CN112701654A - Short-circuit protection device, circuit system and short-circuit protection method thereof - Google Patents
Short-circuit protection device, circuit system and short-circuit protection method thereof Download PDFInfo
- Publication number
- CN112701654A CN112701654A CN202011415068.8A CN202011415068A CN112701654A CN 112701654 A CN112701654 A CN 112701654A CN 202011415068 A CN202011415068 A CN 202011415068A CN 112701654 A CN112701654 A CN 112701654A
- Authority
- CN
- China
- Prior art keywords
- circuit
- short
- power supply
- fault
- line
- 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.)
- Granted
Links
Images
Classifications
-
- 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
- Y04—INFORMATION OR COMMUNICATION TECHNOLOGIES HAVING AN IMPACT ON OTHER TECHNOLOGY AREAS
- Y04S—SYSTEMS INTEGRATING TECHNOLOGIES RELATED TO POWER NETWORK OPERATION, COMMUNICATION OR INFORMATION TECHNOLOGIES FOR IMPROVING THE ELECTRICAL POWER GENERATION, TRANSMISSION, DISTRIBUTION, MANAGEMENT OR USAGE, i.e. SMART GRIDS
- Y04S10/00—Systems supporting electrical power generation, transmission or distribution
- Y04S10/50—Systems or methods supporting the power network operation or management, involving a certain degree of interaction with the load-side end user applications
- Y04S10/52—Outage or fault management, e.g. fault detection or location
Landscapes
- Emergency Protection Circuit Devices (AREA)
Abstract
The invention discloses a short-circuit protection device, a circuit system and a short-circuit protection method thereof, wherein the device comprises: a short-circuit protection unit; the short-circuit protection unit is arranged between a power supply and a load of a circuit system and is configured to detect whether a power supply line of the power supply and the load have short-circuit faults or not; and cutting off a portion in which a short-circuit fault occurs from the circuit system and displaying a position of the portion in which the short-circuit fault occurs in the circuit system, in the case where the short-circuit fault occurs in at least one of a power supply line of the power supply and the load. According to the scheme, when a circuit fails, the fault part can be cut off and the fault position can be displayed, so that the maintenance is convenient.
Description
Technical Field
The invention belongs to the technical field of electronic circuits, particularly relates to a short-circuit protection device, a circuit system and a short-circuit protection method thereof, and particularly relates to a circuit for short-circuit grading protection and short-circuit point detection and a control method thereof.
Background
When a short-circuit fault occurs on a circuit, the power supply can be cut off, but the position of the short-circuit fault in the circuit cannot be positioned, so that the maintenance is inconvenient.
The above is only for the purpose of assisting understanding of the technical aspects of the present invention, and does not represent an admission that the above is prior art.
Disclosure of Invention
The invention aims to provide a short-circuit protection device, a circuit system and a short-circuit protection method thereof, which are used for solving the problems that when a short-circuit fault occurs in a circuit, a power supply is cut off, a short-circuit fault point cannot be positioned, and the maintenance is inconvenient, and achieving the effect of conveniently maintaining by cutting off a fault part and displaying a fault position when the circuit fails.
The invention provides a short-circuit protection device, comprising: a short-circuit protection unit; the short-circuit protection unit is arranged between a power supply and a load of a circuit system and is configured to detect whether a power supply line of the power supply and the load have short-circuit faults or not; and cutting off a portion in which a short-circuit fault occurs from the circuit system and displaying a position of the portion in which the short-circuit fault occurs in the circuit system, in the case where the short-circuit fault occurs in at least one of a power supply line of the power supply and the load.
In some embodiments, a power line of the power supply comprises: a main power supply line of the power supply and a branch power supply line of the power supply; the number of the short-circuit protection units is more than one; one or more short-circuit protection units, comprising: the short-circuit protection unit is arranged on the power supply main line, and the short-circuit protection unit is arranged on the power supply branch line.
In some embodiments, the power supply, comprises: a first sub power supply and a second sub power supply; the power supply main line comprises: a first main line and a second main line; the power supply branch line includes: a first branch line and a second branch line; the first sub power supply is connected to the first main line; the first branch line and the second branch line are two parallel branch lines led out from the first main line; the second sub power supply is connected to the second main line; at least one short-circuit protection unit is arranged on the first main line and between the first sub-power supply and the first branch line; at least one short-circuit protection unit is arranged on the first branch line and the second branch line respectively; and at least one short-circuit protection unit is arranged on the second main line.
In some embodiments, the power supply main line includes: a first main line and a second main line arranged in parallel; at least one short-circuit protection unit is arranged on the first main line; and at least one short-circuit protection unit is arranged on the second main line.
In some embodiments, in a direction from the power source to the load, one or more short-circuit protection units perform one or more short-circuit protection on a power supply line of the power source and the load.
In some embodiments, the short-circuit protection unit includes: the short circuit detection module, the driving module and the fault display and switch unit are arranged on the circuit board; the short-circuit detection module is configured to detect whether a short-circuit fault occurs in a power supply line of the power supply and the load; the driving module is configured to initiate a driving signal to the fault display and switch unit when at least one of a power supply line of the power supply and the load has a short-circuit fault; the fault display and switch unit is configured to cut off a portion where a short-circuit fault occurs from the circuit system and display a position of the portion where the short-circuit fault occurs in the circuit system, in a case where the driving signal is received.
In some embodiments, the short detection module comprises: the device comprises a sampling module, a comparison module and an output module; wherein, the short circuit detection module detects whether the power supply line of power and the load have short circuit fault, including: the sampling module is configured to sample current voltages of a power supply line of the power supply and the load; the comparison module is configured to compare the current voltage with a preset reference voltage so as to generate a short-circuit signal when the current voltage is lower than the reference voltage; the output module is configured to output the short circuit signal to the driving module.
