.
The anti-reverse connection circuit of the direct current power supply provided by the embodiment can be applied to various electrical equipment using the direct current power supply, such as a direct current power supply air conditioner and the like.
In summary, the following beneficial effects can be achieved through the above embodiments and implementation manners of the present invention:
1. the controller is prevented from being burnt and the plates are prevented from being fried due to the fact that the polarity of the input power supply of the air conditioning unit is reversed;
2. the power consumption of the self device of the power supply anti-reverse circuit is reduced, and the working efficiency of the circuit is improved;
3. the switching signals of the controllable switching units are interlocked, so that the switching misoperation caused by surge interference of an external power supply is prevented.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (12)
1. A direct current power supply reverse connection prevention circuit is characterized by comprising: a direct current input end, a direct current output end, a controllable switch unit, a first voltage division unit, an isolation unit, a switch power supply and a second voltage division unit,
the first voltage division unit is connected between the direct current input end and the public end, and leads out a first voltage division end;
the input end of the switching power supply is connected with the direct current input end;
the second voltage division unit is connected between the output end of the switching power supply and the common end and leads out a second voltage division end;
the control end of the controllable switch unit is connected with the first voltage division end, the first switch end of the controllable switch unit is connected with the direct current output end, and the second switch end of the controllable switch unit is connected with the public end;
one end of the isolation unit is connected with the control end of the controllable switch unit, the other end of the isolation unit is connected with the second voltage division end, and the isolation unit is used for isolating voltage signals on the first voltage division end and the second voltage division end.
2. The circuit of claim 1, wherein the switching power supply is configured to convert a dc input voltage at the dc input terminal into a voltage of a predetermined voltage level and perform a voltage stabilizing function.
3. The circuit of claim 1, wherein the first voltage division unit comprises: a first resistor (R1), a second resistor (R2), wherein,
one end of the first resistor (R1) is connected with the direct current input end, and the other end of the first resistor (R1) is connected with the first voltage division end;
one end of the second resistor (R2) is connected to the first voltage dividing terminal, and the other end of the second resistor (R2) is connected to the common terminal.
4. The circuit of claim 3, further comprising: a third resistor (R3), one end of the third resistor (R3) being connected to the control terminal of the controllable switch unit, the other end of the third resistor (R3) being connected to the first voltage-dividing terminal.
5. The circuit of claim 3, wherein the first voltage division unit further comprises: a first capacitor (C1), one end of the first capacitor (C1) being connected to the first voltage dividing terminal, the other end of the first capacitor (C1) being connected to the common terminal.
6. The circuit of claim 3, wherein the first voltage division unit further comprises: a zener diode (D1), a cathode of the zener diode (D1) being connected to the first voltage dividing terminal, and an anode of the zener diode (D1) being connected to the common terminal.
7. The circuit of claim 1, wherein the isolation unit comprises: a diode (D2), a cathode of the diode (D2) being connected to the control terminal of the controllable switching unit, and an anode of the diode (D2) being connected to the second voltage-dividing terminal.
8. The circuit of claim 1, further comprising: a fourth resistor (R4) and a second capacitor (C2), wherein,
one end of the fourth resistor (R4) is connected to the first switch end of the controllable switch unit, the other end of the fourth resistor (R4) is connected to one plate of the second capacitor (C2), and the other plate of the second capacitor (C2) is connected to the second switch end of the controllable switch unit.
9. The circuit according to claim 1, characterized in that the controllable switching unit is an insulated gate field effect transistor (Q1), wherein,
the control end of the controllable switch unit is the grid electrode of the insulated gate field effect transistor (Q1), the first switch end of the controllable switch unit is the source electrode of the insulated gate field effect transistor (Q1), and the second switch end of the controllable switch unit is the drain electrode of the insulated gate field effect transistor (Q1).
10. The circuit of claim 1, wherein the second voltage divider unit comprises:
a fifth resistor (R5), a triode (Q2) and a sixth resistor (R6), wherein,
one end of the fifth resistor (R5) is connected with the emitter of the triode (Q2), and the other end of the fifth resistor (R5) is connected with the common end;
one end of the sixth resistor (R6) is connected with the output end of the switch power supply, and the switch power supply
The other end of the sixth resistor (R6) is connected with the base of the triode (Q2);
the collector of the triode (Q2) is connected with the output end of the switching power supply; the emitter of the triode (Q2) is the second voltage division end.
11. The circuit of claim 1, wherein the second voltage divider unit comprises: a fifth resistor (R5), a triode (Q2) and a control chip, wherein,
one end of the fifth resistor (R5) is connected with the emitter of the triode (Q2), and the other end of the fifth resistor (R5) is connected with the common end;
the control chip is powered by the switching power supply, and the control end of the control chip is connected with the base electrode of the triode (Q2);
the collector of the triode (Q2) is connected with the output end of the switching power supply; the emitter of the triode (Q2) is the second voltage division end.
12. The circuit of claim 10 or 11, wherein the second voltage dividing unit further comprises: a third capacitor (C3), one plate of the third capacitor (C3) is connected with the common end, and the other plate of the third capacitor is connected with the emitter of the triode (Q2).
