High-power explosion-proof power supply switching device

Abstract

The present invention provides a high-power explosion-proof power supply switching device, belonging to the technical field of power supplies. A group of switches and Schottky diodes are respectively arranged on the power supply paths of the PT-side AC input power supply and the explosion-proof power supply, and according to the voltages of the PT-side AC input power supply and the explosion-proof power supply, the control module and the driving module are used to automatically control the switching of the above power supply paths to ensure uninterrupted power supply to the load. At the same time, through the combined use of the switches and Schottky diodes, on the one hand, the power of the explosion-proof power supply switching device is increased, so that each explosion-proof power supply in the substation chamber only needs to be equipped with one switching device product, reducing the cost and control complexity; on the other hand, the risk of switching failure caused by adhesion in the prior art when using relays is avoided, ensuring the power supply safety of the load.

Description

Technical Field

[0001] The present invention belongs to the technical field of power supplies, and particularly relates to a high-power explosion-proof power supply switching device. Background Art

[0002] With the improvement of the mining degree of mineral resources in China, the requirements for work safety have also increased accordingly, and the market scale of mine explosion-proof power supplies has been continuously expanding. However, for the extended product of explosion-proof power supplies - high-power explosion-proof power supply switching devices, there are very few similar products on the market currently. The basic control idea for the switching of explosion-proof power supplies is as follows: when the external flameproof battery power supply device needs to be shut down for maintenance, through the automatic conversion of a relay, the 100V AC power supply provided by the voltage transformer inside the flameproof high-voltage switch cabinet can be used as a temporary power supply to supply power to the load; when the maintenance of the flameproof battery power supply device is completed, the flameproof battery power supply device is restored to supply power to the load.

[0003] However, the above switching control scheme has the following several drawbacks: First, the power of the high-power explosion-proof power supply switching device is small, and users need to equip multiple products for simultaneous use; Second, the long-term live use of the relay in the high-power explosion-proof power supply switching device has a risk of adhesion failure, resulting in product failure; Third, the switching time of the relay is relatively long, which may lead to the risk of power failure at the load end. How to improve the safe and reliable power supply to the load is an important problem that needs to be solved currently. Summary of the Invention

[0004] The purpose of the present invention is to provide a high-power explosion-proof power supply switching device, in which a set of switches and Schottky diodes are respectively arranged on the power supply paths of the AC input power supply on the PT side and the explosion-proof power supply, and according to the voltages of the AC input power supply on the PT side and the explosion-proof power supply, the automatic switching control of the above power supply paths is carried out by using a control module and a drive module to ensure the uninterrupted power supply to the load. At the same time, through the combined use of the switches and Schottky diodes, on the one hand, the power of the explosion-proof power supply switching device is increased, so that each explosion-proof power supply in the substation chamber only needs to be equipped with one switching device product, reducing the cost and control complexity; on the other hand, the risk of switching failure caused by adhesion in the prior art when using a relay is avoided, ensuring the power supply safety of the load.

[0005] To achieve the above object, the present invention adopts the following technical solution: A high-power explosion-proof power supply switching device, comprising a PT-side AC input power supply, a first fuse, a first switch, a voltage regulating and rectifying module, a first diode, an AC indicator light, an explosion-proof power supply, a DC indicator light, a second switch, a second diode, a second fuse, and a load. Among them, the PT-side AC input power supply, the first fuse, the first switch, the voltage regulating and rectifying module, and the first diode are connected in series in sequence. The explosion-proof power supply, the second switch, and the second diode are connected in series in sequence. The first diode and the second diode are simultaneously connected to the input end of the second fuse. The output end of the second fuse is connected to the load. The AC indicator light is connected between the voltage regulating and rectifying module and the first diode. The DC indicator light is connected between the explosion-proof power supply and the second switch. The high-power explosion-proof power supply switching device further comprises a control module and a drive module. Two input ends of the control module are respectively connected to the PT-side AC input power supply and the explosion-proof power supply. The output end of the control module is connected to the input end of the drive module. The output end of the drive module is respectively connected to the first switch and the second switch.

[0006] Further, the drive module is used to control the complementary conduction of the first switch and the second switch.

[0007] Further, the first diode and the second diode are Schottky diodes.

