CN201478825U - Power supply overvoltage protection module of multi-gap metal gas discharge tube - Google Patents

Abstract

The utility model relates to a multi-gap metal ceramic gas discharge tube (hereinafter referred to as M-GDT) power supply overvoltage protection module, which mainly comprises the M-GDT. The end electrode A of the M-GDT is in conductive connection with a phase line L of a power supply, the end electrode A 'of the M-GDT is in conductive connection with a zero line N or a protected ground PE of the power supply, middle electrodes K1-Kn of the M-GDT are in conductive connection with one ends of voltage dependent resistors MOV 1-MOV N respectively, and the other ends of the MOV 1-MOV N are in conductive connection with the end electrode A or the end electrode A' of the M-GDT. The utility model discloses a product does not have potential safety hazard, through-flow capacity is big, do not have the afterflow, the reliability is high and stability is good.

Description

Multi-gap metal gas discharge tube power supply overvoltage protection module

technical field

The utility model relates to a power supply system overvoltage protection technology, in particular to a multi-gap metal gas discharge tube (hereinafter referred to as M-GDT) power supply overvoltage protection module.

Background technique

The power surge protector, also known as lightning arrester or surge protector, referred to as SPD (Surge Protection Device, surge protector), is composed of several overvoltage protection modules. Therefore, the performance of the power surge protector basically depends on the performance of the overvoltage protection module. At present, the overvoltage protection module of each power supply surge protector mainly adopts a piezoresistor (hereinafter referred to as MOV) with a thermal detachment alarm device ST or a series combination of an MOV with a thermal detachment alarm device ST and a single-gap gas discharge tube GDT.

The above-mentioned existing overvoltage protection module has the following disadvantages:

As shown in Figure 1, the MOV with thermal separation alarm device ST is directly used for overvoltage protection between the phase line L of the power supply and the neutral line N. When the lightning strike energy is too large, the MOV will burst, open circuit failure occurs, and the alarm cannot be activated, and an alarm is given Signal, so that the power supply is in an unprotected state, and the remaining lightning energy will damage the power supply equipment when it explodes; when the energy of the operating overvoltage of the power supply system is too large for MOV to consume, the MOV will break down and short circuit, because the energy provided by the power supply system is very Huge, the arc is formed quickly, and at this time, the release device ST cannot be quickly released, which may cause a fire.

As shown in Figure 2, when the MOV with the thermal separation alarm device ST is combined in series with the single-gap gas discharge tube GDT, it is directly used for the overvoltage protection of the power phase line L to the neutral line N, because the single-gap gas discharge tube GDT in series has a large flow energy And the existence of freewheeling, the above two situations will also appear. Because there is no other alternative, it is really helpless to use MOV to protect the overvoltage of the power system for more than 40 years.

Utility model content

The purpose of the utility model is to provide an M-GDT power supply overvoltage protection module to solve the shortcomings of the existing power supply lightning protectors such as potential safety hazards and freewheeling.

In order to achieve the above purpose, the M-GDT power supply overvoltage protection module of the utility model adopts the following technical scheme:

The M-GDT power supply overvoltage protection module of the utility model is mainly composed of M-GDT (that is, a multi-gap metal gas discharge tube). The terminal electrode A of the multi-gap metal gas discharge tube is conductively connected to the phase line L of the power supply, and the terminal electrode A' of the multi-gap metal gas discharge tube is conductively connected to the neutral line N (or protective ground PE) of the power supply; The gap metal gas discharge tube includes n intermediate electrodes K1~Kn, where n=1; the intermediate electrodes K1~Kn are electrically connected to the varistors MOV1~MOVn respectively, and the other ends of the varistors MOV1~MOVn are connected to the multi-gap metal The terminal electrode A or terminal electrode A' of the gas discharge tube is electrically conductively connected.

It should be pointed out that the size of n depends on the size of the power supply voltage (for example: 50Hz AC 220V rms takes n=4).