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201910521988.9A CN110086162B (en) | 2019-06-17 | 2019-06-17 | Direct-current power supply anti-reverse connection circuit with self-checking interlocking anti-interference function |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201910521988.9A CN110086162B (en) | 2019-06-17 | 2019-06-17 | Direct-current power supply anti-reverse connection circuit with self-checking interlocking anti-interference function |
Publications (2)
Publication Number | Publication Date |
---|---|
CN110086162A CN110086162A (en) | 2019-08-02 |
CN110086162B true CN110086162B (en) | 2020-04-28 |
Family
ID=67424366
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN201910521988.9A Active CN110086162B (en) | 2019-06-17 | 2019-06-17 | Direct-current power supply anti-reverse connection circuit with self-checking interlocking anti-interference function |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN110086162B (en) |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN111342442A (en) * | 2020-04-07 | 2020-06-26 | 达闼机器人有限公司 | Reverse connection prevention power supply protection circuit, power supply management system and robot |
CN112688276A (en) * | 2020-12-28 | 2021-04-20 | 深圳市安帕尔科技有限公司 | Air station alarm host circuit and air station equipment |
Family Cites Families (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN101872971A (en) * | 2010-07-02 | 2010-10-27 | 北京星网锐捷网络技术有限公司 | Reverse-connection preventing circuit, reverse-connection preventing processing method and communication equipment |
CN103904620B (en) * | 2012-12-28 | 2018-09-14 | 南京中兴软件有限责任公司 | A kind of DC supply input counnter attack fills circuit and method |
JP6070425B2 (en) * | 2013-06-06 | 2017-02-01 | 株式会社デンソー | Surge protection circuit for injector drive |
CN205231727U (en) * | 2015-12-10 | 2016-05-11 | 河北世纪恒兴电子技术有限公司 | Switching power supply output connects battery to join conversely protection automatic control circuit |
CN105703614B (en) * | 2015-12-30 | 2018-08-21 | 深圳市国耀电子科技股份有限公司 | A kind of reverse connection preventing pours in down a chimney protection circuit |
CN105898935A (en) * | 2016-06-14 | 2016-08-24 | 安徽师范大学 | Anti-reverse connection and soft-starting circuit for LED drive power supply |
CN107359608A (en) * | 2017-09-05 | 2017-11-17 | 山东超越数控电子有限公司 | A kind of direct current prevents reversed protection circuit |
CN107845998B (en) * | 2017-11-10 | 2020-01-07 | 西安微电子技术研究所 | Input power supply health detection and management circuit in power supply parallel redundancy system |
CN107947557B (en) * | 2017-12-05 | 2023-07-04 | 合肥华耀电子工业有限公司 | Soft start circuit for resisting overvoltage and undervoltage surges |
CN207625441U (en) * | 2017-12-05 | 2018-07-17 | 合肥华耀电子工业有限公司 | A kind of soft starting circuit of anti-over-pressed, under-voltage surge |
-
2019
- 2019-06-17 CN CN201910521988.9A patent/CN110086162B/en active Active
Also Published As
Publication number | Publication date |
---|---|
CN110086162A (en) | 2019-08-02 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US6608768B2 (en) | Use of a rectified image voltage for controlling the switch on the primary side of a switched-mode power supply | |
JP6554321B2 (en) | Insulation synchronous rectification type DC / DC converter and synchronous rectification controller thereof, power supply device using the same, power supply adapter, and electronic device | |
EP2618443A1 (en) | Dynamic damper and lighting driving circuit comprising the dynamic damper | |
CN109342973B (en) | Direct current power supply input state monitoring circuit and system | |
CN110086162B (en) | Direct-current power supply anti-reverse connection circuit with self-checking interlocking anti-interference function | |
KR20140081666A (en) | Start-up circuit for a switching power supply | |
TW201815048A (en) | Line-voltage detection circuit and relevant detection method | |
RU2661311C2 (en) | Electronic circuit and method of operation of electronic circuit | |
KR100522017B1 (en) | Fault control circuit for switched power supply | |
CN112510985A (en) | Soft start circuit and power supply circuit | |
JP2017070028A (en) | Semiconductor device | |
JP6449490B2 (en) | DC fan control system and DC fan | |
US10355612B2 (en) | Flyback power converter circuit and secondary side controller circuit thereof | |
US9350251B2 (en) | Power conversion apparatus and over power protection method thereof | |
CN104995576A (en) | A non-isolated ac to dc power device | |
CN105680418A (en) | Single-phase AC motor protection circuit, fan and air conditioner | |
CN108631271B (en) | Overcurrent protection control circuit | |
CN217159266U (en) | Power supply circuit and electrical equipment | |
CN206226397U (en) | IGBT protection circuit and electromagnetism stove | |
JP3826804B2 (en) | Dual power supply system | |
CN213991098U (en) | LED drive circuit with protection function | |
CN206821036U (en) | IGBT protection circuit and electromagnetism stove | |
CN107027207B (en) | IGBT protection circuit and induction cooker | |
JP2011176986A (en) | Life detecting circuit | |
CN112804791A (en) | PWM control anti-flashback circuit and LED driving power supply |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PB01 | Publication | ||
PB01 | Publication | ||
SE01 | Entry into force of request for substantive examination | ||
SE01 | Entry into force of request for substantive examination | ||
GR01 | Patent grant | ||
GR01 | Patent grant |