In some embodiments, the drive module comprises: a first switch module; the driving module initiates a driving signal to the fault display and switch unit, and the driving module comprises: and under the condition of receiving the short-circuit signal, the first switch module is turned on to generate a driving signal.
In some embodiments, the fault display and switch unit comprises: the display module comprises a first switch module and a display module; wherein, the fault display and switch unit cuts off a part with a short-circuit fault from the circuit system and displays the position of the part with the short-circuit fault in the circuit system, comprising: the second switch module is configured to disconnect the second switch module itself to cut off a power supply line of the power supply to a rear-stage circuit of the second switch module when the driving signal is received; the display module is configured to enable the display module to be powered on and display under the condition that the driving signal is received, so that the position of a part of the circuit system where the short-circuit fault occurs is displayed in the circuit system.
In accordance with another aspect of the present invention, there is provided a circuit system, including: the short-circuit protection device described above.
In another aspect, the present invention provides a short-circuit protection method for a circuit system, including: the method comprises the steps that a short-circuit protection unit is arranged between a power supply and a load of a circuit system, and whether a power supply line of the power supply and the load have short-circuit faults or not is detected; and cutting off a portion in which a short-circuit fault occurs from the circuit system and displaying a position of the portion in which the short-circuit fault occurs in the circuit system, in the case where the short-circuit fault occurs in at least one of a power supply line of the power supply and the load.
Therefore, according to the scheme of the invention, at least one stage of short-circuit protection unit circuit is arranged on each power main line and each power branch line between the power main circuit and the load, so that when different points are in fault, the short-circuit protection unit circuit closest to the fault position can perform short-circuit protection in time, the fault point is cut off, the fault position is displayed, and the fault part can be cut off and the fault position is displayed when the circuit is in fault, so that the maintenance is facilitated.
Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.
The technical solution of the present invention is further described in detail by the accompanying drawings and embodiments.
Drawings
Fig. 1 is a schematic structural diagram of a short-circuit protection device according to an embodiment of the present invention;
FIG. 2 is a schematic diagram of an embodiment of a minimum system level protection circuit;
FIG. 3 is a schematic structural diagram of an embodiment of a short-circuit protection unit;
FIG. 4 is a schematic structural diagram of another embodiment of a short-circuit protection unit;
FIG. 5 is a schematic diagram of an embodiment of a minimum system level protection integrated circuit;
FIG. 6 is a schematic structural diagram of an embodiment in which the relay is replaced by an IGBT;
FIG. 7 is a schematic diagram of an embodiment in which the relay is replaced by a MOSFET;
FIG. 8 is a schematic diagram of an embodiment in which the relay is replaced with a transistor;
FIG. 9 is a schematic diagram of an embodiment in which the comparator is replaced with an inverter;
fig. 10 is a schematic structural diagram of an embodiment of a circuit in which a comparator is replaced by a triode.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be clearly and completely described below with reference to the specific embodiments of the present invention and the accompanying drawings. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. 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.
According to an embodiment of the present invention, a short circuit protection device is provided. Referring to fig. 1, a schematic diagram of an embodiment of the apparatus of the present invention is shown. The short-circuit protection device may include: and a short-circuit protection unit (such as a short-circuit protection unit circuit).
The short-circuit protection unit is arranged between a power supply and a load of a circuit system and is configured to detect whether a power supply line of the power supply and the load have short-circuit faults or not; and cutting off a portion in which a short-circuit fault occurs from the circuit system and displaying a position of the portion in which the short-circuit fault occurs in the circuit system, in the case where the short-circuit fault occurs in at least one of a power supply line of the power supply and the load.
Therefore, the short-circuit protection unit is arranged between the power supply and the load of the circuit system, so that the fault position can be accurately displayed, the fault can be removed, the problem troubleshooting is convenient, the position of the short-circuit fault in the circuit system can be accurately and timely displayed, and the maintenance is convenient.
In some embodiments, a power line of the power supply comprises: a main power supply line of the power supply, and a branch power supply line of the power supply. The power supply branch line is a branch power supply line from the power supply main line. The number of the loads is more than one. One or more of the loads, comprising: the power supply system comprises a first load powered by the power supply through the power supply main line, and a second load powered by the power supply through the power supply main line and the power supply branch line.
The number of the short-circuit protection units is more than one. One or more short-circuit protection units, comprising: the short-circuit protection unit is arranged on the power supply main line, and the short-circuit protection unit is arranged on the power supply branch line. Such as at least one of the short-circuit protection units, located between a power supply and a first load and arranged on the main power supply line. And the at least one short-circuit protection unit is positioned between the power supply and the second load and is arranged on the power supply branch line.
In some embodiments, the power supply, comprises: a first sub power supply and a second sub power supply. The power supply main line comprises: a first main line and a second main line. The power supply branch line includes: a first branch line and a second branch line. The first sub power supply is connected to the first main line. The first branch line and the second branch line are two parallel branch lines led out from the first main line. The second sub power supply is connected to the second main line.
At least one short-circuit protection unit is arranged on the first main line between the first sub-power supply and the first branch line. At least one short-circuit protection unit is arranged on the first branch line and the second branch line respectively. That is, at least one short-circuit protection unit is provided in the first branch line between the first sub-power supply and the load. And at least one short-circuit protection unit is arranged on the second branch line between the second sub-power supply and the load.
At least one short-circuit protection unit is arranged on the second main circuit, namely between the second sub-power supply and the load.
Therefore, the protection circuits are arranged on each power main line and each branch line and respectively correspond to two fault conditions of power main line short circuit and load short circuit, so that when faults occur in different places, the protection circuit closest to a fault point can work in time, the fault point is cut off, and normal work of other circuits is not influenced.
