KR100572466B1 - High resistance grounding device - Google Patents

Abstract

The present invention; The present invention relates to a high resistance grounding device that enables continuous operation of the system while maintaining the instantaneous overvoltage protection of the grounding system in case of a ground fault.

The present invention as such; A housing 10; A high resistance unit 20 composed of a plurality of high resistances GRES to offset the instantaneous overcurrent to a minimum current value when a ground fault occurs; A transformer unit 30 for converting a rated voltage into a commercial voltage (110V / 220V); A power pushbutton 40 for turning the power on and off; A meta relay 50 that operates as an overcurrent flows into the high resistance unit 20; A ground fault relay 60 for detecting ground faults; An alarm and pulse generating means 70 for generating an alarm when the meta relay 50 is driven and displaying a ground fault situation to the operator and generating a pulse according to the operator's selection; And buzzer generating means 80 for generating an alarm and a buzzer when a ground fault is detected through the ground fault relay 60.

According to the invention; It maintains the instantaneous overvoltage protection function of the grounding system in a state where the transformer or generator can be continuously operated in case of a ground fault, thereby preventing the enormous loss of the system and human injury caused by sudden power failure, ignition risk and fire. Excellent effect.

High resistance grounding device, meta relay, transformer or generator neutral point (N),

Description

High Resistance Ground Device {HIGH RESISTANCE GROUNDING DEVICE}             

1 is a front view showing the appearance of a high resistance grounding apparatus according to an embodiment of the present invention,

2 is a right side cross-sectional view of the high resistance grounding apparatus according to FIG. 1;

3 is a circuit diagram illustrating an internal configuration of the high resistance grounding apparatus according to FIG. 1.

<Explanation of symbols for the main parts of the drawings>

10 housing 20 high resistance part

30: transformer 40: power push button

50: meta relay 60: ground fault relay

70: alarm and pulse generating means 71: green lamp

72: red lamp 73: MR switch

74: Green Lamp Test Button 75: Red Lamp Test Button

76: first alarm 77: select switch

78: pulse generator 80: buzzer generating means

81: ground fault relay 82: second alarm

83: buzzer selection switch 84: buzzer generator

85: buzzer button 90: voltage transducer

100: voltage meter 110: current transducer

120: current meter 130: temperature sensor

140: fan 150: limit switch

160: Lamp 170: Fan / lamp pushbutton

180: test switch

The present invention relates to a high resistance grounding device, and more particularly, is installed between the neutral point (N) of the transformer or generator in the industrial site and the ground, the moment of the grounding system in a state in which the continuous operation of the transformer or generator is possible in the event of a ground fault The present invention relates to a high-resistance grounding device that maintains overvoltage protection to proactively prevent enormous loss of the system due to sudden power outages, ignition hazards and fires.

As is well known, industrial sites are using grounding devices in transformers or generators to prevent damage to the system and human damage from ground faults. Earlier, the three-phase four-wire power supply system in the industrial field adopted a delta (Δ) ungrounded method to prevent damage to the system and human damage caused by ground faults. However, in the non-grounding method, many motors or busbars are frequently burned out at a time, and as a result of analyzing the problems of the non-grounding method, the overground due to arcing or resonance ground fault is over. It was found that the cause was over voltage.

Therefore, most industrial sites at home and abroad have adopted a direct grounding method in order to overcome the problems of the non-grounding method described above. However, the conventional direct grounding method can overcome the problems of the non-grounding method, which is the above-described delta (Δ) method, but the system loses enormous loss and lifespan due to sudden power failure, ignition risk and fire due to large current during ground fault. The damage could not be overcome. In particular, in industrial sites such as oil refineries, chemical plants, paper mills, textile factories, semiconductor factories, and LNG takeover bases, if the system stops operating due to a sudden power outage during a ground fault, fatal property damage may occur due to the characteristics of the produced product. According to the conventional direct grounding method described above, there is a problem in that such property damage cannot be overcome at all.

