阅读说明：本技术 一种大功率矿用稳压电路 (High-power mining voltage stabilizing circuit ) 是由 张�杰 于 2019-10-29 设计创作，主要内容包括：本发明公开了一种大功率矿用稳压电路,包括稳压单元、触发单元、大功率保护单元,所述稳压单元的输出端与所述触发单元的输入端相连接,所述触发单元的输出端与所述大功率保护单元的输入端相连接,所述稳压单元、所述大功率保护单元分别外接本安电源。本发明的电路设计简单,装置容易,可像稳压二极管一样简单的并联在电源电路中即可,但又具有较大可承受功率容限,在含易燃易爆气体的矿井下,通过与本安型电源的配合使用,即使是遇到高电压或者强电流,也能稳定电源电压,防止器件烧毁产生火花或者表面温度超过安全值,保证井下电子设备正常运行,防止矿井下的安全事故的发生。(The invention discloses a high-power mining voltage stabilizing circuit which comprises a voltage stabilizing unit, a triggering unit and a high-power protection unit, wherein the output end of the voltage stabilizing unit is connected with the input end of the triggering unit, the output end of the triggering unit is connected with the input end of the high-power protection unit, and the voltage stabilizing unit and the high-power protection unit are respectively externally connected with an intrinsic safety power supply. The circuit of the invention has simple design and easy device, can be simply connected in parallel in a power circuit just like a voltage stabilizing diode, but has larger bearable power tolerance, and can stabilize the power voltage even encountering high voltage or strong current by matching with the intrinsic safety type power supply under a mine containing inflammable and explosive gas, thereby preventing the device from burning to generate spark or preventing the surface temperature from exceeding a safety value, ensuring the normal operation of underground electronic equipment and preventing the safety accident under the mine.)

1. The high-power mining voltage stabilizing circuit is characterized by comprising a voltage stabilizing unit, a triggering unit and a high-power protection unit, wherein the output end of the voltage stabilizing unit is connected with the input end of the triggering unit, the output end of the triggering unit is connected with the input end of the high-power protection unit, and the voltage stabilizing unit and the high-power protection unit are respectively externally connected with an intrinsic safety power supply.

2. The high-power mining voltage stabilizing circuit according to claim 1, wherein the voltage stabilizing unit comprises a Zener diode D1, the K pole of the Zener diode D1 is connected with the output positive terminal of the intrinsic safety power supply, and the A pole of the Zener diode D1 is connected with the input end of the trigger unit.

3. The high power mining voltage stabilizing circuit of claim 2, wherein when a reverse voltage between the K pole and the A pole of the Zener diode D1 reaches a certain value, a reverse current flows through the Zener diode D1 and flows through the trigger unit to the DGND terminal.

4. The high-power mining voltage stabilizing circuit according to claim 2, wherein the trigger unit comprises a chip resistor R1 and a chip capacitor C1, one end of the chip resistor R1 connected in parallel with the chip capacitor C1 is connected with the A pole of the Zener diode D1, and the other end of the chip resistor R1 connected in parallel with the chip capacitor C1 is connected with the output negative pole of the intrinsic safety power supply.

5. The high-power mining voltage stabilizing circuit according to claim 4, wherein a current passing through the voltage stabilizing unit passes through the chip resistor R1 and forms a voltage difference across the chip resistor R1, and the voltage difference reaches a trigger threshold of the high-power protection unit and serves as a trigger signal to trigger the high-power protection unit so as to protect a front-end circuit from being damaged by a large current.

6. The high-power mining voltage stabilizing circuit according to claim 5, wherein the high-power protection unit comprises a chip resistor R2 and a silicon controlled rectifier SCR1, one end of the chip resistor R2 is connected with the A pole of the Zener diode D1, the other end of the chip resistor R2 is connected with the G pole of the silicon controlled rectifier SCR1, the A pole of the silicon controlled rectifier SCR1 is connected with the output positive terminal of the intrinsic safety power supply, and the K pole of the silicon controlled rectifier SCR1 is connected with the output negative pole of the intrinsic safety power supply.