In some embodiments, the power supply main line includes: a first main line and a second main line arranged in parallel. At least one short-circuit protection unit is arranged on the first main line. And at least one short-circuit protection unit is arranged on the second main line.
In some embodiments, in a direction from the power source to the load, one or more short-circuit protection units perform one or more short-circuit protection on a power supply line of the power source and the load.
Specifically, in the short-circuit protection of more than two stages, the short circuit of the rear stage does not affect the circuit of the front stage, the short circuit of the same stage does not affect each other, and the short circuit of the front stage and the short circuit of the rear stage do not work.
For example: the minimum system protects the whole circuit in a grading way, and two short-circuit protection circuits are shared. Of course, in actual use, several more levels of protection can be added according to actual needs. The first fault and the third fault are preceded by primary protection, and secondary protection is performed between the first fault and the second fault.
When a fault occurs at the second fault, the normally closed contact of the relay K2 in the second short-circuit protection unit circuit is opened, the light emitting diode LED2 emits light to display the fault, the first fault and the third fault are still at high levels, the normally closed contact of the relay K1 in the first short-circuit protection unit circuit and the normally closed contact of the relay K3 in the third short-circuit protection unit circuit do not act, the light emitting diode LED1 in the first short-circuit protection unit circuit and the light emitting diode LED3 in the third short-circuit protection unit circuit are not conducted, namely, the front stage cannot be affected when the rear stage is short-circuited, and therefore the short-circuit point can be positioned at the second fault.
When the first fault position breaks down, the first fault rear-stage circuit is short-circuited and does not work, at the moment, the normally closed contact of the relay K1 in the first short-circuit protection unit circuit is disconnected, the light-emitting diode LED1 in the first short-circuit protection unit circuit emits light to display faults, other light-emitting diodes do not display, the fault point is positioned at the first fault position, and therefore the overall effect is achieved: the rear-stage short circuit does not affect the front-stage circuit, the short circuits of the same stage do not affect each other, the front-stage short circuit and the rear-stage short circuit do not work, and the light-emitting diode only can display at a fault position.
Therefore, by adopting a novel circuit short circuit grading protection circuit, the fault circuit can be effectively cut off in real time, the fault position can be displayed, and problems can be conveniently found and maintained.
In some embodiments, the short-circuit protection unit includes: a short circuit detection module (such as a short circuit detection circuit), a driving module (such as a driving circuit), and a fault display and switch unit (such as a fault display and switch circuit).
Wherein the short-circuit detection module is configured to detect whether a short-circuit fault occurs in a power supply line of the power supply and the load.
The driving module is configured to initiate a driving signal to the fault display and switch unit when at least one of a power supply line of the power supply and the load has a short-circuit fault.
The fault display and switch unit is configured to cut off a portion where a short-circuit fault occurs from the circuit system and display a position of the portion where the short-circuit fault occurs in the circuit system, in a case where the driving signal is received.
Specifically, in normal operation, the switch circuit is closed, and the current flows to the power source → the fault display and switch circuit → the load. When the load has short-circuit fault, the short-circuit detection circuit can detect the short-circuit signal, so that the short-circuit signal is transmitted to the drive circuit, and the drive circuit controls the fault display and the switch circuit in the switch circuit to be switched off and controls the fault display circuit in the fault display and switch circuit to display the fault signal.
In some embodiments, the short detection module comprises: a sampling module (e.g., resistor R5), a comparison module (e.g., comparator U1), and an output module (e.g., resistor R4).
Wherein, the short circuit detection module detects whether the power supply line of power and the load have short circuit fault, including:
the sampling module is configured to sample current voltages of a power supply line of the power supply and the load.
The comparison module is configured to compare the current voltage with a preset reference voltage so as to generate a short-circuit signal when the current voltage is lower than the reference voltage. The reference voltage can be obtained by dividing the voltage of the dc power supply VCC by the resistor R6 and the resistor R7.
The output module is configured to output the short circuit signal to the driving module.
In some embodiments, the drive module comprises: a first switching module (e.g., transistor Q2).
The driving module initiates a driving signal to the fault display and switch unit under the condition that at least one of a power supply line of the power supply and the load has a short-circuit fault, and the driving module comprises: and under the condition of receiving the short-circuit signal, the first switch module is turned on to generate a driving signal.
In some embodiments, the fault display and switch unit comprises: a second switch module (e.g., relay K1) and a display module (e.g., light emitting diode LED1, transistor Q1, resistor R1, resistor R2, resistor R3, etc.).
Wherein the fault display and switch unit, in case of receiving the driving signal, cuts off a portion where a short-circuit fault occurs from the circuit system and displays a position of the portion where the short-circuit fault occurs in the circuit system, includes:
the second switch module is configured to disconnect the second switch module itself to cut off a power supply line of the power supply to a subsequent circuit of the second switch module when the driving signal is received.
The display module is configured to enable the display module to be powered on and display under the condition that the driving signal is received, so that the position of a part of the circuit system where the short-circuit fault occurs is displayed in the circuit system.
Specifically, during normal operation: the normally closed contact of the relay K1 is closed, the current directly flows to the load from the power supply (i.e. the main power supply circuit), at this time, the voltage of the inverting input terminal of the comparator U1 is higher than the voltage of the non-inverting input terminal of the comparator U1, a low level is output to the base of the NPN triode Q2, the NPN triode Q2 is not conducted, the normally closed contact of the relay K1 is continuously kept in a closed state, the circuit normally works, at this time, the resistor R1, the resistor R2, the resistor R3, the light emitting diode LED1 and the NPN triode Q1 are short-circuited by the normally closed contact of the relay K1, so that the normally closed contact cannot work, and the.
