KR20090047921A - Protection apparatus and method of overcurrent with thundervolt for electronic circuit - Google Patents

Abstract

The present invention relates to overcurrent protection combined with lightning protection of various electronic devices including communication devices.

Looking at the configuration of the present invention, an AC input power supply stage is a commercial AC power input to the device via a live stage and a neutral stage; A lightning protection module having a first protection means for blocking the lightning current flowing from the live stage and a third protection means for bypassing the lightning current to the neutral stage are connected to the AC input power terminal side in parallel. and; A second protection means connected to a live end between the lightning protection module and the line filter unit to block an overcurrent generated from a load circuit; The current blocking capacity of the second protective means is at least 2 to 7 times smaller than the current blocking capacity of the first protective means; And a current interruption capacity range of at least 1.1 to 16 times greater than the current flowing in the primary and secondary circuits in the load circuit at rated load. It is characterized by being set to.

The present invention can not only safely protect expensive precision devices from lightning, but also provide an effect of protecting the device by safely cutting off the overcurrent caused by abnormal operation of the load circuit.

 Lightning protection, overcurrent protection

Description

Overcurrent protection device with lightning protection and its method {PROTECTION APPARATUS AND METHOD OF OVERCURRENT WITH THUNDERVOLT FOR ELECTRONIC CIRCUIT}

The present invention relates to overcurrent protection combined with lightning protection of various electronic devices (hereinafter referred to as "devices") including communication devices, and more particularly, bypasses transient voltages safely when lightning enters the device. The present invention relates to a technology for safely blocking overcurrent caused by abnormal operation of a load circuit.

1 is a block diagram showing a circuit configuration for protecting a lightning strike of a conventional device.

Commercial AC power is supplied to the circuit of the device through the live terminal LT-1 and the neutral terminal NT-1 provided at the AC input power terminal V-in.

The live stage LT-1 includes a first protection device 12 formed of a fuse to cut off an overcurrent exceeding a predetermined value due to the inflow of lightning, and an output terminal of the first protection device 12; Connected between the neutral stage (NT-1), in response to the rise of the transient voltage due to the inflow of lightning including a surge (Surge) to reduce the self-resistance rapidly to reduce the transient current (NT-1) A third protection element 14 including a varistor that bypasses the circuit is provided.

In addition, at the rear end of the third protection element 14, the filtering of power noise introduced into the live stage LT-1 and the neutral stage NT-1 in parallel with the same, and the power circuit unit 40 to be described later A line filter unit 30 for preventing the switching current generated in the SMPS circuit provided in the back from the AC input power terminal (V-in) and a commercial AC input power supply circuit 50 It consists of a power supply circuit section 40 to convert the supply to a predetermined DC voltage according to the characteristics of ().

The power supply circuit section 40 includes a conventional bridge rectifier circuit (hereinafter referred to as a "rectifier circuit") and an AC component remaining in the DC component passed through the rectifier circuit in order to rectify the AC voltage to a DC voltage. In addition to a smoothing circuit for smoothing, a switching mode power supply (SMPS) circuit for generating multiple DC voltages suitable for the characteristics of the load circuit 50 is included.

In the conventional technology configured as described above, when the blocking current capacitance value of the first protection device 12 is set high for the purpose of protecting the lightning, the lightning current introduced into the live stage LT-1 of the device is the first protection device. Bypassing to the neutral stage NT-1 through the lightning current path I1 flowing along the paths of the 12 and the third protection element 14, the first circuit can be bypassed according to the abnormal operation of the load circuit 50. (1) Failure to properly cut off the overcurrent path (I2) flowing along the path of the protection element 12, the line filter unit 30, the power circuit unit 40, and the load circuit 50 of the device causes damage to the device. Such problems frequently occurred.

The present invention for solving the conventional problems as described above is to determine the current blocking capacity value of the element provided in the first protection means configured in the lightning protection module and the second protection means configured between the lightning protection module and the line filter unit. By adjusting to the ratio range of, it safely bypasses the transient voltage including surge caused by lightning inflow to the device and also cuts off the overcurrent due to abnormal operation of the load circuit. The purpose is to keep the devices safe.