The above-mentioned technical scheme is further elaborated:

Three independent gaps are set between two adjacent electrodes of the M-GDT.

The terminal electrode A' of the M-GDT is equipped with a thermal detachment device ST, and the terminal electrode A' is connected to the neutral line N or the protective ground PE through the thermal detachment device ST; when the terminal electrode A' of the multi-gap metal gas discharge tube When the temperature reaches the detachment threshold, the thermal detachment device ST is detached from the terminal electrode A', thereby disconnecting the conductive connection between the terminal electrode A' and the neutral line N (or protective ground PE).

One side of the thermal detachment device is provided with a micro switch SW, and the micro switch SW is respectively associated with the warning light D and the remote signal interface E; the thermal detachment device ST is detached from the terminal electrode A' and starts simultaneously The micro switch SW outputs an alarm signal to the warning lamp D and the remote signaling interface E respectively when the micro switch SW is activated.

The multi-gap metal gas discharge tube power supply overvoltage protection module further includes a trigger circuit F, and the trigger circuit F is connected between the terminal electrode A and the terminal electrode A'.

The trigger circuit F includes a transformer T, a capacitor C3, a capacitor C4, and a switching device Q. One end of the primary winding of the transformer T is conductively connected to the end of the secondary winding through the capacitor C3, the switching device Q, and the other end of the primary winding of the transformer T One end is conductively connected to the same-named end of the secondary winding through the capacitor C4.

The switching device Q includes, but is not limited to: a gas discharge diode, a transient suppression diode, and a thyristor.

The multi-gap metal gas discharge tube power supply overvoltage protection module of the utility model has the following advantages:

Through the above technical scheme, the utility model has no potential safety hazard, large flow capacity, low residual voltage, no freewheeling, high reliability and good stability, and completely solves the problem of DC48V, AC50Hz 110V, 220V, 380V, 440V and other power supply systems. Protection against lightning strike overvoltage, operating overvoltage and electromagnetic pulse overvoltage.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description These are only some embodiments of the utility model, and those skilled in the art can also obtain other drawings according to these drawings without any creative effort.

FIG. 1 is a circuit diagram of an existing power supply overvoltage protection module;

FIG. 2 is a circuit diagram of another existing power supply overvoltage protection module;

Fig. 3 a is the circuit schematic diagram of the first embodiment of the utility model;

Fig. 3b is the equivalent circuit diagram of Fig. 3a;

Fig. 4a is the schematic circuit diagram of the second embodiment of the utility model;

Fig. 4b is the equivalent circuit diagram of Fig. 4a;

Fig. 5 is the schematic circuit diagram of the third embodiment of the utility model;

Fig. 6 is the schematic circuit diagram of the fourth embodiment of the utility model;

Fig. 7 is the circuit schematic diagram of the trigger circuit of the present utility model;

8, 9 and 10 are specific circuit diagrams of the trigger circuit of the present invention.

Detailed ways

In order to fully disclose the technical solution of the utility model, and those skilled in the art can realize the utility model, the utility model will be described in detail below in conjunction with the accompanying drawings.

It should be noted that the utility model adopts a new type of M-GDT, which includes at least one intermediate electrode between two terminal electrodes of the M-GDT, and three independent gaps are provided between two adjacent electrodes of the M-GDT.

Referring to Fig. 3a, it is a schematic circuit diagram of the first embodiment of the present utility model. The M-GDT power supply overvoltage protection module in this embodiment is mainly composed of M-GDT. The terminal electrode A of the M-GDT is conductively connected to the phase line L of the power supply, the terminal electrode A' of the M-GDT is conductively connected to the neutral line N of the power supply or the protective ground PE, and the middle electrodes K1-Kn of the M-GDT are respectively connected to One ends of MOV1-MOVn are conductively connected, and the other ends of MOV1-MOVn are conductively connected to the terminal electrode A' of the M-GDT.

