CN217824231U - Advanced response intrinsic safety protection circuit - Google Patents
Advanced response intrinsic safety protection circuit Download PDFInfo
- Publication number
- CN217824231U CN217824231U CN202220760680.7U CN202220760680U CN217824231U CN 217824231 U CN217824231 U CN 217824231U CN 202220760680 U CN202220760680 U CN 202220760680U CN 217824231 U CN217824231 U CN 217824231U
- Authority
- CN
- China
- Prior art keywords
- resistor
- operational amplifier
- circuit
- triode
- inverting input
- 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
Images
Landscapes
- Emergency Protection Circuit Devices (AREA)
Abstract
The utility model discloses an advance response intrinsic safety protection circuit is applied to colliery explosion-proof electric electronic circuit design field. The advanced response intrinsically safe protection circuit comprises: the protection circuit comprises an advanced protection control circuit, a fault voltage sudden change detection circuit, a fault current sudden change detection circuit and an overvoltage and overcurrent protection circuit; the advanced protection control circuit, the fault current sudden change detection circuit and the overvoltage and overcurrent protection circuit are sequentially connected; and the fault voltage sudden change detection circuit is respectively connected with the advanced protection control circuit and the overvoltage and overcurrent protection circuit. The utility model discloses a to fault voltage and fault current's quick response, solve among the current scheme because the detection to fault voltage and fault current lags behind and lead to the big problem of trouble discharge spark, improved the security performance of equipment greatly.
Description
Technical Field
The utility model relates to an explosion-proof electric electronic circuit design field in colliery especially relates to an advanced response intrinsic safety protection circuit.
Background
The underground coal mine is an environment with explosive dangers such as gas, coal dust and the like, and the intrinsic safety protection circuit is a circuit for ensuring that the intrinsic safety equipment achieves spark safety. According to explosion-proof requirements, the design of an intrinsic safety protection circuit relates to the limitation of capacitors and inductance energy storage elements of an intrinsic safety power supply and a power supply conversion circuit, and the selection of over-current and over-voltage protection circuit structures and device parameters, and in practical application, a capacitor with a certain capacitance value is necessary in order to obtain smaller output voltage ripples. An intrinsic safety protection circuit for an intrinsic safety power supply generally adopts a mode of detecting voltage drop ratio of two ends of a series sampling resistor to a set value to realize overcurrent judgment, adopts a mode of detecting voltage of a parallel sampling resistor to exceed the set value to realize overvoltage judgment, and further controls a switching tube to be turned off and output when a fault occurs; an intrinsic safety protection circuit for a power supply conversion circuit in intrinsic safety equipment usually limits the maximum input current by connecting a fuse in series at the input end of intrinsic safety power supply, and realizes overvoltage protection by combining a voltage regulator tube and a silicon controlled rectifier at the output end of the power supply conversion circuit in an overvoltage clamping manner.
With the progress and development of technologies, particularly the development of intelligent mines, intelligent mines and underground fifth-Generation Mobile Communication technology (5G) networks, new underground intrinsic safety equipment has more and more powerful functions and larger power consumption, the requirement on the output power of the intrinsic safety power supply is higher, higher requirements on the intrinsic safety protection mode and the response speed of the intrinsic safety equipment and the intrinsic safety power supply with higher power are provided, the fault protection scheme of the current intrinsic safety protection circuit needs to detect the over-limit current first and then trigger the protection, and the problems of fault protection lag and large discharge sparks exist.
SUMMERY OF THE UTILITY MODEL
The utility model aims at providing an advance response intrinsic safety protection circuit, the accessible is to fault voltage and fault current's quick response, solves among the current scheme because the problem that the detection to fault voltage and fault current lags behind and lead to the trouble to discharge the spark big, has improved the security performance of equipment greatly.
In order to achieve the above object, the utility model provides a following scheme:
a lead response intrinsically safe protection circuit, comprising: the device comprises an advanced protection control circuit, a fault voltage sudden change detection circuit, a fault current sudden change detection circuit and an overvoltage and overcurrent protection circuit;
the advanced protection control circuit, the fault current sudden change detection circuit and the overvoltage and overcurrent protection circuit are sequentially connected; and the fault voltage sudden change detection circuit is respectively connected with the advanced protection control circuit and the overvoltage and overcurrent protection circuit.