[0008] Further, the control module includes a resistor R1, a resistor R2, a resistor R3, a resistor R4, a resistor R5, a resistor R6, a resistor R7, a capacitor C1, a capacitor C2, a diode D1, a diode D2, a light-emitting diode element OPD1, a light-receiving element OPK1, a switching transistor T1, a switching transistor T2, a switching transistor T3, a switch K1, a comparator COM1, an inverter INV, and a rectifying and voltage-regulating unit R / A. One end of the resistor R1 is connected to the explosion-proof power supply, and the other end is grounded through the resistor R2. The common point of the resistors R1 and R2 is connected to one end of the capacitor C1 and the control terminal of the switching transistor T1. The other end of the capacitor C1 and the other end of the switching transistor T1 are grounded. The anode of the light-emitting diode element OPD1 is connected to VDD, and the cathode is connected to one end of the switching transistor T1. VCC is connected to one end of the resistor R3, and the other end of the resistor R3 is connected to one end of the light-receiving element OPK1. The control terminal of the light-receiving element OPK1 is optically coupled to the light-emitting diode element OPD1. The other end of the light-receiving element OPK1 is connected to one end of the resistor R4, and the other end of the resistor R4 is grounded. The capacitor C2 is connected in parallel across the two ends of the resistor R4. VCC is also connected to one end of the resistor R6, and the other end of the resistor R6 is connected to one end of the switching transistor T2. The control terminal of the switching transistor T2 is connected to one end of the resistor R4. The other end of the switching transistor T2 is grounded. VCC is also connected to one end of the switching transistor T3. The control terminal of the switching transistor T3 is connected to one end of the switching transistor T2. The other end of the switching transistor T3 is connected to the control terminal of the switching transistor T2 through the resistor R7. The negative input terminal of the comparator COM1 is connected to one end of the switching transistor T2, and the positive input terminal is connected to the reference voltage Vref. One end of the switch K1 is connected to the control terminal of the switching transistor T2, and the other end is grounded. The control terminal of the switch K1 is connected to the other end of the resistor R5, the anode of the diode D1, and the anode of the diode D2. One end of the resistor R5 is connected to VCC. The explosion-proof power supply is connected to the cathode of the diode D1 through the inverter INV. The PT-side AC input power supply is connected to the cathode of the diode D2 through the rectifying and voltage-regulating unit R / A. The output terminal of the comparator COM1 serves as the output terminal of the control module.

[0009] Further, the rectifying and voltage-regulating unit R / A includes a rectifying unit and a step-down circuit. The input terminal of the rectifying unit is connected to the PT-side AC input power supply. The output terminal of the rectifying unit is connected to the input terminal of the step-down circuit. The output terminal of the step-down circuit is connected to the cathode of the diode D2.

[0010] Further, the switching transistors T1 and T2 are NPN-type triodes, and the switching transistor T3 is a PNP-type triode.

[0011] The beneficial technical effects of the present invention compared with the prior art are as follows: By using the cooperation of a switch and a Schottky diode, uninterrupted power supply to the load is ensured, the cost and control complexity are reduced, the risk of switching failure caused by adhesion of the relay in the prior art is avoided, and the power supply safety of the load is guaranteed. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings described below are only exemplary, and for those of ordinary skill in the art, without creative efforts, other implementation drawings can be obtained according to the provided drawings.

[0013] Figure 1 It is the circuit schematic diagram of the high-power explosion-proof power supply switching device of the present invention;

[0014] Figure 2 It is the circuit structure diagram of the control module of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0015] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the 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.

[0016] The following will first explain the concepts involved in this application in conjunction with the drawings. It should be noted here that the following explanations of each concept are only for making the content of this application easier to understand, and do not represent a limitation on the protection scope of this application; at the same time, without conflict, the embodiments and the features in the embodiments of this application can be combined with each other. The following will refer to the drawings and combine the embodiments to detail this application.

[0017] Combined with the specification appendix Figure 1 A high-power explosion-proof power supply switching device disclosed by the present invention includes a PT-side AC input power supply, a first fuse, a first switch, a voltage regulating and rectifying module, a first diode, an AC indicator light, an explosion-proof power supply, a DC indicator light, a second switch, a second diode, a second fuse, and a load.

