Intrinsically safe power supply protection circuit and electrical equipment

Abstract

The utility model relates to the field of intrinsically safe power supply protection circuits, and discloses an intrinsically safe power supply protection circuit and electrical equipment. The circuit comprises a preceding-stage current blocking module, the first end of which is used for being connected with a power supply; the first end of the power conversion module is connected with the second end of the preceding-stage current blocking module; the first end of the overload protection module is connected with the second end of the power supply conversion module, and the overload protection module is used for blocking the connection between the power supply conversion module and the post-stage voltage stabilization module when the circuit is in an overvoltage or overcurrent state; the first end of the post-stage voltage stabilization module is connected with the second end of the overload protection module; the second end of the post-stage voltage stabilization module is used for being connected with a voltage output end. According to the embodiment of the invention, through the combined action of the overload protection module and the post-stage voltage stabilization module, overcurrent and overvoltage protection of the circuit is realized, and then the post-stage circuit and external electric equipment are prevented from being damaged by overvoltage or overcurrent.

Description

Technical Field

[0001] The present application relates to the field of intrinsically safe protection circuits, and in particular to an intrinsically safe power supply protection circuit and electrical equipment. Background Art

[0002] For intrinsically safe circuits, the stable working state of the equipment is the guarantee to ensure that no production accidents will occur under special circumstances. When the voltage or current suddenly changes due to some reason, the voltage or current rises sharply in a very short time, which can easily damage the circuit board, thereby causing the equipment to generate a lot of heat. In some special working environments (such as high concentrations of flammable, explosive gases and dust working environments), the damage to the equipment may bring immeasurable life and property safety. Therefore, how to achieve the protection of intrinsically safe power circuits to ensure that the equipment or circuit maintains a stable working state is an urgent problem to be solved. Utility Model Content

[0003] In view of this, in order to solve the problems existing in the prior art, the utility model provides an intrinsically safe power supply protection circuit and electrical equipment.

[0004] In a first aspect, the utility model provides an intrinsically safe power supply protection circuit, comprising:

[0005] A front-stage current blocking module, wherein a first end of the front-stage current blocking module is used to connect to a power source;

[0006] A power conversion module, a first end of which is connected to a second end of the front-stage current blocking module;

[0007] An overload protection module, a first end of the overload protection module is connected to a second end of the power conversion module;

[0008] A post-stage voltage stabilizing module, wherein a first end of the post-stage voltage stabilizing module is connected to a second end of the overload protection module; and a second end of the post-stage voltage stabilizing module is used to connect to a voltage output end;

[0009] Wherein, the overload protection module is used to block the connection between the power conversion module and the subsequent voltage stabilization module when the intrinsically safe power protection circuit is in an overvoltage or overcurrent state.

[0010] In an optional embodiment, the overload protection module is a fuse group; the fuse group includes at least one fuse, and the conductive parts at both ends of each fuse are correspondingly connected to the power conversion module and the post-stage voltage stabilization module;

[0011] The fuse group is used to fuse when the current value output by the power conversion module is greater than a preset current threshold, so as to disconnect the connection between the power conversion module and the subsequent voltage stabilization module.

[0012] In an optional embodiment, each of the fuses is disposed in a main body of a fuse holder, and conductive parts are disposed at both ends of the fuse holder, and the conductive parts are respectively connected to input and output terminals of the power conversion module and the subsequent voltage stabilization module;

[0013] The fuse holder comprises conductive abutting portions respectively arranged at two ends of each of the fuses, and each of the conductive abutting portions is electrically connected to a corresponding fuse and abuts against the conductive portion.

[0014] In an optional embodiment, the conductive abutting portion is disposed on the lower surface of the main body, and each of the conductive abutting portions is connected to a conductive portion of a corresponding fuse.

[0015] In an optional embodiment, the front-stage current blocking module includes a first diode to an Nth diode connected in series in the same polarity direction, the anode of the first diode is used to connect to the power supply, and the cathode of the Nth diode is connected to the power conversion module; N≥1.

[0016] In an optional implementation, the post-stage voltage stabilization module includes a plurality of voltage stabilization diodes connected in parallel; wherein one end of each of the voltage stabilization diodes is respectively connected to the second end of the overload protection module, and the other end of each of the voltage stabilization diodes is grounded.