Optionally, the advance protection control circuit includes: the transistor comprises a P-channel field effect transistor, a first triode, a second triode and a third triode;
the collector of the first triode is connected with the base of the third triode;
the emitter of the first triode is respectively connected with the collector of the third triode, the base of the second triode, the source of the P-channel field effect transistor and the drain of the P-channel field effect transistor;
the base electrode of the first triode is respectively connected with the source electrode of the P-channel field effect transistor, the drain electrode of the P-channel field effect transistor, the base electrode of the second triode, the fault voltage sudden change detection circuit and the fault current sudden change detection circuit;
the grid electrode of the P-channel field effect transistor is connected with the collector electrode of the second triode;
and the emitting electrode of the second triode and the emitting electrode of the third triode are both grounded.
Optionally, the advance protection control circuit further includes: the circuit comprises a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor and a sixth resistor;
the collector of the first triode is connected with the base of the third triode through the first resistor;
the emitter of the first triode is connected with the collector of the third triode through the sixth resistor; the emitter of the first triode is connected with the base of the second triode through the fifth resistor; the emitting electrode of the first triode is connected with the drain electrode of the P-channel field effect transistor through the third resistor;
the base electrode of the first triode is connected with the source electrode of the P-channel field effect transistor through a second resistor;
and the emitter of the second triode is grounded through the fourth resistor.
Optionally, the advance protection control circuit further includes: a first capacitor; and the third resistor is connected with the drain electrode of the P-channel field effect transistor through the first capacitor.
Optionally, the fault voltage sudden change detection circuit includes a voltage regulator tube and a seventh resistor; the advanced protection control circuit, the voltage regulator tube, the seventh resistor and the overvoltage and overcurrent protection circuit are connected in sequence.
Optionally, the fault current sudden change detection circuit includes: a first operational amplifier, a second operational amplifier, a third operational amplifier, and a fourth operational amplifier;
the output end of the first operational amplifier is connected with the advanced protection control circuit;
the non-inverting input end of the first operational amplifier is connected with the overvoltage and overcurrent protection circuit; the non-inverting input end of the first operational amplifier is grounded;
the inverting input end of the first operational amplifier is respectively connected with the inverting input end of the second operational amplifier, the output end of the second operational amplifier and the output end of the third operational amplifier;
the output end of the second operational amplifier is respectively connected with the inverting input end of the third operational amplifier, the output end of the fourth operational amplifier and the non-inverting input end of the fourth operational amplifier;
the non-inverting input end of the second operational amplifier, the non-inverting input end of the third operational amplifier, the non-inverting input end of the fourth operational amplifier and the inverting input end of the fourth operational amplifier are all grounded.
Optionally, the fault current sudden change detection circuit further includes: the circuit comprises an eighth resistor, a ninth resistor, a tenth resistor, an eleventh resistor, a twelfth resistor, a thirteenth resistor, a fourteenth resistor, a fifteenth resistor, a sampling resistor, a voltage reference diode and a second capacitor;
the non-inverting input end of the first operational amplifier is connected with the eighth resistor; the eighth resistor is connected with the overvoltage and overcurrent protection circuit through the ninth resistor; the non-inverting input end of the first operational amplifier is grounded through a tenth resistor; the eighth resistor is connected with the tenth resistor through the voltage reference diode;
the inverting input end of the first operational amplifier is connected with the output end of the third operational amplifier through the eleventh resistor; the inverting input end of the first operational amplifier is connected with the output end of the second operational amplifier through the second capacitor;
the output end of the second operational amplifier is connected with the inverting input end of the third operational amplifier through the twelfth resistor; the inverting input end of the third operational amplifier is connected with the output end of the fourth operational amplifier through the thirteenth resistor; the output end of the fourth operational amplifier is connected with the non-inverting input end of the fourth operational amplifier through the fourteenth resistor;
the non-inverting input end of the fourth operational amplifier is grounded through the fifteenth resistor; and the inverting input end of the fourth operational amplifier is grounded through the sampling resistor.
Optionally, the ninth resistor is a sliding varistor.
Optionally, the overvoltage/overcurrent protection circuit includes one or more groups of overvoltage/overcurrent detection circuits; the fault voltage sudden change detection circuit and the fault current sudden change detection circuit are connected with the overvoltage and overcurrent detection circuit.
Optionally, the advanced response intrinsically safe protection circuit further comprises a fuse; and the power input end of the advanced protection control circuit is connected with the power supply through the fuse.