When the load is short-circuited: the level of the inverting input terminal of the comparator U1 is pulled low, the voltage at the inverting input terminal of the comparator U1 is lower than that at the non-inverting input terminal of the comparator U1, and the comparator U1 outputs a high level. The NPN transistor Q2 is turned on, the normally closed contact of the relay K1 is opened, and current flows through the resistor R1, the light emitting diode LED1, the NPN transistor Q1, the resistor R2, and the resistor R3 to the load via the power supply (i.e., the main circuit of the power supply). The resistances of the resistor R1, the resistor R2 and the resistor R3 are as large as possible, so that the flowing current is small, the circuit loss can be reduced, and the effect of protecting a rear-stage circuit and a load is achieved.
Therefore, a simple short-circuit protection unit circuit is formed by only using a resistor, a capacitor, a triode, a light-emitting diode and a comparator; the comparator detects the short-circuit signal, so that the triode is utilized to turn on and off the circuit, the used devices are few, the cost is low, and the comparator can be widely used in a complex circuit system.
Through a large number of tests, the technical scheme of the invention is adopted, and at least one stage of short-circuit protection unit circuit is arranged on each power main line and each power branch line between the power main circuit and the load, so that when different points break down, the short-circuit protection unit circuit closest to the fault position can perform short-circuit protection in time, the fault point is cut off, the fault position is displayed, and when the circuit breaks down, the fault part can be cut off and the fault position can be displayed, so that the maintenance is convenient.
According to an embodiment of the invention, there is also provided a circuit system corresponding to the short-circuit protection device. The circuitry may include: the short-circuit protection device described above.
Short-circuit faults occur most easily on circuits (such as circuits of a controller), and once the short-circuit faults occur, burning or other serious damages are easily caused to elements (such as important elements, sensitive elements and the like on a circuit board) or loads on the circuit board of the controller, so that the controller cannot work normally. Although the power supply can be cut off when the short-circuit fault occurs in the circuit of the controller, the normal circuit and the load can be cut off, the fault analysis and the maintenance are not convenient due to the fact that the normal circuit and the load are enlarged and the actual position of the short-circuit point cannot be directly observed.
Therefore, when a part of circuits in the controller have short-circuit faults, the power supply is cut off, normal work of the part of circuits and loads which do not have the short-circuit faults in the circuits of the controller is influenced, short-circuit fault points cannot be located, and the short-circuit protection effect is poor.
In the related scheme, the short-circuit protection circuit has a complex structure and uses more devices, so the cost is higher, and the short-circuit protection circuit cannot be applied in a large amount in a complex circuit system due to the limitations of cost and space, so that fine grading protection of various important loads in the complex circuit system cannot be realized.
In some embodiments, the scheme of the invention provides a circuit for short-circuit grading protection and short-circuit point detection and a control method thereof, the circuit has a simple structure, is timely in protection, can accurately display the fault position and remove the fault, is convenient for problem troubleshooting, can accurately and timely display the position of the short-circuit fault in a circuit system, and is convenient for maintenance.
Therefore, the scheme of the invention adopts a novel circuit short circuit grading protection circuit, can effectively cut off a fault circuit in real time and display the fault position, and is convenient for finding problems and maintaining.
According to the scheme, only the circuit in the fault point area can be cut off, other normal circuits and loads are not affected, the short-circuit fault can be timely and accurately responded, the fault is cut off, the original state of the circuit is recovered, and more serious damage is avoided; and the influence on other circuits or loads can be reduced, so that other circuits can work normally.
The following describes an exemplary implementation process of the scheme of the present invention with reference to the examples shown in fig. 2 to 5.
In a related scheme, in a complex circuit system, one power supply is generally provided with only one unit protection circuit on the power supply side, and the targeted protection cannot be realized for all loads behind the power supply. The circuit structure provided by the scheme of the invention can realize point-to-point protection.
Fig. 2 is a schematic structural diagram of an embodiment of a minimum system level protection circuit. As shown in fig. 2, the minimum system hierarchy protection circuit includes: the switching power supply main circuit, the short-circuit protection unit main circuit (such as a short-circuit protection unit circuit) and the load. Switching power supply main circuit includes: the power supply comprises a switching power supply, a first power supply and a second power supply, wherein the first power supply is arranged on a first power line of the switching power supply, and the second power supply is arranged on a second power line of the switching power supply.
And a short-circuit protection unit circuit is arranged between the first power supply and the branch line on the first power line on the main line of the first power line. Branch line on first power cord includes: a first branch and a second branch arranged in parallel. And a short-circuit protection unit circuit is arranged on the first branch line between the short-circuit protection unit circuit on the main line of the first power line and the load on the first branch line. And a short-circuit protection unit circuit is arranged between the short-circuit protection unit circuit on the main line of the second power line and the load on the second branch line. And a short-circuit protection unit circuit is arranged on the second power supply line between the second power supply and the load on the second power supply line.
Therefore, each power main line and each branch line are provided with a protection circuit respectively corresponding to two fault conditions of power main line short circuit and load short circuit, so that when faults occur in different places, the protection circuit closest to the fault point can work in time, the fault point is cut off, and normal work of other circuits is not influenced.
Fig. 3 is a schematic structural diagram of an embodiment of a short-circuit protection unit. The example shown in fig. 3 is provided with a fault display function in addition to the short-circuit protection function to locate the location of the fault point.
As shown in fig. 3, the short-circuit protection unit circuit includes: the circuit comprises a power supply, a fault display and switch circuit, a load, a short-circuit detection circuit and a drive circuit. The power supply, the fault display and switch circuit, the load, the short-circuit detection circuit and the drive circuit are sequentially connected. And the driving circuit is also connected to the fault display and switch circuit.