More specifically, the terminal electrode A' of the M-GDT is equipped with a thermal disconnection device ST, and the terminal electrode A' is connected to the neutral line N or the protective ground PE through the thermal disconnection device ST; when the terminal electrode A of the M-GDT When the temperature of ' reaches the detachment threshold, the thermal detachment device ST is detached from the terminal electrode A', thereby disconnecting the conductive connection between the terminal electrode A' and the neutral line N (or protective ground PE). At the same time, one side of the thermal detachment device ST is provided with a micro switch SW, and when the thermal detachment device ST is detached from the terminal electrode A', the micro switch SW is activated at the same time, and the micro switch SW is connected to the warning light D and the remote signaling interface respectively. E is associated, and when the micro switch SW is activated, an alarm signal is output to the alarm light D and the remote signaling interface E respectively.

See Figure 3b, which is the equivalent circuit diagram of Figure 3a, and its working principle is as follows: When the circuit in Figure 3a is not working, M-GDT is equivalent to n capacitors C1 with equal capacitance in series, and MOV1~MOVn is equivalent to n A capacitor C2 with the same capacitance value, where C2 is much larger than C1. When the pulse overvoltage invades between the power supply L-N, due to the voltage division effect of the capacitor, the A-K1 gap is pre-conducted through MOV1, and the voltage between L-N is clamped by MOV1 in a short time after the A-K1 gap is turned on. The arc voltage decreases, and the voltage on MOV1 will start the gaps of K1-K2, K2-K3, K3-K4, ..., Kn-A' in sequence. After the gap of Kn-A' is turned on, the whole M-GDT is turned on, and the whole M -After the GDT is turned on, because the voltage of the arc discharge of the M-GDT between A-A' is lower than the varistor voltage of MOV1~MOVn, MOV1~MOVn stop working, and all the overcurrent flows through the M-GDT. After the pulse overvoltage, because the peak voltage of the power supply is lower than the voltage for maintaining the arc discharge of the M-GDT, the M-GDT stops working and extinguishes the arc, and returns to a non-conductive state.

Referring to Fig. 4a is a schematic circuit diagram of the second embodiment of the present invention. The difference between this embodiment and the first embodiment is that the other ends of the MOV1-MOVn that are electrically connected to the M-GDT are electrically connected to the terminal electrode A of the M-GDT, and the working principle is the same as that of the first embodiment, A '-K1, K1-K2, K2-K3, K3-K4, ..., Kn-A are turned on in sequence.

Specifically, as shown in Figure 4a, the M-GDT in this embodiment includes intermediate electrodes K1~Kn, and the intermediate electrodes K1~Kn are electrically connected to MOV1~MOVn respectively, and the other ends of MOV1~MOVn are connected to the M-GDT. Terminal A is connected. At the same time, a thermal detachment device ST is installed on the terminal electrode A' of the M-GDT, and when the temperature of the terminal electrode A' of the M-GDT reaches the detachment threshold, the thermal detachment device ST is detached from the terminal electrode A' , so as to disconnect the conductive connection between the terminal electrode A' and the neutral line N (or protective ground PE), such as to achieve the purpose of protecting subsequent electrical equipment.

One side of the thermal detachment device ST as shown in Figure 3b and 4b is provided with a micro switch SW, the micro switch SW is respectively associated with the warning light D and the remote signal interface E, and the thermal detachment device ST is detached from the terminal electrode A' At the same time, the micro switch SW is started, and when the micro switch SW is started, an alarm signal is output to the warning light D and the remote signaling interface E respectively. In a specific implementation, the thermal detachment device ST may be a spring piece, and one end of the spring piece is welded to the terminal electrode A' of the multi-gap cermet gas discharge tube with low-temperature solder (such as tin). When the temperature of the terminal electrode A' of the multi-gap cermet gas discharge tube reaches the melting point of the solder, the spring piece is separated from the terminal electrode A' of the multi-gap cermet gas discharge tube. When the spring piece is disengaged from A', the micro switch SW is pressed to activate the micro switch SW. After the micro switch SW is activated, the alarm signal is respectively output to the warning light D and the remote signaling interface E, the warning light D turns from green to red, and the remote signaling interface E sends the warning signal to the remote monitoring system.