According to the utility model provides a concrete embodiment, the utility model discloses a following technological effect:
the embodiment of the utility model provides an advanced response intrinsic safety protection circuit, wherein an advanced protection control circuit, a fault current mutation detection circuit and an overvoltage and overcurrent protection circuit are sequentially connected; the fault voltage sudden change detection circuit is respectively connected with the advanced protection control circuit and the overvoltage and overcurrent protection circuit, the advanced response intrinsic safety protection circuit realizes the detection of fault voltage and fault current by arranging the fault current sudden change detection circuit and the fault voltage sudden change detection circuit on the basis of the traditional overvoltage and overcurrent protection circuit, and realizes the quick response to the fault voltage and the fault current by the advanced protection control circuit, thereby solving the problem of large fault discharge spark caused by the detection lag of the fault voltage and the fault current in the prior scheme and greatly improving the safety performance of equipment.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without inventive labor.
Fig. 1 is a schematic diagram of a leading response intrinsically safe protection circuit according to an embodiment of the present invention;
fig. 2 is a schematic diagram of an application principle of an advanced response intrinsically safe protection circuit provided by an embodiment of the present invention;
fig. 3 is a schematic circuit diagram of an advanced protection control circuit and a fault voltage sudden change detection circuit provided in an embodiment of the present invention;
fig. 4 is a schematic circuit diagram of a fault current sudden change detection circuit provided by an embodiment of the present invention;
fig. 5 is a schematic diagram of a spark discharge characteristic curve of a short-circuit fault of a capacitive circuit according to an embodiment of the present invention;
fig. 6 is a schematic circuit diagram of a set of over-voltage and over-current detection circuits provided by an embodiment of the present invention;
fig. 7 is a schematic circuit diagram of the advanced response intrinsically safe protection circuit of the present invention applied to an ib protection class intrinsically safe power circuit; fig. 7 (a) is a schematic circuit diagram of the advanced protection control circuit and the isolated AC-DC flyback conversion power supply; FIG. 7 (b) is a schematic circuit diagram of a fault voltage sudden change detection circuit, a fault current sudden change detection circuit and an overvoltage and overcurrent protection circuit;
fig. 8 is a schematic circuit diagram of the advanced response intrinsically safe protection circuit of the present invention applied to an ia protection class intrinsically safe consumer circuit; fig. 8 (a) is a schematic circuit diagram of the leading protection control circuit, the fault voltage sudden change detection circuit, and the DC step-down conversion circuit; fig. 8 (b) is a schematic circuit diagram of the fault current sudden change detection circuit and the overvoltage and overcurrent protection circuit.
Description of the symbols:
1-advanced protection control circuit; 2-fault voltage sudden change detection circuit; 3-fault current sudden change detection circuit; 4-overvoltage and overcurrent protection circuit; 5-an isolated AC-DC flyback conversion power supply; 6-DC step-down conversion circuit.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.
The utility model aims at providing an advance response intrinsic safety protection circuit, through the quick response to fault voltage and fault current, solve among the current scheme because the problem that leads to the trouble to discharge the spark big to fault voltage and fault current's detection lag, improved the security performance of equipment greatly.
In order to make the above objects, features and advantages of the present invention more comprehensible, the present invention is described in detail with reference to the accompanying drawings and the detailed description.
As shown in fig. 1-2, the advanced response intrinsically safe protection circuit of the present invention includes: the device comprises a leading protection control circuit 1, a fault voltage sudden change detection circuit 2, a fault current sudden change detection circuit 3 and an overvoltage and overcurrent protection circuit 4.
Specifically, the advanced protection control circuit 1, the fault current sudden change detection circuit 3 and the overvoltage and overcurrent protection circuit 4 are connected in sequence; the fault voltage sudden change detection circuit 2 is respectively connected with the advanced protection control circuit 1 and the overvoltage and overcurrent protection circuit 4. The fault voltage sudden change detection circuit 2 is used for detecting the voltage output by the overvoltage and overcurrent protection circuit 4 and transmitting a detected voltage fault signal (such as a voltage sudden change signal) to the advanced protection control circuit 1. The fault current sudden change detection circuit 3 is configured to detect a current output by the overvoltage/overcurrent protection circuit 4, and transmit a detected current fault signal (for example, a current sudden change signal) to the advance protection control circuit 1. The advanced protection control circuit 1 cuts off the power supply output when receiving a voltage fault signal and/or a current fault signal, so as to realize quick response and advanced protection of fault current sudden change and fault voltage sudden change.
Further, the advanced protection control circuit 1 includes: a P-channel field effect transistor T101, a first triode T102, a second triode T103, and a third triode T104.