When the circuit works normally, the switch circuit is in a closed state, and the current flows to the power supply → the fault display and the switch circuit → the load; when the load has short-circuit fault, the short-circuit detection circuit can detect the short-circuit signal, so that the short-circuit signal is transmitted to the drive circuit, and the drive circuit controls the fault display and the switch circuit in the switch circuit to be switched off and controls the fault display circuit in the fault display and switch circuit to display the fault signal.
Fig. 4 is a schematic structural diagram of another embodiment of the short-circuit protection unit. Fig. 4 can show a detailed internal structure diagram of the short-circuit protection unit circuit, which is completely different from other short-circuit protection circuits, and only a simple short-circuit protection unit circuit is composed of a resistor, a capacitor, a triode, a light-emitting diode and a comparator; the comparator detects the short-circuit signal, so that the triode is utilized to turn on and off the circuit, the used devices are few, the cost is low, and the comparator can be widely used in a complex circuit system.
As shown in fig. 3, the short-circuit protection unit circuit includes, in addition to the power supply and the load, main components including: the resistor R1, the resistor R2, the resistor R3, the resistor R4, the resistor R5, the resistor R6 and the resistor R7 are selected according to an actual circuit; the circuit comprises a light emitting diode LED1, an NPN triode Q1, an NPN triode Q2, a relay K1 (the contact of the relay K1 is a normally closed contact), a capacitor C1 and a comparator U1. Connection terminal of power main circuit, including: a V + terminal, a VCC terminal, and a VDD terminal. The V + terminal is connected to the anode of the light emitting diode LED1 through the resistor R1, the cathode of the light emitting diode LED1 is connected to the collector of the NPN transistor Q1, and the emitter of the NPN transistor Q1 is connected to the load. The base of NPN transistor Q1 is connected to the common terminal of resistor R2 and resistor R3. The V + terminal is also connected to the load through a resistor R2 and a resistor R3. And the V + terminal is also connected to a load through a normally closed contact of the relay K1. And the V + terminal is also connected to the collector of an NPN triode Q2 after passing through a coil of a relay K1. The emitter of the NPN triode Q2 is grounded, and the base of the NPN triode Q2 is grounded after passing through the capacitor C1. The base of the NPN transistor Q2 is also connected to the output terminal of the comparator U1 through a resistor R4. The power supply end of the comparator U1 is connected with the direct current power supply VCC, the grounding end of the comparator U1 is grounded, the non-inverting input end of the comparator U1 is connected with the direct current power supply VCC after passing through the resistor R6, and the inverting input end of the comparator U1 is connected with the load after passing through the resistor R5. The non-inverting input terminal of the comparator U1 is grounded through a resistor R7.
When the normal work is carried out: the normally closed contact of the relay K1 is closed, the current directly flows to the load from the power supply (i.e. the main power supply circuit), at this time, the voltage of the inverting input terminal of the comparator U1 is higher than the voltage of the non-inverting input terminal of the comparator U1, a low level is output to the base of the NPN triode Q2, the NPN triode Q2 is not conducted, the normally closed contact of the relay K1 is continuously kept in a closed state, the circuit normally works, at this time, the resistor R1, the resistor R2, the resistor R3, the light emitting diode LED1 and the NPN triode Q1 are short-circuited by the normally closed contact of the relay K1, so that the normally closed contact cannot work, and the.
When the load is short-circuited: the level of the inverting input terminal of the comparator U1 is pulled low, the voltage at the inverting input terminal of the comparator U1 is lower than that at the non-inverting input terminal of the comparator U1, and the comparator U1 outputs a high level. The NPN transistor Q2 is turned on, the normally closed contact of the relay K1 is opened, and current flows through the resistor R1, the light emitting diode LED1, the NPN transistor Q1, the resistor R2, and the resistor R3 to the load via the power supply (i.e., the main circuit of the power supply). The resistances of the resistor R1, the resistor R2 and the resistor R3 are as large as possible, so that the flowing current is small, the circuit loss can be reduced, and the effect of protecting a rear-stage circuit and a load is achieved.
Specifically, according to simulation test results, a current has a slight voltage drop after passing through the relay K1, if there is no NPN triode Q1, it is equivalent to connecting the light emitting diode LED1 and the resistor R1 in parallel at two ends of the relay, when the voltage drop at two ends of the relay is greater than 0.7V and the value of the resistor R1 is set to be small, the light emitting diode LED1 may be turned on by mistake, and when the NPN triode Q1 is added, since the voltage of the resistor R2 and the resistor R3 is divided (generally, the value of R3 is small and the value of R2 is large), only when the voltage difference between two ends of the relay K1 is large, the base voltage of the NPN triode Q1 can reach the on voltage, so that the NPN triode Q1 is turned on, so that the light emitting diode LED1 cannot be turned on by mistake when the circuit is not short-circuited, and the circuit is normally. The number of the setting paths can be determined according to the situation, and only one path can be set if the circuit does not consider the reliability of the circuit.
Fig. 5 is a schematic diagram of an embodiment of a minimum system level protection integrated circuit. The example shown in fig. 5 can show: the realization mode of the short-circuit grading protection function in a complex circuit system. Specifically, it is possible to specifically analyze how the circuit operates and how the hierarchical protection is implemented when different faults occur with respect to several fault points (e.g., a first fault point, a second fault point, and a third fault point). The short-circuit protection circuit in the related scheme can only protect against one fault and does not have a medium short-circuit grading protection function.