7. The high-power mining voltage stabilizing circuit according to claim 6, wherein the voltage difference output by the trigger unit reaches the trigger voltage value of the SCR1, and then the voltage difference triggers the conduction of the two ends of the A pole and the K pole of the SCR1 to form a circuit, so that a power circuit forms a short circuit, and further the intrinsic safety power supply supplied by the front end is triggered to perform short circuit overcurrent protection, and the power supply is cut off in time, and further overvoltage protection is formed.

8. The high-power mining voltage stabilizing circuit of claim 1, wherein the intrinsically safe power supply is a mining intrinsically safe direct current stabilized power supply.

Technical Field

The invention relates to a high-power mining voltage stabilizing circuit, and belongs to the technical field of voltage stabilizing protection of power supply equipment.

Background

With the rapid advance of society, the electric equipment increases day by day, and stable voltage source is essential to the electric equipment, especially to high and new science and technology and accurate equipment that the voltage required is strict. The instability of the power supply voltage can cause the circuit to be incapable of working normally, can cause fatal damage to electronic equipment, can accelerate the aging of the equipment and influence the service life, and leads a user to be confronted with the trouble of maintenance or need to update the equipment in a short period, thereby wasting resources; the underground coal mine environment is special, and inflammable and explosive substances such as gas, dust, carbon monoxide and the like exist, so that power supplies and power conversion circuits of various communication, monitoring, instruments, automation and other system equipment under the mine must meet the explosion-proof requirement, and the intrinsic safety type is the best explosion-proof form. By intrinsically safe circuit is meant a circuit that, under normal operation or a prescribed fault condition, does not ignite a prescribed explosive gas environment with any spark or effect produced. Therefore, for some mining equipment, the requirement on stable voltage is higher, the instability of power supply voltage can cause device damage, sparks are generated or the surface temperature of components exceeds a safety value, and safety accidents can be caused in complex environments such as mines.

In most circuit designs, a simpler voltage stabilizing circuit is formed by only one voltage stabilizing diode, a load is connected with the voltage stabilizing diode in parallel, and the voltage at two ends of the voltage stabilizing diode is stable and unchangeable, so that the load obtains stable direct current voltage. The voltage stabilizing circuit is simple in design and convenient to apply, but if the voltage stabilizing circuit is not noticed in practical use, the over-power over-current damage of a device is easily caused. The power of the voltage stabilizing diode is not very large, the voltage stabilizing diode has limit current and limit power, the voltage stabilizing diode cannot be overrun during design and use, when the current flowing through the voltage stabilizing diode is overloaded, the voltage stabilizing diode is easy to break down, sparks are generated or the surface temperature of the voltage stabilizing diode exceeds a safe value, and the voltage stabilizing diode is not suitable for explosive gas environments and combustible dust environments.

Disclosure of Invention

Drawings

Fig. 1 is a topological diagram of a preferred embodiment of the present invention.

Fig. 2 is a schematic circuit connection diagram of a preferred embodiment of the present invention.

Detailed Description

The invention is further described below with reference to the accompanying drawings. The following examples are only for illustrating the technical solutions of the present invention more clearly, and the protection scope of the present invention is not limited thereby.

In order to prevent the electronic equipment from being abnormal or failing due to voltage fluctuation, a circuit design must include a voltage stabilizing circuit with voltage stabilizing capability, and a zener diode has the characteristic that in a reverse breakdown state, although the current varies in a large range, the voltage across the zener diode is basically unchanged, and is often used to form the simplest voltage stabilizing circuit: the load RL is connected with the voltage-stabilizing tube in parallel.