Specifically, the collector of the first transistor T102 is connected to the base of the third transistor T104; an emitter of the first triode T102 is connected to a collector of the third triode T104, a base of the second triode T103, a source of the P-channel field effect transistor, and a drain of the P-channel field effect transistor, respectively; the base electrode of the first triode T102 is respectively connected with the source electrode of the P-channel field effect transistor, the drain electrode of the P-channel field effect transistor, the base electrode of the second triode T103, the fault voltage sudden change detection circuit 2 and the fault current sudden change detection circuit 3; the grid electrode of the P-channel field effect transistor is connected with the collector electrode of the second triode T103; the emitter of the second transistor T103 and the emitter of the third transistor T104 are both grounded.
Further, the advance protection control circuit 1 further includes: a first resistor R101, a second resistor R102, a third resistor R103, a fourth resistor R104, a fifth resistor R105, and a sixth resistor R106.
Specifically, the collector of the first transistor T102 is connected to the base of the third transistor T104 through the first resistor R101; the emitter of the first transistor T102 is connected to the collector of the third transistor T104 via the sixth resistor R106; an emitter of the first triode T102 is connected with a base of the second triode T103 through the fifth resistor R105; an emitter of the first triode T102 is connected with a drain of the P-channel field effect transistor through the third resistor R103; the base electrode of the first triode T102 is connected with the source electrode of the P-channel field effect transistor through a second resistor R102; the emitter of the second transistor T103 is grounded through the fourth resistor R104.
Further, the advanced protection control circuit 1 further includes: a first capacitor C101; the third resistor R103 is connected to the drain of the P-channel fet through the first capacitor C101.
Further, the fault voltage sudden change detection circuit 2 comprises a voltage regulator tube D201 and a seventh resistor R201; the advanced protection control circuit 1, the voltage regulator tube D201, the seventh resistor R201 and the overvoltage and overcurrent protection circuit 4 are connected in sequence.
Preferably, the voltage regulator tube D201 is respectively connected to the second resistor R102 of the leading protection control circuit 1 and the base of the first triode T102.
Further, the fault current sudden change detection circuit 3 includes: a first operational amplifier a301, a second operational amplifier a302, a third operational amplifier a303, and a fourth operational amplifier a304.
Specifically, the output end of the first operational amplifier a301 is connected with the leading protection control circuit 1; the non-inverting input end of the first operational amplifier A301 is connected with the overvoltage and overcurrent protection circuit 4; the non-inverting input end of the first operational amplifier A301 is grounded; the inverting input terminal of the first operational amplifier a301 is connected to the inverting input terminal of the second operational amplifier a302, the output terminal of the second operational amplifier a302, and the output terminal of the third operational amplifier a303, respectively; the output end of the second operational amplifier a302 is connected to the inverting input end of the third operational amplifier a303, the output end of the fourth operational amplifier a304, and the non-inverting input end of the fourth operational amplifier a304, respectively; the non-inverting input terminal of the second operational amplifier a302, the non-inverting input terminal of the third operational amplifier a303, the non-inverting input terminal of the fourth operational amplifier a304, and the inverting input terminal of the fourth operational amplifier a304 are all grounded.
Preferably, the output end of the first operational amplifier a301 is connected to the third resistor R103, the fifth resistor R105, the first capacitor C101, and the base of the second transistor T103 of the protection circuit 1.
Further, the fault current sudden change detection circuit 3 further includes: the circuit comprises an eighth resistor R301, a ninth resistor R302, a tenth resistor R303, an eleventh resistor R304, a twelfth resistor R305, a thirteenth resistor R306, a fourteenth resistor R307, a fifteenth resistor R308, a sampling resistor RS, a voltage reference diode N301 and a second capacitor C101.
Specifically, the non-inverting input terminal of the first operational amplifier a301 is connected to the eighth resistor R301; the eighth resistor R301 is connected to the overvoltage and overcurrent protection circuit 4 through the ninth resistor R302; the non-inverting input end of the first operational amplifier A301 is grounded through a tenth resistor R303; the eighth resistor R301 is connected to the tenth resistor R303 through the voltage reference diode N301; the inverting input terminal of the first operational amplifier a301 is connected to the output terminal of the third operational amplifier a303 through the eleventh resistor R304; the inverting input end of the first operational amplifier A301 is connected with the output end of the second operational amplifier A302 through the second capacitor C301; the output end of the second operational amplifier a302 is connected with the inverting input end of the third operational amplifier a303 through the twelfth resistor R305; the inverting input terminal of the third operational amplifier a303 is connected to the output terminal of the fourth operational amplifier a304 through the thirteenth resistor R306; the output end of the fourth operational amplifier a304 is connected to the non-inverting input end of the fourth operational amplifier a304 through the fourteenth resistor R307; the non-inverting input terminal of the fourth operational amplifier A304 is grounded through the fifteenth resistor R308; the inverting input terminal of the fourth operational amplifier a304 is grounded through the sampling resistor RS.