[0017] In an optional embodiment, the power conversion module is a DC-DC conversion module; the DC input end of the DC-DC conversion module is connected to the front-stage current blocking module, and the DC output end of the DC-DC conversion module is connected to the post-stage voltage stabilization module, which is used to convert the DC input voltage from the power supply received by the front-stage current blocking module into a DC output voltage, wherein the voltage value of the DC output voltage is less than the voltage value of the DC input voltage.

[0018] In an optional implementation, the power conversion module includes a power conversion chip and its peripheral circuits.

[0019] In a second aspect, the utility model provides an electrical device, comprising the intrinsically safe power supply protection circuit as mentioned above.

[0020] In an optional embodiment, the electrical equipment is an intrinsically safe switching device for mining.

[0021] The embodiments of the present application have the following beneficial effects:

[0022] The embodiment of the present application provides an intrinsically safe power supply protection circuit, which includes: a front-stage current blocking module, the first end of the front-stage current blocking module is used to connect to the power supply; a power conversion module, the first end of the power conversion module is connected to the second end of the front-stage current blocking module; an overload protection module, the first end of the overload protection module is connected to the second end of the power conversion module, and the overload protection module is used to block the connection between the power conversion module and the rear-stage voltage stabilizing module when the intrinsically safe power supply protection circuit is in an overvoltage or overcurrent state; a rear-stage voltage stabilizing module, the first end of the rear-stage voltage stabilizing module is connected to the second end of the overload protection module; the second end of the rear-stage voltage stabilizing module is used to connect to the voltage output end. The embodiment of the present application blocks the connection between the power conversion module and the rear-stage voltage stabilizing module when the circuit is in an overcurrent state, thereby realizing overcurrent protection of the circuit, and triggers the voltage stabilizing diode to turn on when the circuit is in an overvoltage state through the rear-stage voltage stabilizing module, thereby guiding the excess voltage to the ground, realizing overvoltage protection of the circuit, thereby preventing the rear-stage circuit and the external electrical equipment from being damaged by overvoltage or overcurrent. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solution of the present application, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present application and should not be regarded as limiting the scope of protection of the present application. In each of the drawings, similar components are numbered similarly.

[0024] Figure 1 A first structural schematic diagram of an intrinsically safe power supply protection circuit in an embodiment of the utility model is shown;

[0025] Figure 2 A second structural schematic diagram of an intrinsically safe power supply protection circuit in an embodiment of the utility model is shown;

[0026] Figure 3 A third structural schematic diagram of the intrinsically safe power supply protection circuit in an embodiment of the utility model is shown. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments.

[0028] The components of the embodiments of the present application generally described and shown in the drawings herein may be arranged and designed in various configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application.

[0029] Hereinafter, the terms "including", "having" and their cognates, which may be used in various embodiments of the present application, are intended only to indicate specific features, numbers, steps, operations, elements, components, or combinations of the foregoing items, and should not be understood as first excluding the existence of one or more other features, numbers, steps, operations, elements, components, or combinations of the foregoing items or adding the possibility of one or more features, numbers, steps, operations, elements, components, or combinations of the foregoing items.

[0030] Furthermore, the terms “first”, “second”, “third”, etc. are merely used for distinguishing descriptions and are not to be understood as indicating or implying relative importance.

[0031] Unless otherwise defined, all terms (including technical terms and scientific terms) used herein have the same meanings as those generally understood by those skilled in the art to which the various embodiments of the present application belong. The terms (such as those defined in generally used dictionaries) will be interpreted as having the same meanings as the contextual meanings in the relevant technical field and will not be interpreted as having idealized meanings or overly formal meanings unless clearly defined in the various embodiments of the present application.

[0032] In mining or some special environments, electrical equipment must have a stable voltage input to ensure safe operation. For example, in order to ensure that electrical equipment can operate normally in an operating scenario with high concentration of explosive gas and to protect the safety of the operating scenario in case of equipment failure, it is necessary to design a protection circuit that can effectively provide safety protection in case of electrical equipment failure, so as to avoid explosion in the surrounding environment caused by equipment failure, and to ensure that the electrical equipment can effectively and quickly protect the power circuit in case of circuit failure.