As a means for solving the problems of the present invention as described above, an AC input power supply stage through which a commercial AC power is input to a circuit of a device via a live stage and a neutral stage is provided, and a live stage is provided on the AC input power supply side. It characterized in that the lightning protection module having a first protection means for blocking the lightning current flowing in from and the third protection means for integrally bypassing the lightning current to the neutral stage is connected in parallel.

In addition, a second protection means connected to the live stage between the lightning protection module and the line filter unit for blocking the over-current generated in the load circuit, wherein the current blocking capacity of the second protection means of the first protection means At least 2 to 7 times smaller capacity range than the current blocking capacity and at least 1.1 to 16 times larger current blocking capacity range for the current flowing in the primary and secondary circuits at rated load. do.

As another method for solving the problems of the present invention as described above, there is provided an AC power supply step of supplying a commercial AC power to the circuit of the device through the live stage and the neutral stage, the AC power is input to the device And converting into a DC voltage suitable for the characteristics of the load circuit of the device.

In addition, when the converted DC voltage is supplied to the circuit of the device, setting the current blocking capacity value of the second protection means by measuring the rated current flowing through the load circuit, and setting the current blocking capacity value of the second protection means In this case, setting the current blocking capacity value of the first protective means having a current blocking capacity range of at least 2 to 7 times larger than the current blocking capacity of the second protective means, and the current blocking capacity of the first protective means. Subsequent to the setting of the value, the setting of the current bypass capacitance value of the third protective means is provided.

Hereinafter, the objects and solutions to the present invention will become more apparent from the detailed description of the various embodiments shown in the accompanying drawings.

The present invention not only protects the devices from lightning by the lightning protection module and the second protection means provided at the AC input power terminal, but also blocks the overcurrent caused by the abnormal operation of the load circuit, thereby providing high precision and It provides the effect of protecting devices more securely.

In describing specific embodiments of the present invention, illustrated by the drawings of the present invention, the configuration and operation thereof will be described as at least one embodiment, whereby the technical spirit of the present invention and its core Configuration and actions are not limited.

For reference, in designating reference numerals in the drawings described in the present invention, it should be noted that the same components are given the same reference numerals as much as possible even if they are shown in different drawings.

Hereinafter, an overcurrent protection device and a method for lightning protection of a device of the present invention will be described in detail with reference to FIGS. 2 to 4.

Figure 2 is a block diagram showing a first embodiment of an overcurrent protection device with a lightning protection of the device according to the invention, Figure 3 is a second embodiment of an overcurrent protection device with a lightning protection of the device according to the present invention Block diagram.

The overall configuration according to the present invention is largely arranged, including the second protection means 200, the line filter unit 30, the power supply circuit unit, including the lightning protection module 100 from the AC input power supply terminal (V-in) side. 40, the load circuit 50 is configured.

The line filter unit 30 filters the power noise flowing into the neutral terminal NT-1 of the AC input power terminal V-in and switches generated in the SMPS circuit provided in the power circuit unit 40. It is provided to prevent the current from being returned to the AC input power terminal (V-in).

In addition, the power circuit unit 40 converts the commercial AC power supplied to the circuit of the device through the AC input power terminal (V-in) to a predetermined DC voltage in accordance with the characteristics of the load circuit 50. .

Of course, the power supply circuit unit 40 includes a conventional bridge rectifier circuit (hereinafter, referred to as a "rectifier circuit") for rectifying an AC voltage to a DC voltage, and an AC remaining in the DC component passed through the rectifier circuit. In addition to a smoothing circuit for smoothing the components, a switching mode power supply (SMPS) circuit for generating multiple DC voltages suitable for the characteristics of the load circuit 50 is included.

Next will be described in detail the core configuration and operation according to the present invention.

First, an AC input power terminal V-in through which a commercial AC power is input to a circuit of a device is provided through a live terminal LT-1 and a neutral terminal NT-1.