Further, the ninth resistor R302 is a sliding varistor.
Further, the overvoltage and overcurrent protection circuit 4 comprises one or more groups of overvoltage and overcurrent detection circuits; the fault voltage sudden change detection circuit 2 and the fault current sudden change detection circuit 3 are connected with the overvoltage and overcurrent detection circuit.
Further, the advanced response intrinsic safety protection circuit further comprises a fuse; and the power input end of the advanced protection control circuit 1 is connected with a power supply through the fuse.
As shown in fig. 3-4, in the advanced response intrinsically safe protection circuit of the present invention, the advanced protection control circuit 1 is used to implement the advanced protection of short-circuit fault according to the detection results of the fault voltage mutation detection circuit 2 and the fault current mutation detection circuit 3, and to implement the start-up anti-impact slow start function and the automatic restart function of the fault recovery circuit; the fault voltage sudden change detection circuit 2 is mainly used for monitoring voltage sudden change drop at an intrinsic safety output port of the overvoltage and overcurrent protection circuit 4 when faults such as overvoltage, short circuit to the ground and the like occur at the output port; the fault current sudden change detection circuit 3 is mainly used for monitoring the current sudden change increase of the intrinsic safety output port of the overvoltage and overcurrent protection circuit 4 caused by the short-circuit fault loop.
In the advance protection control circuit 1, at the moment of starting up, the P-channel fet T101, the first triode T102, the second triode T103, and the third triode T104 are turned off, the first capacitor C101 is charged through the third resistor R103, and simultaneously the base of the second triode T103 is gradually charged, then the second triode T103 is gradually turned on and controls the P-channel fet T101 to be gradually turned on, and finally the second triode T103 reaches a saturation state, the P-channel fet T101 is completely turned on, and the start-up is completed. The first capacitor C101 and the third resistor R103 form an RC timing circuit, so that a slow start function in a start-up process is realized.
When the output port of the overvoltage and overcurrent protection circuit 4 has overvoltage and short-circuit faults at the first moment, the output voltage drops suddenly, so that the differential pressure between the power supply input end and the output end is larger than the conduction value of the voltage stabilizing tube D201 in the fault voltage sudden change detection circuit 2, the base level of the first triode T102 in the advance protection control circuit 1 has current flowing, the state of the first triode T102 is changed from cut-off to conduction, the third triode T104 is conducted, the second triode T103 and the P-channel field effect tube T101 are cut off, and the circuit has no output.
When the advance protection control circuit 1 receives the CTR1 signal as a low level, the second triode T103 and the P-channel field effect transistor T101 are also cut off, and the circuit has no output.
When the P-channel field effect transistor T101 is turned off, the third resistor R103 charges the first capacitor C101, creating a condition for the next turn-on of the second triode T103, and when the short-circuit fault is not eliminated, the current flows into the ground through the third resistor R103, the fifth resistor R105, and the fourth resistor T104, the P-channel field effect transistor T101 is still turned off, and the circuit has no output; when the short-circuit fault is eliminated, the current flowing through the third resistor R103 flows into the base stage of the second triode T103, and the second triode T103 is gradually conducted, so that the P-channel field effect transistor T101 is gradually conducted, and the circuit output is recovered to normal.
The second P-channel fet T402 in fig. 3 is a protection operation element of the overvoltage/overcurrent protection circuit 4 in this embodiment, and is used to cut off the circuit output when overvoltage or overcurrent occurs.
In this embodiment, different slow start times can be set through matching of the third resistor R103 and the first capacitor C101, and the stabilivolt D201 with different voltage stabilization values is replaced to obtain different protection points.
In the fault current sudden change detection circuit 3, the fourth operational amplifier a304, the fourteenth resistor R307 and the fifteenth resistor R308 constitute a non-inverting amplifier circuit for amplifying the voltage signal obtained at the sampling resistor RS. The second operational amplifier a302, the third operational amplifier a303, the twelfth resistor R305, the thirteenth resistor R306 and the second capacitor C301 constitute a differential detection circuit, which is used to convert the amplified voltage signal into a differential signal, so as to obtain information representing current mutation. Then, a low-level control signal output of the current mutation information is formed by the first operational amplifier a301 (here, a301 is used as a comparator).