[0033] Based on this, the utility model provides an intrinsically safe power supply protection circuit, which realizes overcurrent protection and overvoltage protection of the circuit through the combined action of the overload protection module 300 and the post-stage voltage stabilization module 400, thereby preventing the post-stage circuit and the external electrical equipment from being damaged by overvoltage or overcurrent, so as to ensure that the intrinsically safe power supply protection circuit can effectively and quickly protect the power supply circuit when the circuit fails. Among them, the intrinsically safe power supply protection circuit can be applied to electrical equipment, so that the electrical equipment can be applied to special scenarios such as mining scenarios where circuit protection safety is more important, and effectively realize the rapid protection of the power supply circuit.

[0034] like Figure 1 As shown, the intrinsically safe power protection circuit includes a front-stage current blocking module 100, a power conversion module 200, an overload protection module 300 and a rear-stage voltage stabilization module 400 which are connected in sequence.

[0035] Exemplarily, the first end of the front-stage current blocking module 100 is used to connect to the power supply, that is, the front-stage current blocking module 100 is connected to the output end of the power supply to connect to the power supply voltage; the first end of the power conversion module 200 is connected to the second end of the front-stage current blocking module 100; the first end of the overload protection module 300 is connected to the second end of the power conversion module 200, and the overload protection module 300 is used to block the connection between the power conversion module 200 and the post-stage voltage stabilizing module 400 when the intrinsically safe power supply protection circuit is in an overvoltage or overcurrent state; the first end of the post-stage voltage stabilizing module 400 is connected to the second end of the overload protection module 300; the second end of the post-stage voltage stabilizing module 400 is used to connect to the voltage output end.

[0036] It can be understood that the front-stage current blocking module 100 of the present embodiment inputs the power supply voltage to the power conversion module 200 for power conversion processing, and then outputs it to the electrical equipment through the overload protection module 300 and the rear-stage voltage stabilizing module 400 to provide the electrical equipment with a power supply voltage of a suitable voltage value. In this process, secondary protection of the circuit is implemented through the overload protection unit to avoid inputting a large power supply voltage to the rear-stage voltage stabilizing module 400 and the electrical equipment, which may cause overvoltage or overcurrent damage to the rear-stage voltage stabilizing module 400 and the electrical equipment.

[0037] In this embodiment, the front-stage current blocking module 100 and the power conversion module 200 can be used as the front-stage circuit of the intrinsically safe power protection circuit, and the overload protection module 300 and the rear-stage voltage stabilizing module 400 can be used as the rear-stage circuit of the intrinsically safe power protection circuit. If the front-stage voltage output by the front-stage circuit is directly injected into the rear-stage circuit, causing the rear-stage circuit to be overvoltage or overcurrent, the overload protection module 300 and the rear-stage voltage stabilizing module 400 will be triggered to perform overvoltage protection or overcurrent protection on the rear-stage circuit, thereby ensuring that the rear-stage circuit can not be damaged by the overvoltage or overcurrent of the front-stage circuit, achieving the purpose of efficiently controlling the on and off of the power circuit, and playing a secondary protection role.

[0038] See also Figure 2 As shown, in one embodiment, the front-stage current blocking module 100 includes a first diode (ie, D1) to an Nth diode (ie, D N ); wherein the anode of the first diode is used to access the power supply (ie, VCC), and the cathode of the Nth diode is connected to the power conversion module 200; wherein N≥1, and N is an integer.

[0039] Specifically, the anode of the first diode is used to connect to the power supply, and the cathode of the Nth diode is connected to the input end of the power conversion module 200, wherein the anodes of the (N-2) diodes between the first diode and the Nth diode are respectively connected to the cathode of the previous diode, and the cathodes of the (N-2) diodes between the first diode and the Nth diode are respectively connected to the anode of the latter diode. The number of diodes included in the front-stage current blocking module 100 can be set according to actual needs and is not limited here.

[0040] In this embodiment, the front-stage current blocking module 100 can prevent current backflow for the intrinsically safe power supply protection circuit. It prevents current backflow caused by sudden power failure through the unidirectional conduction characteristics of the diode, thereby achieving safety protection of the front-stage circuit.