It should be noted that the thermal detachment device ST and the micro switch SW are linked. Before the ST is detached from A', SW1-1 is closed, SW1-2 is disconnected, the green indicator LED1 is on, and SW2-1 is closed, and SW2-2 is disconnected. , the remote signaling interface E has no signal output; after ST is separated from A', SW1-1 is disconnected, SW1-2 is closed, the red indicator LED2 is on, SW2-1 is disconnected, SW3-2 is closed, and the remote signaling interface E has signal output .

The discharge tube in the utility model adopts a multi-gap cermet gas discharge tube, which is equivalent to a plurality of discharge tubes used in series, and the gaps A-K1, K1-K2, ..., Kn-A' (or A' -K1, K1-K2, ..., Kn-A) are turned on sequentially, and the limiting voltage is equivalent to the pulse breakdown voltage between the electrodes of A-K1, so the residual voltage is quite low. At the same time, after the overvoltage, the M-GDT quickly returns to the non-conducting state without freewheeling, thereby improving the reliability, stability and safety of the overvoltage protection module of the multi-gap metal gas discharge tube power supply. At the same time, the terminal electrode A' of the M-GDT is equipped with a thermal detachment device SW, the purpose of which is to further improve the safety of the overvoltage protection module of the multi-gap metal gas discharge tube power supply, so as to avoid unexpected adverse consequences, such as fire. Devices such as the micro switch SW, the remote signaling interface E, and the warning light D allow the staff to detect abnormalities in the overvoltage protection module in time and repair them in time to avoid damage to subsequent electrical equipment.

Referring to FIG. 5 , it is a schematic circuit diagram of the third embodiment of the present invention. This embodiment adds a trigger circuit F on the basis of the first embodiment. The trigger circuit F is connected between the A terminal and the A' terminal of the multi-gap metal gas discharge tube, wherein the G terminal of the trigger circuit F is electrically connected to the A terminal, and the H terminal is electrically connected to the A' terminal.

As shown in FIG. 7 , it is a schematic circuit diagram of the trigger circuit F. The trigger circuit F includes a transformer T, a capacitor C3, a capacitor C4, and a switching device Q. One end of the primary winding of the transformer T is conductively connected to the same-named end of the secondary winding through the capacitor C3 and the switching device Q, and the other end of the primary winding of the transformer T is connected through a Capacitor C4 is conductively connected to the same terminal of the secondary winding. When the overvoltage invades between A-A', before the M-GDT is turned on or even before the A-K1 (A'-K1) gap is turned on, the overvoltage first passes through the switching device Q, the capacitor C3, and the transformer T The secondary winding is turned on, thereby increasing the corresponding speed of the overvoltage protection module. At the same time, its limiting voltage is equivalent to the breakdown voltage of the switching device Q, so that the residual voltage can be further reduced to prevent the residual voltage from damaging subsequent electrical equipment.

In a specific implementation, the switching element Q may be: a gas discharge diode, a transient suppression diode, a thyristor, or other switching devices. As shown in FIG. 8, the switching element Q is a gas discharge diode GDT; as shown in FIG. 9, the switching element Q is a transient suppression diode TVS; as shown in FIG. 10, the switching element Q is a thyristor SCR.

Referring to FIG. 6 , it is a schematic circuit diagram of the fourth embodiment of the present utility model. This embodiment adds a starting circuit F on the basis of the second embodiment. The trigger circuit F is connected between the A terminal and the A' terminal of the multi-gap metal gas discharge tube, wherein the G terminal of the trigger circuit F is electrically connected to the A terminal, and the H terminal is electrically connected to the A' terminal.