The voltage reference diode N301 provides a reference for setting an operation threshold value for the first operational amplifier a301 through matching of the ninth resistor R302 and the tenth resistor R303.
The power supply can be generally equivalent to a capacitive circuit, the short-circuit fault is the most main reason for generating spark discharge, and the capacitive energy storage element in the power supply is the main energy source for generating spark discharge when the short-circuit fault occurs. The present embodiment will explain four stages of the failed spark discharge by referring to fig. 5.
The I stage is a dielectric breakdown stage corresponding to t in FIG. 5 0 ～t 1 The stage is that initially, the output port is disconnected with the power ground, when a fault occurs, the output port and the power ground are continuously close to each other, when the distance of the corresponding voltage breakdown medium is reached, the medium is broken down, at the moment, the discharge current i (t) suddenly changes and rises sharply, and along with the approach of t 1 The time current change rate gradually becomes smaller; the discharge voltage u (t) drops rapidly.
Stage II is a spark generation stage, corresponding to t in FIG. 5 1 ～t 2 And a stage, in which the discharge current is reduced from the maximum value, and the discharge voltage is continuously reduced until the discharge voltage and the discharge current can generate spark discharge.
Stage III is a spark sustaining stage, corresponding to t in FIG. 5 2 ～t 3 And a stage in which both the discharge current and the discharge voltage are slowly decreased until the discharge voltage is decreased to the minimum sustain voltage.
The IV stage is a spark-off stage corresponding to t in FIG. 5 3 ～t 4 And in the stage, the fault contact is completely closed, the discharge voltage is reduced to zero, and the residual energy in the capacitor causes a small peak to appear in the discharge current.
The traditional intrinsic safety protection circuit triggers overcurrent protection when the voltage drop generated by the loop current flowing through the sampling resistor reaches a protection threshold value, and is hysteresis protection, and the protection response is t 1 ～t 3 Meanwhile, the current exceeds the protection threshold and enters a spark generation and maintenance stage, so that the current limiting of the fuse used in the intrinsic safety equipment is limited due to limited effect, the safety is unreliable if the current limiting is too large, and the requirement of necessary fluctuation tolerance in practical application cannot be met if the current limiting is too small; the utility model discloses based on the characteristic that the sudden change is fallen rapidly to the early electric current of short-circuit fault takes place for the power, the monitoring and the voltage that fall the sudden change and rise the sudden change through differential circuit to fault current realize leading protection, at t 0 ～t 1 The protection is triggered at the moment of initial sudden change of the current, sparks are extinguished at the stage of non-generation or germination, and the advanced response of fault protection is realized.
As shown in fig. 6, the present embodiment provides a schematic circuit diagram of a set of over-voltage and over-current detection circuits.
The sixteenth resistor R402 and the seventeenth resistor R403 form a voltage sampling circuit, the reference source N401 and the first comparator A401 form a voltage comparison circuit, when the output voltage in the circuit exceeds the set voltage, the divided voltage on the seventeenth resistor R403 is increased to exceed the reference source N401, and the comparator A401 outputs high level to control the third P-channel field effect transistor T401 to act to cut off the power supply output, so that overvoltage protection is realized.
The second resistor RS is a sampling resistor for current in the loop, and when the voltage at two ends of the sampling resistor exceeds the set voltage, the second comparator a402 outputs a high level to control the third P-channel fet T401 to operate to cut off the power supply output, thereby implementing overcurrent protection.
In addition, a voltage regulator tube and a thyristor are generally used as an overvoltage protection structure, and when an overvoltage fault occurs, the voltage regulator tube triggers the thyristor to act so as to clamp the output voltage to a very low potential, so that overvoltage protection is realized.
The overvoltage and overcurrent protection circuit 4 can be implemented in various forms, and fig. 6 is only used for explaining the principle of the overvoltage and overcurrent protection circuit, and is not taken as an example. Can be adjusted according to actual needs.
As shown in fig. 7, the present embodiment provides a circuit schematic diagram of applying the advanced response intrinsically safe protection circuit to an ib protection level intrinsically safe power circuit, and converts an AC input into an isolated DC output through an isolated flyback AC-DC converter 5, wherein the overvoltage and overcurrent protection circuit 4 adopts a dual overvoltage and overcurrent protection circuit specifically implemented by taking a voltage limiting and current limiting chip LT4363 as a core.