In addition, the AC input power terminal (V-in) side to the first protection means 102 and the lightning current for the blocking of the lightning current containing the surge (Surge) that exceeds the prescribed value flowing from the live terminal (LT-1) The lightning protection module 100 having the third protection means 104 for bypassing to the neutral stage NT-1 is connected in parallel.

The first protective means 102 and the third protective means 104 provided in the lightning protection module 100 are connected in series between the live stage LT-1 and the neutral stage NT-1. It may be preferable to configure the bypass circuit L1 to form the bypass path I1a of the lightning current.

In this case, the third protection means 104 rapidly decreases its resistance in response to the rise of the transient voltage due to the inflow of the lightning, and transmits the transient current including the surge through the bypass path I1a of the lightning current. It may be desirable to use a varistor that is a device that bypasses the neutral stage NT-1 of the differential circuit L1.

On the other hand, if the varistor provided in the third protection means 104 is doubled in thickness, two varistors of the same capacity are connected in series, and the protection voltage level is doubled, and the area of the varistor is also increased. When doubling, the two varistors of the same capacity are connected in parallel, so that the surge current capacity is doubled.

Therefore, it would be more desirable to select a device well suited to surge characteristics such as lightning strikes.

Here, the current bypass capacitance value of the third protection means 104 is selected to be at least 1.4 to 2.2 times the commercial AC voltage applied to the AC input power supply terminal (V-in) to operate at the lightning voltage. It would be desirable to.

For example, assuming that a commercial AC voltage applied to the AC input power supply terminal V-in is about 220V (volts), the third protection means 104 operates at least in the range of 380 to 484V (volts). By setting the current bypass operation, that is, bypass operation of the primary circuit L1 along the bypass path I1a of the lightning current, the damage of the secondary circuit L2 is prevented.

In other words, it is more preferable that the operating voltage of the third protection means 104 is designed to be about 470V (volt) at the commercial AC voltage of 220V (volt).

Of course, it is preferable that the third protection means 104 does not operate below the set voltage range but bypasses the set voltage range.

And, as shown in Figure 3 as another embodiment of the present invention may be configured to add a fourth protective means 106 in series with the third protective means (104).

Similarly, the lightning current I1a having passed through the third protection means 104 passes through the fourth protection means 106 once more, and partly along the lightning current bypass path I1a. Is bypassed, and the rest decreases below the withstand voltage, and thus does not affect the secondary circuit L2.

Of course, the third protection means 104 and the fourth protection means 106 maintains the off state when the transient voltage such as lightning strikes is not induced, thereby maintaining the AC input power supply terminal V-in. Normal power is supplied to the secondary circuit (L2) through.

In addition, it is connected to the live stage (LT-1) between the lightning protection module 100 and the line filter unit 30 is provided with a second protection means for blocking the over-current generated in the load circuit 50 do.

In addition, the first protection means 102 and the second protection means 200 provided in the lightning protection module 100 are connected in series to the live stage LT-1, and the line filter unit 30 and the power supply circuit unit. (40), the overcurrent blocking path (I2a) is formed through the load circuit (50).

The elements provided in the first protective means 102 and the second protective means 200 are constituted by a fuse that cuts off an overcurrent exceeding a predetermined value.

The first protection means 102 may be used as a means for preventing damage to the secondary circuit (L2) in the case of a malfunction due to a short circuit of the third protection means 104 or an increase in its resistance.

At this time, the current blocking capacity of the second protection means 200 is selected to be a capacity range of at least 2 to 7 times smaller than the current blocking capacity of the first protection means 102, but according to the characteristics of the load circuit 50 Considering the operation, it may be possible to select a 3 to 5 times smaller capacity range so that the interruption can be made more safely.

For example, assuming a lightning voltage induced by being induced directly or indirectly from the live stage LT-1 to be less than 7 kilovolts (kV), the current blocking capacity of the first protective means 102 is maximum 5A ( When set to amperes, the current interruption capacity of the second protection means 200 for protecting the load circuit 50 of the device may be set to about 1A (amps).