As shown in fig. 5, the minimum system protection circuit, the main power circuit, is connected to the first load through the first short-circuit protection unit circuit and the second short-circuit protection unit circuit. And the power supply main circuit is also connected to a second load through a third short-circuit protection unit circuit. The first fault is disposed at a rear side of the first short protection unit circuit, i.e., between the first short protection unit circuit and the second short protection unit circuit. The second fault is disposed at a rear side of the second short protection unit circuit, i.e., between the second short protection unit circuit and the first load. The third fault is disposed at a rear side of the third short protection unit circuit, i.e., between the third short protection unit circuit and the second load.
In the example shown in fig. 5, the minimum system stage protects the entire circuit, and two stages of short-circuit protection circuits are shared. Of course, in actual use, several more levels of protection can be added according to actual needs. The first fault and the third fault are preceded by primary protection, and secondary protection is performed between the first fault and the second fault.
When a fault occurs at the second fault, the normally closed contact of the relay K2 in the second short-circuit protection unit circuit is opened, the light emitting diode LED2 emits light to display the fault, the first fault and the third fault are still at high levels, the normally closed contact of the relay K1 in the first short-circuit protection unit circuit and the normally closed contact of the relay K3 in the third short-circuit protection unit circuit do not act, the light emitting diode LED1 in the first short-circuit protection unit circuit and the light emitting diode LED3 in the third short-circuit protection unit circuit are not conducted, namely, the front stage cannot be affected when the rear stage is short-circuited, and therefore the short-circuit point can be positioned at the second fault.
When the first fault position breaks down, the first fault rear-stage circuit is short-circuited and does not work, at the moment, the normally closed contact of the relay K1 in the first short-circuit protection unit circuit is disconnected, the light-emitting diode LED1 in the first short-circuit protection unit circuit emits light to display faults, other light-emitting diodes do not display, the fault point is positioned at the first fault position, and therefore the overall effect is achieved: the rear-stage short circuit does not affect the front-stage circuit, the short circuits of the same stage do not affect each other, the front-stage short circuit and the rear-stage short circuit do not work, and the light-emitting diode only can display at a fault position.
In the above embodiments, the light emitting diode may be replaced with other light emitting devices.
In the above embodiment, the NPN transistor may be replaced with a PNP transistor.
In the above embodiment, the relay can be replaced according to the actual power, and the relay, the IGBT, and the MOS transistor can be used for high power, and the MOS transistor and the triode can be used for low power, as shown in fig. 6 to 8.
As shown in fig. 6, when the load is short-circuited, the inverting terminal of the comparator U1 is at a low level, the comparator U1 outputs a high level, the transistor Q2 is turned on, the gate level of the IGBT1 is pulled low, the IGBT1 is turned off, and the LED1 emits light; during normal operation, the inverting terminal of the comparator U1 is at a high level, the comparator U1 outputs a low level, the triode Q2 is not conducted, the grid electrode of the IGBT1 is at a high level, the IGBT1 is not turned off, and the LED1 does not emit light.
As shown in fig. 7, when the load is short-circuited, the inverting terminal of the comparator U1 is at a low level, the comparator U1 outputs a high level, the transistor Q2 is turned on, the gate level of the MOFET1 is pulled low, the MOFET1 is turned off, and the LED1 emits light; in normal operation, the inverting terminal of the comparator U1 is at a high level, the comparator U1 outputs a low level, the triode Q2 is not conducted, the gate of the MOFET1 is at a high level, the MOFET1 is not turned off, and the LED1 does not emit light.
As shown in fig. 8, when the load is short-circuited, the positive phase terminal of the comparator U1 is at a low level, the comparator U1 outputs a low level, the transistor Q2 is not turned on, and the LED1 emits light; when the LED lamp normally operates, the positive phase end of the comparator U1 is at a high level, the comparator U1 outputs the high level, the triode Q2 is conducted, and the LED1 does not emit light.
In the above embodiment, the comparator may be replaced with an inverter or a triode circuit, as shown in fig. 9 and 10.
As shown in fig. 9, when the load is short-circuited, the inverter U1 outputs a low level, the transistor Q2 is turned on, the transistor K1 is turned off, and the LED1 emits light; when the LED lamp normally operates, the input of the inverter U1 is high level, the output of the inverter U1 is low level, the triode Q2 is not conducted, the K1 is not disconnected, and the LED1 does not emit light.
As shown in fig. 10, when the load is short-circuited, the base level of the transistor Q3 is low, the transistor Q3 is not turned on, the base level of the transistor Q2 is high, the transistor Q2 is turned on, the relay K1 is turned off, and the LED1 emits light; during normal operation, the base level of the triode Q3 is high level, the Q3 is conducted, the base level of the triode Q2 is low level, the Q2 is not conducted, the relay K1 is not disconnected, and the LED1 does not emit light.
Since the processing and functions implemented by the circuit system of this embodiment substantially correspond to the embodiments, principles, and examples of the apparatus shown in fig. 1, reference may be made to the related descriptions in the foregoing embodiments for details which are not described in detail in the description of this embodiment, and thus are not described herein again.
Through a large number of tests, the technical scheme of the invention is adopted, and the protection circuits are arranged on the main line and the branch line of each power supply and respectively correspond to two fault conditions of short circuit of the main line of the power supply and short circuit of the load, so that when faults occur in different places, the protection circuit closest to the fault point can work in time, the fault point is cut off, and the normal work of other circuits is not influenced.
According to the embodiment of the invention, a short-circuit protection method of the circuit system corresponding to the circuit system is also provided. The short-circuit protection method of the circuit system can comprise the following steps: the method comprises the steps that a short-circuit protection unit is arranged between a power supply and a load of a circuit system, and whether a power supply line of the power supply and the load have short-circuit faults or not is detected; and cutting off a portion in which a short-circuit fault occurs from the circuit system and displaying a position of the portion in which the short-circuit fault occurs in the circuit system, in the case where the short-circuit fault occurs in at least one of a power supply line of the power supply and the load.