[0018] The PT-side AC input power supply, the first fuse, the first switch, the voltage regulating and rectifying module, and the first diode are connected in series in sequence. The AC indicator light is connected between the voltage regulating and rectifying module and the first diode, thus forming the PT-side AC input power supply path. The voltage regulating and rectifying module is used to rectify the AC power supply and adjust its voltage amplitude to meet the load requirements. When the PT-side AC input power supply supplies power normally, the AC indicator light is on.

[0019] The explosion-proof power supply, the second switch, and the second diode are connected in series in sequence. The DC indicator light is connected between the explosion-proof power supply and the second switch, thus forming the explosion-proof power supply path. When the explosion-proof power supply supplies power normally, the DC indicator light is on.

[0020] The first diode and the second diode are both connected to the input end of the second fuse at the same time. The output end of the second fuse is connected to the load. The above-mentioned first diode and second diode are both Schottky diodes. By controlling the above-mentioned first switch or second switch and utilizing the one-way conduction characteristic of the diode, the switching of different power supply paths is carried out to ensure the uninterrupted power supply of the load. The setting of the fuse plays an overcurrent protection role for the circuit.

[0021] The high-power explosion-proof power supply switching device further includes a control module and a drive module. The two input ends of the control module are respectively connected to the PT-side AC input power supply and the explosion-proof power supply. The output end of the control module is connected to the input end of the drive module. The output end of the drive module is respectively connected to the first switch and the second switch. The control module generates an indication signal according to the voltages of the PT-side AC input power supply and the explosion-proof power supply. The drive module controls the first switch and the second switch to conduct complementarily according to this indication signal, that is, when the first switch conducts, the second switch is controlled to disconnect, and when the first switch disconnects, the second switch is controlled to conduct.

[0022] It should be noted that different types of switches can be selected as the first switch and the second switch. For example, the first switch selects an NMOS transistor and the second switch selects a PMOS transistor, or the second switch selects an NMOS transistor and the first switch selects a PMOS transistor, and the same drive signal is applied to the first switch and the second switch to achieve the complementary conduction of the first switch and the second switch; the same type of switches can also be selected as the first switch and the second switch. For example, both the first switch and the second switch are NMOS transistors or both the first switch and the second switch are PMOS transistors, and two inverted drive signals are applied to the first switch and the second switch to achieve the complementary conduction of the first switch and the second switch; a single-pole double-throw switch can also be selected to achieve the complementary conduction of the above-mentioned first switch and the second switch; other interlock circuits can also be used to achieve the complementary conduction of the above-mentioned first switch and the second switch.

[0023] Combined with the specification appendix Figure 2, the control module of the present invention includes resistor R1, resistor R2, resistor R3, resistor R4, resistor R5, resistor R6, resistor R7, capacitor C1, capacitor C2, diode D1, diode D2, light-emitting diode element OPD1, light-receiving element OPK1, switching transistor T1, switching transistor T2, switching transistor T3, switch K1, comparator COM1, inverter INV and rectification and voltage regulation unit R / A. One end of resistor R1 is connected to the explosion-proof power supply, and the other end is grounded through resistor R2. The common point of resistors R1 and R2 is connected to one end of capacitor C1 and the control end of switching transistor T1. The other end of capacitor C1 and the other end of switching transistor T1 are grounded. The anode of light-emitting diode element OPD1 is connected to VDD, and the cathode is connected to one end of switching transistor T1. VCC is connected to one end of resistor R3, and the other end of resistor R3 is connected to one end of light-receiving element OPK1. The control end of light-receiving element OPK1 is optically coupled to light-emitting diode element OPD1. The other end of light-receiving element OPK1 is connected to one end of resistor R4, and the other end of resistor R4 is grounded. Capacitor C2 is connected in parallel across both ends of resistor R4. VCC is also connected to one end of resistor R6, and the other end of resistor R6 is connected to one end of switching transistor T2. The control end of switching transistor T2 is connected to one end of resistor R4, and the other end of switching transistor T2 is grounded. VCC is also connected to one end of switching transistor T3. The control end of switching transistor T3 is connected to one end of switching transistor T2, and the other end of switching transistor T3 is connected to the control end of switching transistor T2 through resistor R7. The negative input terminal of comparator COM1 is connected to one end of switching transistor T2, and the positive input terminal is connected to reference voltage Vref. One end of switch K1 is connected to the control end of switching transistor T2, and the other end of switch K1 is grounded. The control end of switch K1 is connected to the other end of resistor R5, the anode of diode D1, and the anode of diode D2. One end of resistor R5 is connected to VCC. The explosion-proof power supply is connected to the cathode of diode D1 through inverter INV. The PT-side AC input power supply is connected to the cathode of diode D2 through rectification and voltage regulation unit R / A. The output terminal of comparator COM1 serves as the output terminal of the control module.