[0041] In one embodiment, the overload protection module 300 is a short-circuit device, for example, the overload protection module 300 can be a fuse group (i.e., F); wherein the fuse group includes at least one fuse, and the conductive parts at both ends of each fuse are correspondingly connected to the power conversion module 200 and the subsequent voltage stabilizing module 400; the fuse group is used to fuse when the current value output by the power conversion module 200 is greater than a preset current threshold, so as to disconnect the connection between the power conversion module 200 and the subsequent voltage stabilizing module 400. The specific value of the preset current threshold and the number of fuses can be set according to actual needs and are not limited here.

[0042] It can be understood that this embodiment implements circuit protection through a short-circuit device such as a fuse. When the power conversion module 200 fails, causing the voltage or current connected to the fuse to exceed the specified range, the power supply can be quickly short-circuited to avoid overvoltage or overcurrent damage to the subsequent circuit.

[0043] In some examples, each fuse is disposed in the main body of the fuse holder, and conductive parts are disposed at both ends of the fuse holder, respectively, and the conductive parts are connected to the input and output terminals of the power conversion module 200 and the post-stage voltage stabilization module 400, respectively; the fuse holder includes conductive abutment parts disposed at both ends of each fuse, and each conductive abutment part is electrically connected to the corresponding fuse and abuts against the conductive part. Among them, a fuse holder can be used to carry a single fuse or a fuse group, and the specific number of fuses carried can be set according to actual needs, and this embodiment does not limit this. In addition, the specific setting of the fuse holder can be set according to actual needs. This embodiment only lists and illustrates one example, and other structural types of the fuse holder are not limited here.

[0044] Optionally, the conductive abutment portion of the fuse holder is disposed on the lower surface of the main body, and the conductive abutment portions provided at both ends of each fuse are connected to the conductive portions at both ends of the corresponding fuse.

[0045] That is, the conductive part at each end of each fuse is respectively connected to the conductive abutment part set up at each end of the fuse. The conductive abutment part is then connected to the conductive parts at both ends of the fuse holder, so that the fuse is electrically connected to the fuse holder through the conductive abutment part and the conductive part. The conductive part of the fuse holder is respectively connected to the input and output terminals of the power conversion module 200 and the subsequent voltage stabilizing module 400, and then the fuse can be electrically connected to the input and output terminals of the power conversion module 200 and the subsequent voltage stabilizing module 400 through the fuse holder.

[0046] In one embodiment, the power conversion module 200 may be a DC-DC conversion module; wherein the DC input end of the DC-DC conversion module is connected to the front-stage current blocking module 100, and the DC output end of the DC-DC conversion module is connected to the rear-stage voltage stabilization module 400, for converting the DC input voltage from the power source received by the front-stage current blocking module 100 into a DC output voltage, wherein the voltage value of the DC output voltage is less than the voltage value of the DC input voltage. That is, the power conversion module 200 converts the connected power supply voltage into a power supply voltage of a corresponding voltage value suitable for powering an external electrical device.

[0047] Optionally, the power conversion module 200 may also include a power conversion chip and its peripheral circuits, or an integrated circuit composed of other discrete devices; wherein the specific circuit configuration of the power conversion module 200 may be configured according to actual needs, and this embodiment does not limit this.

[0048] In some examples, the post-stage voltage stabilization module 400 includes a plurality of voltage stabilizing diodes (ie, voltage stabilizing diodes D N+1 ~D M , N, M≥1, N, M are integers); wherein one end of each voltage regulator diode is respectively connected to the second end of the overload protection module 300, and the other end of each voltage regulator diode is grounded. That is, the post-stage voltage regulator module 400 can realize overvoltage protection of the circuit through the set voltage regulator diode, that is, according to the overvoltage and undervoltage maintenance function of the voltage regulator diode itself, as well as the faster response speed and low resistance characteristics, once the access voltage exceeds the breakdown voltage of the voltage regulator diode itself, the voltage regulator diode will start to conduct, and guide the excess voltage to the ground, protecting other components from the influence of overvoltage, and realizing overvoltage protection of the circuit. Among them, the number of voltage regulator diodes included in the post-stage voltage regulator module 400 can be set according to actual needs, and this embodiment does not limit this.

[0049] For example, Figure 3 As shown, the front-stage current blocking module 100 includes two diodes, namely, a first diode D1 and a second diode D2; the overload protection module 300 includes a fuse F1; the rear-stage voltage stabilizing module 400 includes two voltage stabilizing diodes, namely, a first voltage stabilizing diode D3 and a second voltage stabilizing diode D4. Among them, the anode of the first diode D1 is used to access the power supply, and the cathode of the first diode D1 is connected to the anode of the second diode; the cathode of the second diode D2 is connected to one end of the power conversion module 200; the other end of the power conversion module 200 is connected to the conductive part of one end of the fuse F1; the conductive part of the other end of the fuse F1 is respectively connected to one end of the first voltage stabilizing diode D3 and the second voltage stabilizing diode D4, and is used to connect the voltage output end (i.e., Vout); the other ends of the first voltage stabilizing diode D3 and the second voltage stabilizing diode D4 are both grounded.

[0050] It is worth noting that, in this embodiment, the power of the voltage regulator diode used in the post-stage voltage regulator module 400 can be specifically calculated according to the working voltage error value of the voltage regulator diode, the fuse parameters and the maximum fuse factor of the fuse, and the power supply voltage value. That is, the power of the voltage regulator diode is adjusted and controlled according to the working voltage error value of the voltage regulator diode, the fuse parameters and the maximum fuse factor of the fuse, and the power supply voltage value, and then the corresponding type of voltage regulator diode is selected according to the power of the voltage regulator diode obtained by calculation.

[0051] For example, if the power supply voltage to be protected is 5V, the working voltage of the Zener diode is 5V, and then the product of the fuse parameter and the maximum fuse factor (i.e. K), the safety factor (i.e. Q) and the working voltage deviation value (i.e. Vmax) of the Zener diode is calculated to obtain the power of the Zener diode, so as to determine the type of Zener diode to be selected according to the power of the required Zener diode. Among them, the fuse parameters include the rated voltage, the rated current, the fuse resistance and other parameters, and the specific selection of the fuse parameters for calculating the power of the Zener diode can be selected or set according to actual needs (i.e. the corresponding type of fuse can be selected according to actual needs), which is not limited here.

[0052] The power (i.e., P) of the voltage regulator diode is calculated as follows:

[0053] P=(K*fuse parameter*V MAX )*Q.

[0054] In addition, an embodiment of the utility model further provides an electrical device, wherein the electrical device includes any one of the intrinsically safe power supply protection circuits in the above embodiments.

[0055] It can be understood that the electrical equipment in this embodiment corresponds to the intrinsically safe power supply protection circuit in the above embodiment, and any optional items in the above embodiment can be applied to this embodiment, so they will not be described in detail here.

[0056] Optionally, the electrical equipment can be a mining intrinsically safe switching device (such as a mining switch) or a power supply device for other scenarios or an electrical device such as a switch device. The electrical equipment includes an intrinsically safe power protection circuit, and then the above-mentioned overload protection module 300 can block the connection between the power conversion module 200 and the subsequent voltage stabilization module 400 when the above-mentioned intrinsically safe power protection circuit is in an overcurrent state, thereby achieving the purpose of efficiently controlling the on and off of the power circuit, and the voltage stabilization diode is turned on by the subsequent voltage stabilization module 400 when the circuit is in an overvoltage state, thereby ensuring that the subsequent circuit can not be damaged by the overvoltage or overcurrent of the previous circuit.

[0057] In general technology, a thyristor and a voltage regulator are combined to form a post-stage circuit, which results in the need to occupy a larger PCB board space. For devices with limited PCB board space, extra time is required for design, and the cost of thyristors is relatively high. However, the embodiment of the present application forms a post-stage circuit by combining a fuse and a voltage regulator diode, which can reduce the space occupied by the PCB board and improve the compatibility and flexibility of the PCB board design. The cost of the fuse is relatively low, which saves costs to a great extent, thereby achieving effective power supply protection at a relatively low cost.