Therefore, the short-circuit protection unit is arranged between the power supply and the load of the circuit system, so that the fault position can be accurately displayed, the fault can be removed, the problem troubleshooting is convenient, the position of the short-circuit fault in the circuit system can be accurately and timely displayed, and the maintenance is convenient.
Since the processes and functions implemented by the method of the present embodiment substantially correspond to the embodiments, principles and examples of the circuit system, reference may be made to the related descriptions in the embodiments without being detailed in the description of the present embodiment, which is not described herein again.
Through a large number of tests, the technical scheme of the embodiment is adopted, the short-circuit protection function and the fault display function are arranged in the short-circuit protection unit circuit, the position of a fault point can be positioned, only a circuit in a fault point area is cut off, other normal circuits and loads are not affected, the short-circuit fault can be timely and accurately responded, the fault is cut off, the original state of the circuit is recovered, and more serious damage is avoided; and the influence on other circuits or loads can be reduced, so that other circuits can work normally.
In summary, it is readily understood by those skilled in the art that the advantageous modes described above can be freely combined and superimposed without conflict.
The above description is only an example of the present invention, and is not intended to limit the present invention, and it is obvious to those skilled in the art that various modifications and variations can be made in the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the claims of the present invention.
Claims (11)
1. A short circuit protection device, comprising: a short-circuit protection unit; wherein the content of the first and second substances,
the short-circuit protection unit is arranged between a power supply and a load of a circuit system and is configured to detect whether a power supply line of the power supply and the load have short-circuit faults or not; and the number of the first and second groups,
and in the case that at least one of a power supply line of the power supply and the load has a short-circuit fault, cutting off a part having the short-circuit fault from the circuit system, and displaying the position of the part having the short-circuit fault in the circuit system.
2. The short-circuit protection device of claim 1, wherein the supply line of the power supply comprises: a main power supply line of the power supply and a branch power supply line of the power supply;
the number of the short-circuit protection units is more than one; one or more short-circuit protection units, comprising: the short-circuit protection unit is arranged on the power supply main line, and the short-circuit protection unit is arranged on the power supply branch line.
3. The short circuit protection device of claim 2, wherein the power supply comprises: a first sub power supply and a second sub power supply; the power supply main line comprises: a first main line and a second main line; the power supply branch line includes: a first branch line and a second branch line; the first sub power supply is connected to the first main line; the first branch line and the second branch line are two parallel branch lines led out from the first main line; the second sub power supply is connected to the second main line;
at least one short-circuit protection unit is arranged on the first main line and between the first sub-power supply and the first branch line; at least one short-circuit protection unit is arranged on the first branch line and the second branch line respectively;
and at least one short-circuit protection unit is arranged on the second main line.
4. The short-circuit protection device of claim 2, wherein the power main line comprises: a first main line and a second main line arranged in parallel;
at least one short-circuit protection unit is arranged on the first main line; and at least one short-circuit protection unit is arranged on the second main line.
5. The short-circuit protection device according to any one of claims 2 to 4, wherein one or more short-circuit protection units perform one or more short-circuit protection on a power supply line of the power supply and the load in a direction from the power supply to the load.
6. The short-circuit protection device according to any one of claims 1 to 4, wherein the short-circuit protection unit comprises: the short circuit detection module, the driving module and the fault display and switch unit are arranged on the circuit board; wherein the content of the first and second substances,
the short-circuit detection module is configured to detect whether a short-circuit fault occurs in a power supply line of the power supply and the load;
the driving module is configured to initiate a driving signal to the fault display and switch unit when at least one of a power supply line of the power supply and the load has a short-circuit fault;
the fault display and switch unit is configured to cut off a portion where a short-circuit fault occurs from the circuit system and display a position of the portion where the short-circuit fault occurs in the circuit system, in a case where the driving signal is received.
7. The short circuit protection device of claim 6, wherein the short circuit detection module comprises: the device comprises a sampling module, a comparison module and an output module; wherein the content of the first and second substances,
the short circuit detection module detects whether the power supply line of the power supply and the load have short circuit faults or not, and comprises:
the sampling module is configured to sample current voltages of a power supply line of the power supply and the load;
the comparison module is configured to compare the current voltage with a preset reference voltage so as to generate a short-circuit signal when the current voltage is lower than the reference voltage;
the output module is configured to output the short circuit signal to the driving module.
8. The short-circuit protection device of claim 6, wherein the drive module comprises: a first switch module;
the driving module initiates a driving signal to the fault display and switch unit, and the driving module comprises:
and under the condition of receiving the short-circuit signal, the first switch module is turned on to generate a driving signal.
9. The short-circuit protection device of claim 6, wherein the fault display and switch unit comprises: the display module comprises a first switch module and a display module; wherein the content of the first and second substances,
the fault display and switch unit cuts off a part with a short-circuit fault from the circuit system and displays the position of the part with the short-circuit fault in the circuit system, and comprises:
the second switch module is configured to disconnect the second switch module itself to cut off a power supply line of the power supply to a rear-stage circuit of the second switch module when the driving signal is received;
the display module is configured to enable the display module to be powered on and display under the condition that the driving signal is received, so that the position of a part of the circuit system where the short-circuit fault occurs is displayed in the circuit system.