Accordingly, the present invention has been made to solve the conventional problems as described above, the object of the present invention is to maintain the instantaneous overvoltage protection of the grounding system in a state in which the continuous operation of the transformer or generator in the event of a ground fault, It is to provide a high resistance grounding device to prevent the enormous loss of life and damage to the system due to power failure, fire hazard and fire.

Another object is to provide a high-resistance grounding device for promptly notifying the operator of such an emergency in the event of an initial ground fault, and for allowing the operator to easily find the point of failure due to the ground fault.

In order to achieve the above object, the high resistance grounding device of the present invention is installed between the neutral point (N) of the transformer or generator of the system and the ground in the grounding device to prevent damage to the system in the event of a ground fault,

A housing having a rectangular stand shape in which a door is installed at the front side;

Mounted inside the housing, and installed between the neutral point (N) of the transformer or generator and the ground, and composed of a plurality of high resistance connected in series or in parallel, if the instantaneous overcurrent occurs due to the ground fault to the minimum current value High resistance to cancel;

A transformer unit mounted inside the housing to receive a rated voltage from a neutral point N of a transformer or a generator and convert the rated voltage into a commercial voltage (110V / 220V);

It is installed in the front part of the housing, and is connected between the neutral point (N) of the transformer or generator and the transformer part, and connect or short-circuit the neutral point (N) of the transformer or generator and the transformer part according to the operator's pressing operation. Power pushbutton;

A meta relay installed on the front part of the housing and operating as an overcurrent flows to the high resistance part;                         

A ground fault relay mounted between the high resistance portion and the ground to detect ground fault;

It is installed inside the housing and is driven by a commercial voltage (110V / 220V) supplied from the transformer, and when the meta relay is driven as a ground fault occurs, an alarm is generated and a ground fault situation is displayed to the operator. Alarm and pulse generating means for generating a pulse for detecting a failure point at a predetermined interval to a transformer or a generator of the system according to an operator's selection; And

A buzzer installed inside the housing and driven by a commercial voltage (110V / 220V) supplied from the transformer, and when a ground fault is detected through the ground fault relay, a buzzer is generated for a predetermined time while generating an alarm. It is characterized by consisting of the generating means.

Hereinafter, a high resistance grounding apparatus according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a front view showing the appearance of a high resistance grounding apparatus according to an embodiment of the present invention, Figure 2 is a cross-sectional view of the right side of the high resistance grounding apparatus according to an embodiment of the present invention, Figure 3 is an embodiment of the present invention As a circuit diagram showing the internal structure of a high resistance grounding apparatus according to an example, the high resistance grounding apparatus according to an embodiment of the present invention includes a housing 10, a high resistance portion 20, and a transformer 30. , Power Push Button (40), Meta Relay (50), Ground Relay (60), Alarm and Pulse Generator (70), Buzzer Generator (80), Voltage Transducer (90) ), Voltage meter (Voltage Meter) (100), current transducer (110), current meter (Current Meter) (120), temperature sensor unit (130), fan (FAN) (140), limit switch (150), The lamp 160 includes a lamp 160, a fan / lamp push button 170, and a test switch 180.

The housing 10 serves to protect the above-described parts 20 to 180 in a rectangular stand shape in which a door 11 is installed at a front side as shown in FIGS. 1 and 2.

배의 전압이므로, 이러한 순간 과전류를 "0.1∼0.8A"의 최소치 전류까지 상쇄시키기 위해서는 상기 고저항부(20)의 다수개의 고저항(GRES)을 "159∼332Ω"의 범위 내에서 직렬 또는 병렬로 적절하게 접속시켜야 한다.In addition, the high resistance portion 20 is mounted inside the housing 10, and is installed between the neutral point (N) of the transformer or generator of the system (not shown) and the ground, and connected in a series or parallel manner It consists of a resistor (GRES), and if the instantaneous overcurrent occurs due to the ground fault to offset the minimum current value serves to protect the transformer or generator of the system. At this time, the range of the minimum current value canceled by the high resistance section 20 is "0.1 to 0.8 A". Therefore, the rated voltage applied to the neutral point N of the transformer or generator of the system is "220 to 460V" of a three-phase four-wire type, and the instantaneous overvoltage applied to the high resistance section 20 as a ground fault occurs is rated voltage. of