The voltage stabilizing circuit is simple in design, widely applied to various circuits, but has certain limitation. The power of the voltage stabilizing diode is not very high generally, the power of the common voltage stabilizing diode is 1W, 2W and the like, the power cannot exceed the limit during design and use, when the current flowing through the voltage stabilizing diode exceeds a load or the voltage at two ends of the diode is too high and exceeds the rated power of the voltage stabilizing diode, the diode can be burnt out, sparks are generated or the surface temperature of a device exceeds a safety value, the intrinsic safety performance of mining equipment is further influenced, and the voltage stabilizing diode is not suitable for being used in the underground coal mine and other environments containing explosive gases such as gas.

As shown in fig. 1, the invention provides a voltage stabilizing circuit for a mine, which comprises a voltage stabilizing unit, a triggering unit and a high-power protection unit, wherein an output end of the voltage stabilizing unit is connected with an input end of the triggering unit, an output end of the triggering unit is connected with an input end of the high-power protection unit, and the voltage stabilizing unit and the high-power protection unit are respectively externally connected with an intrinsic safety power supply.

Further, as shown in fig. 2, the voltage stabilizing unit includes a zener diode D1, a K pole of the zener diode D1 is connected to the output positive terminal of the intrinsically safe power supply, and an a pole of the zener diode D1 is connected to the input terminal of the triggering unit.

The Zener diode D1 made of semiconductor is often operated in reverse breakdown state, and has the characteristic that the current is changed in a large range, but the voltage at two ends is basically unchanged. The voltage stabilizing unit of the circuit is connected with the output positive terminal of the intrinsic safety power supply through the K pole of a Zener diode D1, the A pole of the voltage stabilizing unit is connected with the input end of the trigger unit, when the reverse voltage between the K pole and the A pole of the Zener diode D1 reaches a certain value, the reverse current passes through the Zener diode D1 and flows through the trigger unit to the DGND end.

Furthermore, the trigger unit comprises a chip resistor R1 and a chip capacitor C1, wherein one end of the chip resistor R1 connected with the chip capacitor C1 in parallel is connected with the A pole of the Zener diode D1, and the other end of the chip resistor R1 connected with the output cathode of the intrinsic safety power supply. The current from the voltage stabilizing unit passes through the chip resistor R1, a voltage difference is formed at two ends of the chip resistor R1, when the voltage difference is large enough, the rear high-power protection unit can be triggered, and the front-end circuit is protected from being damaged by large current. The patch capacitor C1 is connected in parallel at two ends of the patch resistor R1, and plays a role in filtering noise waves.

Furthermore, the high-power protection unit comprises a chip resistor R2 and a silicon controlled SCR1, wherein one end of the chip resistor R2 is connected with the A pole of the Zener diode D1, and the other end of the chip resistor R2 is connected with the gate pole (namely the G pole) of the silicon controlled SCR 1; the A pole of the SCR1 is connected with the output positive pole terminal of the intrinsic safety power supply, and the K pole of the SCR1 is connected with the output negative pole of the intrinsic safety power supply.

The thyristor is a high-power electric element, it is a switch type semiconductor device, it can work under the condition of high voltage and strong current, it has the advantages of small volume, high efficiency and long service life, etc. The on-off state is determined by the control electrode G, and a certain voltage or current is applied to the control electrode G, so that the two ends of the controlled silicon A, K can be conducted. The G pole of the SCR1 in the high-power protection unit is connected with one end of a chip resistor R2, the other end of the chip resistor R2 is connected with the voltage output end of the trigger unit, the A pole of the SCR1 is connected with the output anode of the intrinsic safety power supply, and the K pole is connected with the ground DGND. The patch resistor R2 functions to limit current.

When the voltage output by the trigger unit reaches a certain value, the two ends of the A pole and the K pole of the SCR1 are triggered to be conducted to form a passage, at the moment, the two ends of the output anode and the output cathode of the mining intrinsically safe direct current stabilized power supply form a short circuit, the front mining intrinsically safe direct current stabilized power supply can cut off the power supply in time according to the short circuit condition, and short circuit protection is formed.