10. A circuit system, comprising: a short circuit protection device as claimed in any one of claims 1 to 9.
11. A method of short-circuit protection of a circuit system according to claim 10, comprising:
the method comprises the steps that a short-circuit protection unit is arranged between a power supply and a load of a circuit system, and whether a power supply line of the power supply and the load have short-circuit faults or not is detected; and cutting off a portion in which a short-circuit fault occurs from the circuit system and displaying a position of the portion in which the short-circuit fault occurs in the circuit system, in the case where the short-circuit fault occurs in at least one of a power supply line of the power supply and the load.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011415068.8A CN112701654B (en) | 2020-12-04 | 2020-12-04 | Short-circuit protection device, circuit system and short-circuit protection method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011415068.8A CN112701654B (en) | 2020-12-04 | 2020-12-04 | Short-circuit protection device, circuit system and short-circuit protection method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112701654A true CN112701654A (en) | 2021-04-23 |
| CN112701654B CN112701654B (en) | 2023-02-28 |
Family
ID=75506310
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011415068.8A Active CN112701654B (en) | 2020-12-04 | 2020-12-04 | Short-circuit protection device, circuit system and short-circuit protection method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112701654B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113489132A (en) * | 2021-06-30 | 2021-10-08 | 广州极飞科技股份有限公司 | Power supply circuit and method |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB360412A (en) * | 1929-08-01 | 1931-10-30 | Ericsson Telefon Ab L M | Improvements in fire alarm systems |
| US4728898A (en) * | 1986-03-17 | 1988-03-01 | Staley Electric Co., Inc. | Method and apparatus for detecting and locating faults in an AC transmission line using two indicators |
| US5774321A (en) * | 1995-08-30 | 1998-06-30 | Samsung Electronics Co., Ltd. | Power supply circuit with load protection function |
| JPH11127065A (en) * | 1997-08-19 | 1999-05-11 | Harness Syst Tech Res Ltd | Short-circuit fault detection circuit |
| CN200973012Y (en) * | 2005-12-28 | 2007-11-07 | 武汉化工学院 | DC low voltage distributor |
| CN103457247A (en) * | 2013-08-09 | 2013-12-18 | 福州大学 | Multi-level full-range selective coordination and protection technology of low-voltage system |
| CN107472171A (en) * | 2017-07-04 | 2017-12-15 | 北汽福田汽车股份有限公司 | Power supply management device, method and vehicle |
| CN209805407U (en) * | 2019-03-19 | 2019-12-17 | 浙江大华技术股份有限公司 | Short-circuit protection circuit |
-
2020
- 2020-12-04 CN CN202011415068.8A patent/CN112701654B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB360412A (en) * | 1929-08-01 | 1931-10-30 | Ericsson Telefon Ab L M | Improvements in fire alarm systems |
| US4728898A (en) * | 1986-03-17 | 1988-03-01 | Staley Electric Co., Inc. | Method and apparatus for detecting and locating faults in an AC transmission line using two indicators |
| US5774321A (en) * | 1995-08-30 | 1998-06-30 | Samsung Electronics Co., Ltd. | Power supply circuit with load protection function |
| JPH11127065A (en) * | 1997-08-19 | 1999-05-11 | Harness Syst Tech Res Ltd | Short-circuit fault detection circuit |
| CN200973012Y (en) * | 2005-12-28 | 2007-11-07 | 武汉化工学院 | DC low voltage distributor |
| CN103457247A (en) * | 2013-08-09 | 2013-12-18 | 福州大学 | Multi-level full-range selective coordination and protection technology of low-voltage system |
| CN107472171A (en) * | 2017-07-04 | 2017-12-15 | 北汽福田汽车股份有限公司 | Power supply management device, method and vehicle |
| CN209805407U (en) * | 2019-03-19 | 2019-12-17 | 浙江大华技术股份有限公司 | Short-circuit protection circuit |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113489132A (en) * | 2021-06-30 | 2021-10-08 | 广州极飞科技股份有限公司 | Power supply circuit and method |
| CN113489132B (en) * | 2021-06-30 | 2024-03-01 | 广州极飞科技股份有限公司 | Power supply circuit and method |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112701654B (en) | 2023-02-28 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104297622B (en) | Detect the method and device of defects of display panel | |
| CN205080242U (en) | Power strip function test system | |
| KR20030070545A (en) | Fault diagnosis circuit for led display lamp | |
| EP3352372B1 (en) | Test device | |
| CN112701654B (en) | Short-circuit protection device, circuit system and short-circuit protection method thereof | |
| CN104078919A (en) | LED (Light-Emitting Diode) lamp and electronic breaker thereof | |
| CN110843529B (en) | High-voltage interlocking fault self-diagnosis circuit, control method and new energy automobile | |
| CN111864697A (en) | Overcurrent protection circuit and method and system for judging whether power supply is overhauled | |
| CN207992362U (en) | Detection circuit | |
| JP2011171547A (en) | Fault detection circuit of light emitting diode | |
| CN105657947B (en) | Circuit fault detecting apparatus, LED luminaire and light and/or sender unit | |
| CN111739458B (en) | Drive circuit and display drive chip | |
| CN107481678A (en) | Backlight drive current monitoring circuit, method and the display device of backlight module | |
| CN209841987U (en) | Detection circuit and detection device for anode and cathode of electrolytic capacitor | |
| WO2022156195A1 (en) | Test board | |
| JP2008098495A (en) | Led fault detection apparatus | |
| CN210742306U (en) | Short-circuit prevention makeup testing device | |
| CN112731825B (en) | Detection circuit, device and detection method thereof | |
| CN213633692U (en) | Conductivity detection circuit and detection device of TVS tube | |
| CN111812553A (en) | Detection circuit of alternating current input line and socket with detection circuit | |
| JPH05283748A (en) | Detecting circuit for failure of discontinuity and short circuit of light-emitting diode | |
| CN212323980U (en) | Drive circuit fault self-diagnosis frequency converter | |
| CN220209948U (en) | Multi-power-supply circuit with overvoltage and undervoltage protection | |
| CN211293154U (en) | Multi-way switch testing device | |
| CN220894393U (en) | Detection circuit applied to portable detection tool |
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 |