On the other hand, the current blocking capacity value of the second protective means 200 is at least 1.1 to 16 times more than the current flowing through the primary L1 and the secondary circuit L2 under the load circuit 50 at the rated load condition. It would be desirable to set a large current interruption capacitance range.

At this time, if the current blocking capacity range of the second protective means 200 is set to be lower than 1.1 times, the second protective means 200 is blocked even when the transient abnormality of the load circuit 50 does not occur. This can lead to a faulty or inconvenient case of stopping.

On the contrary, if the current blocking capacity range of the second protection means 200 is set higher than 16 times, the second protection means 200 is not cut off even though the transient abnormality of the load circuit 50 occurs. Cases that cause damage can occur.

In other words, on the condition that the load circuit 50 of the device operates normally, it is assumed that the current flowing in the primary L1 and the secondary circuit L2 is 0.1 A (amperes). It is more preferable to design the current interruption capacity of to about 1.0A (amperes), so that the overcurrent blocking operation can be performed.

Next, a method for protecting a device from lightning and overcurrent, which is another solution according to the present invention, will be described.

4 is an exemplary flowchart illustrating a process for protecting a device from lightning and overcurrent according to the present invention.

An AC power supply step S301 is provided in which commercial AC power is supplied to the circuit of the device through the live terminal LT-1 and the neutral terminal NT-1 of the AC input power terminal V-in.

When AC power is input to the device, a step (S302) of converting a DC voltage suitable for the characteristics of the load circuit 40 of the device is provided.

In this case, the conversion to the DC voltage smoothes the rectifier circuit for rectifying the AC voltage provided in the power circuit unit 40 to the DC voltage as described above, and the remaining AC component in the DC component passed through the rectifier circuit. In addition to the smoothing circuit, the switching mode power supply (SMPS) for generating a plurality of DC voltages suitable for the characteristics of the load circuit 50 is made.

When the converted DC voltage is supplied to the device, a step (S303) of measuring the rated current flowing through the load circuit 50 to set the current blocking capacity value of the second protection means 200 is provided.

At this time, if the current blocking capacity value of the second protective means 200 is set, as described above has a current blocking capacity range of at least 2 to 7 times larger than the current blocking capacity of the second protective means 200. A step S304 of setting the current interruption capacitance value of the first protective means 102 is provided.

As described above, the current blocking capacity of the second protection means 200 is at least equal to the current flowing in the primary L1 and the secondary circuit L2 under the rated load condition of the load circuit 50. It would be desirable to set a current interruption capacitance range of 1.1 to 16 times larger.

In addition, the first protection means 102 is characterized in that it is made in series with the third protection means 104 provided in the lightning protection module 100.

Subsequently, following the setting of the current blocking capacitance value of the first protective means 102, the process includes setting the current bypass capacitance value of the third protective means (S305).

On the other hand, it is preferable that the current bypass capacitance value of the third protection means 104 is set to be at least 1.4 to 2.2 times the input voltage applied through the AC input power supply terminal V-in.

For example, assuming that a commercial AC voltage applied to the AC input power supply terminal V-in is about 220V (volt), the third protection means 104 operates at a range of at least 380 to 484V (volt). By setting the current bypass operation, that is, bypass operation of the primary circuit L1 along the bypass path I1a of the lightning current, the damage of the secondary circuit L2 is prevented.

In other words, it is more preferable that the operating voltage of the third protection means 104 is designed to be about 470V (volt) at the commercial AC voltage of 220V (volt).

Similarly, it may be preferable that the third protection means 104 does not operate below the set voltage but bypasses the set voltage.

It will be apparent to those skilled in the art that various changes and modifications can be made without departing from the core technical spirit of the present invention through the above description.

Therefore, the technical scope of the present invention is not limited to the contents described in the various embodiments as mentioned, it will be desirable to be clearly defined by the claims of the present invention.

The overcurrent protection technology combined with lightning protection of the device according to the present invention can protect expensive precision devices from lightning and overcurrent at the same time, and thus is an invention of high industrial applicability that is expected to be expanded in the future in terms of applicability of the product. .

1 is a block diagram showing a circuit configuration for protecting a lightning strike of a conventional device.