It should be noted that: when the silicon controlled rectifier is conducted, the current which can pass through the two ends of the A pole and the K pole can reach dozens of amperes, and in a circuit in practical application, because the output power of the front-end mining intrinsic safety type direct current stabilized voltage supply is limited, at the moment that the silicon controlled rectifier SCR1 is conducted, the two ends of the A pole and the K pole actually have only a few amperes through overcurrent and are completely within the bearable range of the silicon controlled SCR1, and the phenomenon that components are directly burned out to generate sparks due to overlarge short-circuit current can be avoided; at the moment when the SCR1 is switched on, the front-end mining intrinsically safe direct-current stabilized power supply can start overcurrent protection and cut off the power supply, so that the situation that the surface temperature exceeds a safe value due to the fact that the SCR1 bears short-circuit current for too long time and the coal mine underground safety accident is caused is avoided.

The innovative principle of the invention is as follows: the invention skillfully applies the controllable silicon in the voltage stabilizing circuit, when the voltage at two ends of the power supply does not exceed the voltage limit, the circuit is connected in parallel in the power supply circuit, and has no influence on the work of the power supply circuit; when the rear-stage voltage and the front-stage voltage are in short circuit in the power conversion circuit, or under the conditions of sudden voltage increase or voltage spike caused by short circuit of any two points in the circuit, the Zener diode D1 breaks down in the reverse direction, current flows through the Zener diode D1, voltage drop is formed through the chip resistor R1 of the trigger unit, and when the voltage drop reaches a certain value, the SCR1 is triggered to be conducted, so that the power circuit is in short circuit, the intrinsic safety power supply for supplying power to the front end is triggered to perform short circuit overcurrent protection, the power supply is cut off in time, and overvoltage protection is formed.

When the thyristor is conducted, the current which can pass through the A, K two ends is up to dozens of amperes, and in a circuit in practical application, because the output power of the front-end mining intrinsic safety type direct current stabilized voltage power supply is limited, at the moment that the thyristor SCR1 is conducted, the two ends of A, K are only a few amperes through overcurrent actually, the overcurrent is completely within the bearable range of the thyristor SCR1, and the spark caused by direct burning of components due to overlarge short-circuit current is avoided; at the moment of the conduction of the silicon controlled rectifier SCR1, the mining intrinsic safety type direct current stabilized voltage power supply at the front end can start overcurrent protection and cut off the power supply, so that the surface temperature of the silicon controlled rectifier SCR1 cannot exceed a safety value due to the fact that the silicon controlled rectifier SCR1 bears short-circuit heavy current for too long time, safety accidents under a coal mine are avoided, and overvoltage protection is formed. Compared with a common voltage stabilizing circuit, the explosion-proof safety performance of the mining electronic equipment can be improved by increasing the power value which can be borne by the common voltage stabilizing circuit and matching the voltage stabilizing circuit with the intrinsic safety power supply.

According to the specific embodiment, the circuit is simple in structural design, few in used components and controllable in production cost.

The invention is simple to apply, only the circuit is connected in parallel in the power circuit like a single voltage stabilizing diode, no influence is caused when the voltage of the power circuit is stable, and the voltage can be adjusted to be in a relatively stable state when the voltage of the circuit fluctuates slightly, so that the working requirement of the circuit is ensured. Any two points in the power circuit are short-circuited to cause that the voltage exceeds a limit value, and a rear-stage high-power protection unit can be triggered in time, so that the overcurrent protection of the front-stage intrinsic safety power supply is triggered to start, the power supply is turned off in time, overvoltage protection is formed, and the safety of the mining electronic equipment is improved.

The above description is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, several modifications and variations can be made without departing from the technical principle of the present invention, and these modifications and variations should also be regarded as the protection scope of the present invention.