As shown in fig. 8, the present embodiment provides a circuit schematic diagram of applying a leading response intrinsically safe protection circuit to an ia protection level intrinsically safe electrical device circuit. The DC step-down conversion circuit 6 is arranged between the advanced protection control circuit 1 and the fault current sudden change detection circuit 3, so that the advanced response intrinsic safety protection suitable for the ia protection level intrinsic safety electric equipment circuit is realized.
In the above description, the intrinsic safety protection circuits applied to ia and ib with different protection levels are only embodied in the protection circuits according to the requirements of the parallel connection quantity and the generality, which is convenient for the understanding of those skilled in the art, and are not taken as an example. Can be adjusted according to actual needs.
The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other.
The principle and the implementation of the present invention are explained herein by using specific examples, and the above description of the embodiments is only used to help understand the method and the core idea of the present invention; meanwhile, for the general technical personnel in the field, according to the idea of the present invention, there are changes in the concrete implementation and the application scope. In summary, the content of the present specification should not be construed as a limitation of the present invention.
Claims (10)
1. A lead response intrinsically safe protection circuit, comprising: the protection circuit comprises an advanced protection control circuit, a fault voltage sudden change detection circuit, a fault current sudden change detection circuit and an overvoltage and overcurrent protection circuit;
the advanced protection control circuit, the fault current sudden change detection circuit and the overvoltage and overcurrent protection circuit are sequentially connected; and the fault voltage sudden change detection circuit is respectively connected with the advanced protection control circuit and the overvoltage and overcurrent protection circuit.
2. The lead response intrinsic safety protection circuit of claim 1, wherein the lead protection control circuit comprises: the transistor comprises a P-channel field effect transistor, a first triode, a second triode and a third triode;
the collector of the first triode is connected with the base of the third triode;
the emitter of the first triode is respectively connected with the collector of the third triode, the base of the second triode, the source of the P-channel field effect transistor and the drain of the P-channel field effect transistor;
the base electrode of the first triode is respectively connected with the source electrode of the P-channel field effect transistor, the drain electrode of the P-channel field effect transistor, the base electrode of the second triode, the fault voltage sudden change detection circuit and the fault current sudden change detection circuit;
the grid electrode of the P-channel field effect transistor is connected with the collector electrode of the second triode;
and the emitting electrode of the second triode and the emitting electrode of the third triode are both grounded.
3. The lead-response intrinsically-safe protection circuit of claim 2, wherein the lead-protection control circuit further comprises: the circuit comprises a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor and a sixth resistor;
the collector electrode of the first triode is connected with the base electrode of the third triode through the first resistor;
the emitter of the first triode is connected with the collector of the third triode through the sixth resistor; the emitter of the first triode is connected with the base of the second triode through the fifth resistor; the emitting electrode of the first triode is connected with the drain electrode of the P-channel field effect transistor through the third resistor;
the base electrode of the first triode is connected with the source electrode of the P-channel field effect transistor through a second resistor;
and the emitter of the second triode is grounded through the fourth resistor.
4. The lead-response intrinsically-safe protection circuit of claim 3, wherein the lead-protection control circuit further comprises: a first capacitor; and the third resistor is connected with the drain electrode of the P-channel field effect transistor through the first capacitor.
5. The lead response intrinsic safety protection circuit of claim 1, wherein the fault voltage discontinuity detection circuit comprises a regulator tube and a seventh resistor; the advanced protection control circuit, the voltage regulator tube, the seventh resistor and the overvoltage and overcurrent protection circuit are connected in sequence.
6. The lead-response intrinsically-safe protection circuit of claim 1, wherein the fault-current sudden-change detection circuit comprises: a first operational amplifier, a second operational amplifier, a third operational amplifier, and a fourth operational amplifier;
the output end of the first operational amplifier is connected with the advanced protection control circuit;
the non-inverting input end of the first operational amplifier is connected with the overvoltage and overcurrent protection circuit; the non-inverting input end of the first operational amplifier is grounded;
the inverting input end of the first operational amplifier is respectively connected with the inverting input end of the second operational amplifier, the output end of the second operational amplifier and the output end of the third operational amplifier;
the output end of the second operational amplifier is respectively connected with the inverting input end of the third operational amplifier, the output end of the fourth operational amplifier and the non-inverting input end of the fourth operational amplifier;
the non-inverting input end of the second operational amplifier, the non-inverting input end of the third operational amplifier, the non-inverting input end of the fourth operational amplifier and the inverting input end of the fourth operational amplifier are all grounded.