The trigger circuit F of this embodiment has the same internal circuit as the trigger circuit F of the third embodiment, has the same working principle, and has the same beneficial effects, so the description will not be repeated here.

The multi-gap cermet gas discharge tube power supply overvoltage protection module of the utility model reduces fire safety hazards, has low residual voltage, no continuous current, high reliability and good stability, and can protect subsequent electrical equipment from overvoltage to the greatest extent. damage.

The above is a preferred embodiment of the present utility model, it should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present utility model, some improvements and modifications can also be made, these improvements and modifications It is also regarded as the protection scope of the present utility model.

The above is a preferred embodiment of the present utility model, it should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present utility model, some improvements and modifications can also be made, these improvements and modifications It is also regarded as the protection scope of the present utility model.

Claims (7)

1. The multi-gap metal gas discharge tube power supply overvoltage protection module is characterized in that: it is mainly composed of a multi-gap metal gas discharge tube, and the terminal electrode (A) of the multi-gap metal gas discharge tube is connected to the phase line (L) of the power supply Conductive connection, the terminal electrode (A') of the multi-gap metal gas discharge tube is conductively connected with the zero line (N) or protective ground (PE) of the power supply; the multi-gap metal gas discharge tube includes n intermediate electrodes (K1～Kn ), wherein n≥1; the intermediate electrodes (K1～Kn) are electrically connected to the piezoresistors (MOV1～MOVn) respectively, and the other end of the piezoresistors (MOV1～MOVn) is connected to the terminal electrode of the multi-gap metal gas discharge tube (A) or terminal electrodes (A') are electrically connected. 2 . The multi-gap metal gas discharge tube power supply overvoltage protection module according to claim 1 , wherein three independent gaps are provided between two adjacent electrodes of the multi-gap metal gas discharge tube. 3 . 3. The multi-gap metal gas discharge tube power supply overvoltage protection module according to claim 1 or 2, characterized in that: the terminal electrode (A') of the multi-gap metal gas discharge tube is equipped with a thermal detachment device (ST) , the terminal electrode (A') is connected to the neutral line (N) or the protective ground (PE) through the thermal detachment device (ST); when the temperature of the terminal electrode (A') of the multi-gap metal gas discharge tube reaches the detachment threshold , the thermal disconnection device (ST) is detached from the terminal electrode (A'), thereby disconnecting the conductive connection between the terminal electrode (A') and the neutral line (N) or the protective earth (PE). 4. multi-gap metal gas discharge tube power supply overvoltage protection module as claimed in claim 3, is characterized in that: One side of the thermal detachment device is provided with a micro switch (SW), and the micro switch (SW) is respectively associated with the warning light (D) and the remote signal interface (E); The thermal detachment device (ST) detaches from the terminal electrode (A') and activates the micro switch (SW) at the same time, and when the micro switch (SW) is activated, outputs warning signal. 5. multi-gap metal gas discharge tube power supply overvoltage protection module as claimed in claim 3, is characterized in that: The multi-gap metal gas discharge tube power supply overvoltage protection module also includes a trigger circuit (F), and the trigger circuit (F) is connected between the terminal electrode (A) and the terminal electrode (A'). 6. multi-gap metal gas discharge tube power supply overvoltage protection module as claimed in claim 5, is characterized in that: The trigger circuit (F) includes a transformer (T), a capacitor (C3), a capacitor (C4), and a switching device (Q). One end of the primary winding of the transformer (T) passes through the capacitor (C3), the switching device (Q) It is conductively connected with the terminal of the same name of the secondary winding, and the other end of the primary winding of the transformer (T) is conductively connected with the terminal of the same name of the secondary winding through the capacitor (C4). 7. The multi-gap metal gas discharge tube power supply overvoltage protection module as claimed in claim 6, characterized in that: The switching device (Q) includes but not limited to: a gas discharge diode, a transient suppression diode, and a thyristor.

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