2 is a block diagram showing a first embodiment of an overcurrent protection device that combines lightning protection of a device according to the present invention.

Figure 3 is a block diagram showing a second embodiment of the overcurrent protection device combined with the lightning protection of the device according to the present invention.

4 is an exemplary flowchart illustrating a process for protecting a device from lightning and overcurrent according to the present invention.

Explanation of symbols on the main parts of the drawings

LT-1: Live stage NT-1: Neutral stage

12: first protective element 14: second protective element

30: line filter unit 40: power supply circuit unit

50: load circuit 100: lightning protection module

102: first protective means 104: third protective means

200: second protective means

Claims (11)

AC input power stage through which the commercial AC power is input to the circuit of the device through the live stage and the neutral stage; A lightning protection module having a first protection means for blocking the lightning current flowing from the live stage and a third protection means for bypassing the lightning current to the neutral stage are connected to the AC input power terminal side in parallel. and; A second protection means connected to a live end between the lightning protection module and the line filter unit to block an overcurrent generated from a load circuit; The current blocking capacity of the second protective means is at least 2 to 7 times smaller than the current blocking capacity of the first protective means; And A current interruption capacity range of at least 1.1 to 16 times greater than the current flowing in the primary and secondary circuits in the load circuit at rated load; An overcurrent protection device as well as lightning protection, characterized in that configured to set to. According to claim 1, wherein the first and third protection means provided in the lightning protection module is connected in series between the live end and the neutral end; An over-current protection device as well as lightning protection for equipment, characterized by forming a bypass path for lightning current of the primary circuit. According to claim 1, The lightning protection module is connected in series between the live stage and the neutral stage by adding a fourth protection means to the first and third protection means provided in the protection means; An over-current protection device as well as lightning protection for equipment, characterized by forming a bypass path for lightning current of the primary circuit. The method of claim 1, wherein the first protective means and the second protective means are connected in series with a live end; An over-current protection device as well as lightning protection for a device, characterized in that it is formed by forming a blocking path of the over-current of the secondary circuit through the line filter unit, the power circuit unit, and the load circuit. 2. The device according to claim 1, wherein the elements provided in the first protective means and the second protective means are fuses which cut off at an overcurrent exceeding a predetermined value; The device provided in the third protective means includes a varistor; Overcurrent protection device combined with lightning protection of the device, characterized in that consisting of. 4. The overcurrent protection device as claimed in claim 3, wherein the device provided in the fourth protection means comprises an arrester. 6. The current bypass capacitance value of the third protection means is set to be at least 1.4 to 2.2 times the input voltage applied through the AC input power supply terminal. An overcurrent protection device that combines lightning protection with a device. AC power supply step of supplying commercial AC power to the circuit of the device through the live stage and the neutral stage; Converting an AC power source into a circuit of the device to a DC voltage suitable for the characteristics of the load circuit of the device; Setting the current cut-off capacity value of the second protection means by measuring the rated current flowing through the load circuit when the converted DC voltage is supplied to the circuit of the device; When the current blocking capacitance value of the second protection means is set, setting the current blocking capacitance value of the first protection means having a current blocking capacitance range of at least 2 to 7 times larger than the current blocking capacitance of the second protection means. step; Setting a current bypass capacitance value of the third protection means following the setting of the current blocking capacitance value of the first protection means; An overcurrent protection method as well as lightning protection of the device, characterized in that the process made. 9. A device according to claim 8, wherein the current interruption capacitance value of the second protective means is set at least 1.1 to 16 times the current flowing in the primary and secondary circuits under the rated load. Overcurrent protection with lightning protection. 9. The apparatus of claim 8, wherein the first protection means is connected in series with a third protection means provided in the lightning protection module;  An over-current protection method as well as lightning protection for a device, characterized by forming a bypass path for lightning current of a primary circuit. 11. The lightning protection of a device according to claim 8 or 10, wherein the current bypass capacitance value of the third protection means is set to be at least 1.4 to 2.2 times the input voltage applied through the AC input power terminal. Overcurrent protection method.

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