7. The lead-response intrinsically-safe protection circuit of claim 6, wherein the fault-current sudden-change detection circuit further comprises: the circuit comprises an eighth resistor, a ninth resistor, a tenth resistor, an eleventh resistor, a twelfth resistor, a thirteenth resistor, a fourteenth resistor, a fifteenth resistor, a sampling resistor, a voltage reference diode and a second capacitor;
the non-inverting input end of the first operational amplifier is connected with the eighth resistor; the eighth resistor is connected with the overvoltage and overcurrent protection circuit through the ninth resistor; the non-inverting input end of the first operational amplifier is grounded through a tenth resistor; the eighth resistor is connected with the tenth resistor through the voltage reference diode;
the inverting input end of the first operational amplifier is connected with the output end of the third operational amplifier through the eleventh resistor; the inverting input end of the first operational amplifier is connected with the output end of the second operational amplifier through the second capacitor;
the output end of the second operational amplifier is connected with the inverting input end of the third operational amplifier through the twelfth resistor; the inverting input end of the third operational amplifier is connected with the output end of the fourth operational amplifier through the thirteenth resistor; the output end of the fourth operational amplifier is connected with the non-inverting input end of the fourth operational amplifier through the fourteenth resistor;
the non-inverting input end of the fourth operational amplifier is grounded through the fifteenth resistor; and the inverting input end of the fourth operational amplifier is grounded through the sampling resistor.
8. The lead response intrinsic safety protection circuit of claim 7, wherein the ninth resistor is a sliding varistor.
9. The lead response intrinsic safety protection circuit of claim 1, wherein the over-voltage and over-current protection circuit comprises one or more sets of over-voltage and over-current detection circuits; the fault voltage sudden change detection circuit and the fault current sudden change detection circuit are connected with the overvoltage and overcurrent detection circuit.
10. The lead response intrinsically safe protection circuit of claim 1, further comprising a fuse; and the power input end of the advanced protection control circuit is connected with the power supply through the fuse.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202220760680.7U CN217824231U (en) | 2022-04-02 | 2022-04-02 | Advanced response intrinsic safety protection circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202220760680.7U CN217824231U (en) | 2022-04-02 | 2022-04-02 | Advanced response intrinsic safety protection circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN217824231U true CN217824231U (en) | 2022-11-15 |
Family
ID=83978950
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202220760680.7U Active CN217824231U (en) | 2022-04-02 | 2022-04-02 | Advanced response intrinsic safety protection circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN217824231U (en) |
-
2022
- 2022-04-02 CN CN202220760680.7U patent/CN217824231U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN201188584Y (en) | Large-capacity essential safety power supply for coal mine | |
| CN202634297U (en) | Novel 18V mine explosion suppression and intrinsic safety power supply based on dual-redundancy protection circuit | |
| CN103681039B (en) | A kind of high-voltage direct-current breaker topology | |
| CN103872658B (en) | Multifunction self-resetting formula is crossed, under-voltage protector | |
| CN104218558B (en) | Anti-surging high tension protection circuit | |
| CN109327011A (en) | Overvoltage protection device | |
| CN103887787A (en) | Arc extinguishing method of intrinsically safe inductive circuit | |
| CN103036196A (en) | Device for overvoltage protection and method thereof | |
| CN104218531A (en) | Short circuit protecting circuit and method | |
| CN106024497B (en) | Auxiliary circuit for high-short-circuit turn-off direct-current circuit breaker and control method thereof | |
| CN109962462B (en) | Direct current electric wire netting two-way current blocking circuit based on series switch | |
| CN217824231U (en) | Advanced response intrinsic safety protection circuit | |
| CN105684313A (en) | Information converter power supply circuit, system, and power supply method | |
| CN104768258A (en) | Constant current driven LED over-voltage and over-current protection circuit | |
| CN217824724U (en) | Intrinsic safety power circuit with fault recovery self-starting function | |
| CN202679748U (en) | LED driving power supply circuit | |
| CN202564933U (en) | Power supply device | |
| CN204068210U (en) | Short-circuit protection circuit | |
| CN101771260A (en) | Mine intrinsic safety electric source interception self-recovery protection device | |
| CN105706348A (en) | Cable node unit power supply circuit, system, and power control method | |
| CN114977089A (en) | Advanced response intrinsic safety protection circuit | |
| CN103475191A (en) | Control circuit of switching power supply | |
| CN201341015Y (en) | Overvoltage protector for self excited generator | |
| CN111064172A (en) | Protection circuit and variable pitch system | |
| CN102938559B (en) | Electric spark restriction device and method of intrinsically-safe power supply |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |