Mining flame-proof and intrinsic safety type direct-current stabilized power supply circuit

Abstract

The utility model belongs to the technical field of mining power supplies, and particularly relates to a mining flame-proof and intrinsic safety type direct-current stabilized power supply circuit, which comprises an input circuit, a charging circuit and an intrinsic safety output circuit, and is characterized in that the input circuit is used for supplying power to the whole direct-current stabilized power supply circuit; the charging circuit charges the backup battery pack when the power supply circuit normally supplies power; after the intrinsic safety output circuit receives and reduces the direct current voltage output by the input circuit or the direct current voltage output by the backup battery pack, the intrinsic safety output circuit outputs working voltage under the limitation of the protection circuit; the charging circuit is added in the power supply circuit, and the backup battery pack is charged when an external power supply normally supplies power; when an external power supply is suddenly powered off, the backup battery pack begins to discharge and normally outputs working voltage for the power supply circuit, so that normal working of load equipment is ensured, and production safety and high efficiency are provided; according to the utility model, the protection circuit is arranged to control the on-off of the power supply circuit, so that the circuit is prevented from being burnt out by current surge.

Description

Technical Field

[0001] The utility model belongs to the technical field of mine power supplies, and particularly relates to a mine flameproof and intrinsically safe DC regulated power supply circuit. Background Art

[0002] Existing mine flameproof and intrinsically safe DC regulated power supplies are not equipped with backup batteries. During the use of mine DC regulated power supplies, if a sudden power outage occurs in a coal mine, all the load devices connected to the power supply will stop working. For some key control devices, communication devices, lighting devices, and ventilation safety guarantee devices, once the power is cut off, the coal mine will face production guarantee problems and the life safety problems of the staff, and the responsibility is significant.

[0003] If the DC regulated power supply has its own backup power supply, when a sudden power outage occurs in the coal mine, the backup power supply can also enable the load devices to continue working for several hours, providing time for the safe evacuation of coal mine workers or equipment maintenance, and ensuring the normal operation and safe production of underground equipment. Therefore, how to design a power supply that can still supply power to some key control devices, communication devices, lighting devices, and ventilation safety guarantee devices in the event of a sudden power outage in a coal mine is an urgent problem to be solved in the modern mine safety device technology. Summary of the Utility Model

[0004] In view of this, the utility model provides a mine flameproof and intrinsically safe DC regulated power supply circuit, aiming to provide a DC regulated power supply circuit with a backup battery, and solve the problem that when the equipment suddenly loses power, some key control devices, communication devices, lighting devices, and ventilation safety guarantee devices cannot continue to work, which is likely to lead to abnormal operation and potential safety hazards.

[0005] In order to achieve the above purpose, the technical solution adopted by the utility model is as follows:

[0006] The mine flameproof and intrinsically safe DC regulated power supply circuit includes: an input circuit, a charging circuit, and an intrinsically safe output circuit, where:

[0007] The input circuit is used to supply power to the entire DC regulated power supply circuit. The input circuit includes a power input module, which steps down the 660V AC input voltage using the power input module and outputs two 24V DC voltages. One 24V DC voltage is directly adjusted by the intrinsically safe output circuit and used as the working voltage for voltage output; the other 24V DC voltage is fed into the intrinsically safe output circuit after passing through the charging circuit.

[0008] The charging circuit includes a CN3765 charging chip and a backup battery pack. The CN3765 charging chip is used to convert the 24V DC voltage output by the input circuit into a DC21.9V voltage to charge the backup battery pack. On this basis, when the backup battery pack discharges, it outputs a 19.2V DC voltage;

[0009] The intrinsically safe output circuit includes several DC-DC isolation modules and several protection circuits. After each DC-DC isolation module receives the 24V DC voltage output from the input circuit or the 19.2V DC voltage output from the backup battery pack, it steps down to DC12V and outputs the working voltage under the limitation of the protection circuit;

[0010] The protection circuit includes two identical and series-connected overvoltage and overcurrent protection circuits. Each overvoltage and overcurrent protection circuit includes:

[0011] The current sampling module includes a sampling resistor R1 connected in series in the main circuit of the overvoltage and overcurrent protection circuit, which is used to collect the magnitude of the current flowing through the main circuit and generate a current signal;

[0012] The voltage sampling module includes sampling resistors R2 and R3 connected in parallel in the main circuit of the overvoltage and overcurrent protection circuit, which are used to collect the magnitude of the voltage in the main circuit and generate a voltage signal;

[0013] The control module includes a transient suppression chip U2 connected in parallel in the main circuit of the overvoltage and overcurrent protection circuit. The transient suppression chip U2 receives the current signal and the voltage signal, compares them with the internally preset current threshold and voltage threshold respectively, and outputs a control signal for controlling whether the switch module works or not;

[0014] The switch module includes a field effect transistor U1 and an internal drive circuit connected in series in the main circuit of the overvoltage and overcurrent protection circuit. The switch module receives the control signal, controls the internal drive circuit to drive the on and off of the field effect transistor U1, and thus controls the on and off of the entire power supply circuit.

[0015] Preferably, in the input circuit, the input voltage level range of the power input module is AC95V - 726V.

[0016] Further, the input end of the charging circuit is connected to the output end of the input circuit, and two first diodes are also connected in series at the input end of the charging circuit, which are used to prevent the current from flowing back through the CN3765 charging chip into the power input module when the backup battery pack discharges;

[0017] The charging circuit further includes an intermediate circuit, which is arranged between the CN3765 charging chip and the backup battery pack. On the one hand, it is used to charge the backup battery pack by using the CN3765 charging chip. On the other hand, when the backup battery pack discharges, the circuit is connected to the DC-DC isolation module to supply power to the protection circuit. On this basis, the intermediate circuit also connects an output terminal to between the output terminal of the input circuit and the input terminal of the intrinsically safe output circuit through a second diode, and a third diode is arranged between the output terminal of the input circuit and the output terminal of the intermediate circuit to prevent the current from flowing reversely into the input circuit between the input circuit and the intrinsically safe output circuit when the backup battery pack discharges. In addition, a rotary switch is also connected in series on the intermediate circuit.

[0018] Preferably, in the intrinsically safe output circuit, a plurality of DC-DC isolation modules are arranged in parallel, and each DC-DC isolation module is equipped with a protection circuit.

[0019] The beneficial effects of the present invention are as follows:

[0020] Generally speaking, the present invention adds a charging circuit between the input circuit and the intrinsically safe output circuit in the power supply circuit. When the external power supply is normally powered, on the basis of the power supply circuit normally outputting the working voltage, the CN3765 charging chip is used to charge the backup battery pack at the same time. When the external power supply suddenly cuts off, the backup battery pack starts to discharge, and the power supply circuit still normally outputs the working voltage, ensuring the normal operation of some key load devices such as subsequent control devices, communication devices, lighting devices, and ventilation safety guarantee devices, and providing the safety and efficiency of production.

[0021] Specifically, the present invention sets a protection circuit in the intrinsically safe output circuit, uses the current sampling module and voltage sampling module in the protection circuit to collect the current and voltage flowing through the overvoltage and overcurrent protection circuit. After inputting the collected data into the control module, the transient suppression chip U2 in the control module outputs the control of the switch module according to the obtained data, thereby controlling the on and off of the entire power supply circuit to prevent the occurrence of current surges from burning out the circuit. In addition, the present invention also has an intermediate circuit in the charging circuit, which on the one hand provides a bridge for the charging process and discharging process of the charging circuit; on the other hand, through the arrangement of a plurality of diodes on the intermediate circuit, it prevents the occurrence of reverse current during the charging process and discharging process, resulting in danger. Description of the Drawings

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0023] Figure 1 It is a schematic diagram of the overall framework of the DC regulated power supply circuit in the present invention;

[0024] Figure 2 It is a schematic diagram of the framework of the charging circuit in the present invention;

[0025] Figure 3 It is a schematic diagram of the framework of the protection circuit in the present invention;

[0026] Figure 4 It is a schematic diagram of the principle of the overvoltage and overcurrent protection circuit in the present invention. Detailed implementation manners

[0027] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0028] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, so it cannot be understood as a limitation of the present invention; the terms "first", "second", "third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In addition, unless otherwise clearly defined and limited, the terms "installation", "connection", "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the internal communication of two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0029] The following will detail the technical solutions of the present invention with reference to the drawings.

[0030] In this technical solution, as Figure 1 shown, the mine flameproof and intrinsically safe DC regulated power supply circuit includes: an input circuit 1, a charging circuit 2, and an intrinsically safe output circuit 3, where:

[0031] The input circuit 1 is used to supply power to the entire DC regulated power supply circuit. The input circuit 1 includes a power input module. The 660V AC input voltage is stepped down by the power input module and then two 24V DC voltages are output. One 24V DC voltage is directly adjusted by the intrinsically safe output circuit 3 and then output as the working voltage; the other 24V DC voltage is fed into the intrinsically safe output circuit 3 after passing through the charging circuit 2. Among them, the input voltage level range of the power input module is AC95V - 726V.

[0032] As Figure 1-2 shown, the charging circuit 2 includes a CN3765 charging chip 202 and a backup battery pack 203. The CN3765 charging chip 202 is used to convert the 24V DC voltage output by the input circuit 1 into a DC21.9V voltage to charge the backup battery pack 203. On this basis, when the backup battery pack 203 discharges, it outputs a 19.2V DC voltage.

[0033] Among them, the input end of the charging circuit 2 is connected to the output end of the input circuit 1, and a first diode 204 is also connected in series at the input end of the charging circuit 2, which is used to prevent the current from flowing back through the CN3765 charging chip 202 into the power input module when the backup battery pack 203 discharges; in addition, the charging circuit 2 also includes an intermediate circuit 201. The intermediate circuit 201 is arranged between the CN3765 charging chip 202 and the backup battery pack 203. On the one hand, it is used to charge the backup battery pack 203 by the CN3765 charging chip 202, and on the other hand, it is used to connect the circuit to the input end of the intrinsically safe output circuit 3 when the backup battery pack 203 discharges.

[0034] On this basis, the intermediate circuit 201 also connects an output end to between the output end of the input circuit 1 and the input end of the intrinsically safe output circuit 3 through a second diode 205, and a third diode 101 is arranged between the output end of the input circuit 1 and the output end of the intermediate circuit 201 to prevent the current from flowing reversely into the input circuit 1 between the input circuit 1 and the intrinsically safe output circuit 3 when the backup battery pack 203 discharges.

[0035] In addition, a rotary switch is also connected in series on the intermediate circuit 201, which is closed before the DC regulated power supply circuit is specifically installed in the coal mine to prevent the backup battery pack 203 from consuming power during transportation.

[0036] Based on the above embodiments, the design of the intermediate circuit 201 provides a bridge for the charging process and the discharging process of the charging circuit 2. By utilizing the unidirectionality of the diode, the current flow direction during the charging process and the discharging process is limited, preventing the reverse flow of current and avoiding potential hazards.

[0037] In this technical solution, as Figure 1-3 shown, the intrinsically safe output circuit 3 includes a plurality of DC-DC isolation modules 301 and a plurality of protection circuits 302. After each DC-DC isolation module 301 receives the 24V DC voltage output from the input circuit 1 or the 19.2V DC voltage output from the backup battery pack 203, it steps down the voltage to DC12V and outputs the working voltage under the limitation of the protection circuit 302.

[0038] Among them, the protection circuit 302 includes two identical and series-connected overvoltage and overcurrent protection circuits 303. As Figure 4 shown, each overvoltage and overcurrent protection circuit 303 includes:

[0039] A current sampling module, including a sampling resistor R1 connected in series in the main circuit of the overvoltage and overcurrent protection circuit 303, which is used to collect the magnitude of the current flowing through the main circuit and generate a current signal.

[0040] A voltage sampling module, including sampling resistors R2 and R3 connected in parallel in the main circuit 303 of the overvoltage and overcurrent protection circuit, which is used to collect the magnitude of the voltage in the main circuit and generate a voltage signal.

[0041] A control module, including a transient suppression chip U2 connected in parallel in the main circuit of the overvoltage and overcurrent protection circuit 303. The transient suppression chip U2 receives the current signal and the voltage signal, compares them with the internally preset current threshold and voltage threshold respectively, and outputs a control signal for controlling whether the switch module works or not. When the current signal and / or the voltage signal is greater than the current threshold and / or the voltage threshold, the control module outputs a control signal to turn off the switch module.

[0042] A switch module, including a field effect transistor U1 and an internal drive circuit connected in series in the main circuit of the overvoltage and overcurrent protection circuit 303. The switch module receives the control signal, controls the internal drive circuit to drive the on / off of the field effect transistor U1, and further controls the on / off of the entire power supply circuit to prevent current surges from burning out the circuit.

[0043] In the intrinsically safe output circuit of the present utility model, a plurality of DC-DC isolation modules 301 are arranged in parallel as needed, and each DC-DC isolation module 301 is provided with a protection circuit 302. In addition, the entire DC regulated power supply circuit provided by the present utility model is an intrinsically safe circuit, that is, an intrinsically safe type.

[0044] Specifically, when using the product based on the DC regulated power supply circuit provided by the present utility model to supply power to various equipment in coal mines, the mine explosion-proof and intrinsically safe DC regulated power supply based on the DC regulated power supply circuit provided by the utility model is connected to each load through wires, etc., so as to realize that when a sudden power outage occurs in the coal mine, the power supply can still supply power to each load within a short time, achieving the purpose of safe production and efficient production.

[0045] Finally, it should be noted that the above are only the preferred embodiments of the present utility model and are not used to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, for those skilled in the art, they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. The intrinsically safe and flameproof DC regulated power supply circuit for mine use is characterized in that, Comprising: An input circuit, a charging circuit, and an intrinsically safe output circuit, where: The input circuit is used to supply power to the entire DC regulated power supply circuit. The input circuit includes a power input module that steps down the 660V AC input voltage and outputs two 24V DC voltages. One 24V DC voltage is directly adjusted by the intrinsically safe output circuit and used as the working voltage for voltage output; the other 24V DC voltage is fed into the intrinsically safe output circuit after passing through the charging circuit. The charging circuit includes a CN3765 charging chip and a backup battery pack. The CN3765 charging chip is used to convert the 24V DC voltage output by the input circuit into a DC21.9V voltage to charge the backup battery pack. On this basis, when the backup battery pack discharges, it outputs a 19.2V DC voltage. The intrinsically safe output circuit includes a number of DC-DC isolation modules and a number of protection circuits. After each DC-DC isolation module receives the 24V DC voltage output from the input circuit or the 19.2V DC voltage output from the backup battery pack, it steps down to DC12V and outputs the working voltage under the limitation of the protection circuit. The protection circuit includes two identical and series-connected overvoltage and overcurrent protection circuits. Each overvoltage and overcurrent protection circuit includes: A current sampling module, including a sampling resistor R1 connected in series in the main circuit of the overvoltage and overcurrent protection circuit, which is used to collect the magnitude of the current flowing through the main circuit and generate a current signal. A voltage sampling module, including sampling resistors R2 and R3 connected in parallel in the main circuit of the overvoltage and overcurrent protection circuit, which is used to collect the magnitude of the voltage in the main circuit and generate a voltage signal. A control module, including a transient suppression chip U2 connected in parallel in the main circuit of the overvoltage and overcurrent protection circuit. The transient suppression chip U2 receives the current signal and the voltage signal, compares them with the internally preset current threshold and voltage threshold respectively, and outputs a control signal for controlling whether the switch module works or not. A switch module, including a field effect transistor U1 and an internal drive circuit connected in series in the main circuit of the overvoltage and overcurrent protection circuit. The switch module receives the control signal, controls the internal drive circuit to drive the on / off of the field effect transistor U1, and thus controls the on / off of the entire power supply circuit.

2. The intrinsically safe and flameproof DC regulated power supply circuit for mine use according to claim 1, characterized in that: In the input circuit, the input voltage level range of the power input module is AC95V - 726V.

3. The intrinsically safe and flameproof DC regulated power supply circuit for mine use according to claim 2, characterized in that: The input end of the charging circuit is connected to the output end of the input circuit, and two first diodes are also connected in series at the input end of the charging circuit, which are used to prevent the current from flowing back through the CN3765 charging chip into the power input module when the backup battery pack discharges. The charging circuit further includes an intermediate circuit, which is disposed between the CN3765 charging chip and the backup battery pack. On the one hand, it is used to charge the backup battery pack by using the CN3765 charging chip. On the other hand, when the backup battery pack discharges, the circuit is connected to the DC-DC isolation module to supply power to the protection circuit. On this basis, the intermediate circuit also connects an output terminal to between the output terminal of the input circuit and the input terminal of the intrinsically safe output circuit through a second diode, and a third diode is provided between the output terminal of the input circuit and the output terminal of the intermediate circuit to prevent the current from flowing reversely into the input circuit between the input circuit and the intrinsically safe output circuit when the backup battery pack discharges. In addition, a rotary switch is also connected in series on the intermediate circuit.

4. The intrinsically safe type DC regulated power supply circuit for mine flameproof and intrinsically safe applications according to claim 3, characterized in that: In the intrinsically safe output circuit, a plurality of DC-DC isolation modules are arranged in parallel, and each of the DC-DC isolation modules is provided with a corresponding protection circuit.

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