[0024] The rectification and voltage regulation unit R / A includes a rectification unit and a buck circuit. The input terminal of the rectification unit is connected to the PT-side AC input power supply. The output terminal of the rectification unit is connected to the input terminal of the buck circuit. The output terminal of the buck circuit is connected to the cathode of diode D2.

[0025] The switching transistors T1 and T2 are NPN-type triodes, and the switching transistor T3 is a PNP-type triode. The rectification unit preferably adopts a full-bridge controlled rectification circuit, and the buck circuit preferably adopts a BUCK circuit. The comparator COM1 can also be replaced by an operational amplifier. The light-emitting diode element OPD1 and the light-receiving element OPK1 can also be replaced by an integrated optocoupler module or an optocoupler chip.

[0026] The following combines the description Figure 1 and the Figure 2 Briefly introduce the working principle of the present invention: When the explosion-proof power supply is powered on, the voltage of the explosion-proof power supply drives the switch tube T1 to conduct through the voltage-dividing resistors R1 and R2 at point A, the light-emitting diode element OPD1 conducts, and its light path drives the light-receiving element OPK1 to conduct, thereby controlling the switch tube T2 to conduct. The control end of the switch tube T3 is pulled low, causing the switch tube T3 to also be in a conducting state, thus forming a bias current path for VCC, the switch tube T3, and the resistor R7, enabling the switch tube T2 to maintain a conducting state. The negative input of the comparator COM1 is pulled low, and the comparator COM1 outputs a high level as an indication signal and inputs it to the drive module. The drive module controls the second switch to conduct and the first switch to disconnect, and supplies power to the load by using the explosion-proof power supply through the second switch, the second diode, and the second fuse. The high level of the explosion-proof power supply voltage at point A is converted to a low level through the inverter INV, thereby clamping the control end voltage of the switch K1 at about 0.7V, making it unable to conduct.

[0027] When the explosion-proof power supply is powered off, the control end voltage of the switch K1 is released from the 0.7V clamp (since the high-power explosion-proof power supply switching device of the present invention is applied to the underground coal mine substation chamber, which belongs to the first-class load, so it is almost impossible for the PT-side AC input power supply and the explosion-proof power supply to be powered off simultaneously). K1 conducts, causing the switch tube T2 to disconnect. The negative input of the comparator COM1 is pulled high, and the comparator COM1 outputs a low level as an indication signal and inputs it to the drive module. The drive module controls the first switch to conduct and the second switch to disconnect, and supplies power to the load by using the PT-side AC input power supply through the first fuse, the first switch, the voltage regulation and rectification module, the first diode, and the second fuse.

[0028] The above-described embodiments and / or implementation manners are only used to illustrate the preferred embodiments and / or implementation manners for implementing the technology of the present invention, and do not impose any formal restrictions on the implementation manners of the technology of the present invention. Any person skilled in the art, without departing from the scope of the technical means disclosed in the content of the present invention, may make some changes or modifications to other equivalent embodiments, but should still be regarded as the same technology or embodiment as the present invention in essence.

[0029] In this text, specific examples are used to elaborate on the principles and implementation manners of the present application. The description of the above embodiments is only used to help understand the method and its core idea of the present application. The above is only the preferred implementation manner of the present application. It should be noted that due to the limited nature of literal expression and objectively infinite specific structures, for those of ordinary skill in the art, without departing from the principles of the present application, several improvements, refinements or changes can be made, or the above technical features can be combined in an appropriate manner; these improvements, refinements, changes or combinations, or directly applying the inventive concept and technical solution to other occasions without improvement, shall all be regarded as the protection scope of the present application.

Claims

1. A high-power explosion-proof power switching device, comprising an AC input power supply on the PT side, a first fuse, a first switch, a voltage regulating and rectifying module, a first diode, an AC indicator light, an explosion-proof power supply, a DC indicator light, a second switch, a second diode, a second fuse, and a load, wherein the AC input power supply on the PT side, the first fuse, the first switch, the voltage regulating and rectifying module and the first diode are sequentially connected in series, the explosion-proof power supply, the second switch, and the second diode are sequentially connected in series, the first diode and the second diode are simultaneously connected to the input end of the second fuse, the output end of the second fuse is connected to the load, the AC indicator light is connected between the voltage regulating and rectifying module and the first diode, and the DC indicator light is connected between the explosion-proof power supply and the second switch, characterized in that: The high-power explosion-proof power switching device also includes a control module and a drive module, wherein two input ends of the control module are respectively connected to the PT-side AC input power supply and the explosion-proof power supply, the output end of the control module is connected to the input end of the drive module, and the output end of the drive module is respectively connected to the first switch and the second switch; The control module includes a resistor R1, a resistor R2, a resistor R3, a resistor R4, a resistor R5, a resistor R6, a resistor R7, a capacitor C1, a capacitor C2, a diode D1, a diode D2, a light-emitting diode element OPD1, a light-receiving element OPK1, a switch tube T1, a switch tube T2, a switch tube T3, a switch K1, a comparator COM1, an inverter INV and a rectifier and voltage regulating unit R / A, one end of the resistor R1 is connected to an explosion-proof power supply, and the other end is grounded through the resistor R2, a common point of the resistors R1 and R2 is connected to one end of the capacitor C1 and the control end of the switch tube T1, the other end of the capacitor C1 and the other end of the switch tube T1 are grounded, the anode of the light-emitting diode element OPD1 is connected to VDD, and the cathode is connected to one end of the switch tube T1; VCC is connected to one end of the resistor R3, the other end of the resistor R3 is connected to one end of the light receiving element OPK1, the control end of the light receiving element OPK1 is optically coupled with the light emitting diode element OPD1, the other end of the light receiving element OPK1 is connected to one end of the resistor R4, the other end of the resistor R4 is grounded, and the capacitor C2 is connected in parallel to both ends of the resistor R4; VCC is also connected to one end of the resistor R6, the other end of the resistor R6 is connected to one end of the switch tube T2, the control end of the switch tube T2 is connected to one end of the resistor R4, and the other end of the switch tube T2 is grounded; VCC is also connected to one end of the switch tube T3, the control end of the switch tube T3 is connected to one end of the switch tube T2, and the other end of the switch tube T3 is connected to the control end of the switch tube T2 through the resistor R7; the negative input end of the comparator COM1 is connected to one end of the switch tube T2, and the positive input end is connected to the reference voltage Vref; one end of the switch tube T2 is the collector of the switch tube T2, and the other end of the switch tube T2 is the emitter of the switch tube T2; One end of the switch K1 is connected to the control end of the switch tube T2, and the other end of the switch K1 is grounded. The control end of the switch K1 is connected to the other end of the resistor R5, the anode of the diode D1 and the anode of the diode D2. One end of the resistor R5 is connected to VCC. The explosion-proof power supply is connected to the cathode of the diode D1 through the inverter INV. The AC input power supply on the PT side is connected to the cathode of the diode D2 through the rectifier and voltage regulator unit R / A. The output end of the comparator COM1 serves as the output end of the control module.

2. The high-power explosion-proof power switching device according to claim 1, characterized in that: The driving module is used to control the first switch and the second switch to be complementary turned on.

3. The high-power explosion-proof power switching device according to claim 1, characterized in that: The first diode and the second diode are Schottky diodes.

4. The high-power explosion-proof power switching device according to claim 1, characterized in that: The rectifier and voltage regulator unit R / A includes a rectifier unit and a step-down circuit, wherein the input end of the rectifier unit is connected to the PT side AC input power supply, the output end of the rectifier unit is connected to the input end of the step-down circuit, and the output end of the step-down circuit is connected to the cathode of the diode D2.

5. The high-power explosion-proof power switching device according to claim 1, characterized in that: The switch tube T1 and the switch tube T2 are NPN type transistors, and the switch tube T3 is a PNP type transistor.

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