[0058] In this embodiment, when the circuit is in an overcurrent condition, the overload protection module 300 blocks the connection between the power conversion module 200 and the subsequent voltage stabilizing module 400 to implement overcurrent protection for the circuit, and when the circuit is in an overvoltage condition, the subsequent voltage stabilizing module 400 triggers the voltage stabilizing diode to conduct, thereby directing the excess voltage to the ground, implementing overvoltage protection for the circuit, thereby preventing the subsequent circuit and external electrical equipment from being damaged by overvoltage or overcurrent; and in this embodiment, the subsequent circuit is formed by combining a fuse and a voltage stabilizing diode, which greatly reduces the space occupied by the PCB board, improves the compatibility and flexibility of the PCB board design, and the cost of the fuse is relatively low, which saves costs to a certain extent.

[0059] It should be noted that the connection described in the above embodiments can be a direct electrical connection or an indirect electrical connection. A direct electrical connection means that two devices are directly connected, and an indirect electrical connection means that other devices such as capacitors and resistors are also connected between the connected A and B.

[0060] The above description is only a specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application.

Claims

1. An intrinsically safe power supply protection circuit, characterized in that: include: A front-stage current blocking module, wherein a first end of the front-stage current blocking module is used to connect to a power source; A power conversion module, a first end of the power conversion module is connected to a second end of the front-stage current blocking module; An overload protection module, wherein a first end of the overload protection module is connected to a second end of the power conversion module; A post-stage voltage stabilizing module, wherein a first end of the post-stage voltage stabilizing module is connected to a second end of the overload protection module; and a second end of the post-stage voltage stabilizing module is used to connect to a voltage output end; Wherein, the overload protection module is used to block the connection between the power conversion module and the subsequent voltage stabilization module when the intrinsically safe power protection circuit is in an overvoltage or overcurrent state.

2. The intrinsically safe power supply protection circuit according to claim 1, characterized in that: The overload protection module is a fuse group; the fuse group includes at least one fuse, and the conductive parts at both ends of each fuse are correspondingly connected to the power conversion module and the post-stage voltage stabilization module; The fuse group is used to fuse when the current value output by the power conversion module is greater than a preset current threshold, so as to disconnect the power conversion module from the subsequent voltage stabilization module.

3. The intrinsically safe power supply protection circuit according to claim 2, characterized in that: Each of the fuses is arranged in the main body of the fuse holder, and conductive parts are respectively arranged at both ends of the fuse holder, and the conductive parts are respectively connected to the input and output terminals of the power conversion module and the post-stage voltage stabilization module; The fuse holder comprises conductive abutting portions respectively arranged at two ends of each of the fuses, and each of the conductive abutting portions is electrically connected to a corresponding fuse and abuts against the conductive portion.

4. The intrinsically safe power supply protection circuit according to claim 3, characterized in that: The conductive abutting portions are arranged on the lower surface of the main body, and each of the conductive abutting portions is connected to a conductive portion of a corresponding fuse.

5. The intrinsically safe power supply protection circuit according to any one of claims 1 to 4, characterized in that: The front-stage current blocking module includes a first diode to an Nth diode connected in series in the same polarity direction, the anode of the first diode is used to access the power supply, and the cathode of the Nth diode is connected to the power conversion module; N≥1.

6. The intrinsically safe power protection circuit according to any one of claims 1 to 4, characterized in that: The post-stage voltage stabilization module includes a plurality of voltage stabilization diodes connected in parallel; wherein one end of each of the voltage stabilization diodes is respectively connected to the second end of the overload protection module, and the other end of each of the voltage stabilization diodes is grounded.

7. The intrinsically safe power supply protection circuit according to any one of claims 1 to 4, characterized in that: The power conversion module is a DC-DC conversion module; the DC input end of the DC-DC conversion module is connected to the front-stage current blocking module, and the DC output end of the DC-DC conversion module is connected to the back-stage voltage stabilization module, which is used to convert the DC input voltage from the power supply received by the front-stage current blocking module into a DC output voltage, wherein the voltage value of the DC output voltage is less than the voltage value of the DC input voltage.

8. The intrinsically safe power supply protection circuit according to any one of claims 1 to 4, characterized in that: The power conversion module includes a power conversion chip and its peripheral circuits.

9. An electrical device, characterized in that: It comprises the intrinsically safe power supply protection circuit as claimed in any one of claims 1 to 8.

10. The electrical device according to claim 9, characterized in that The electrical equipment is an intrinsically safe switching equipment for mining.

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