Since the voltage is doubled, in order to cancel such instantaneous overcurrent to the minimum current of "0.1 to 0.8 A", a plurality of high resistances GRES of the high resistance section 20 are series or parallel within the range of "159 to 332 Ω". Must be properly connected.

On the other hand, the transformer 30 is mounted inside the housing 10, and serves to convert the commercial voltage (110V / 220V) by receiving a rated voltage from the neutral point (N) of the transformer or generator.

In addition, the power push button 40 is installed at any position of the housing 10, is connected between the neutral point (N) of the transformer or generator and the transformer 30, according to the operator's pressing operation The neutral point N of the transformer or generator and the transformer 30 are connected to or short-circuited.

On the other hand, the meter relay (MR) (50) is a relay that is installed in the front portion of the housing 10, as shown in Figure 1, and operates as the overcurrent flows to the high resistance portion (20).

In addition, the ground relay 60 is mounted between the high resistance portion 20 and the ground, and serves to detect when a ground fault occurs.

On the other hand, the alarm and pulse generating means 70 is installed in the housing 10, is driven by the commercial voltage (110V / 220V) supplied from the transformer 30, the ground fault occurs as When the meta relay 50 is driven, an alarm is generated and a ground fault is displayed to the operator, and a pulse for detecting a bad point is generated to the transformer or generator of the system at regular intervals according to the operator's selection. 3, the green lamp 71, the red lamp 72, the MR relay switch 73, the green lamp test button 74, the red lamp test button 75, and the like. A first alarm 76, a select switch 77, and a pulse generator 78 are provided.

At this time, the green lamp 71 of the alarm and pulse generating means 70 is a lamp which is installed at any position of the housing 10, and displays a normal state to the operator.

In addition, the red lamp 72 of the alarm and pulse generating means 70 is a lamp which is installed at any position of the housing 10, to indicate to the operator a dangerous state in the event of a ground fault.

On the other hand, the MR switch 73 of the alarm and pulse generating means 70 is connected between the transformer 30 and the green / red lamps 71 and 72, the transformer 30 in the normal state Turns on the green lamp 71 by shorting the contact b between the green lamp 71 and the meta relay 50 when the ground fault occurs, disconnecting the b contact and disconnecting the transformer 30 from the transformer 30. The a contact between the red lamps 72 is short-circuited to turn off the green lamps 71 and to light up the red lamps 72.

In addition, the green lamp test button 74 of the alarm and pulse generating means 70 is installed on the front portion of the housing 10 as shown in Figure 1, between the MR switch 73 and the green lamp 71 It is connected to the test button for testing the lighting state of the green lamp 71 in accordance with the operator's pressing operation.

On the other hand, the red lamp test button 75 of the alarm and pulse generating means 70 is installed on the front of the housing 10, as shown in Figure 1, between the MR switch 73 and the red lamp 72 It is connected to the test button for testing the lighting state of the red lamp 72 in accordance with the operator's pressing operation.

Further, the first alarm 76 of the alarm and pulse generating means 70 is connected to the contact a of the MR switch 73 and to the timer TR (SET: 5 sec, RANGE: 0 to 10 sec). For example, when the red lamp 72 is turned on, it serves to generate an alarm to the operator for a predetermined time.

On the other hand, the select switch 77 of the alarm and pulse generating means 70 is installed in the front portion of the housing 10 as shown in Figure 1, is connected to the a contact of the MR switch 73, the operator's selection This switch selects the pulse generation mode.

In addition, the pulse generator 78 of the alarm and pulse generating means 70 is composed of a pulse contactor (PC) and a pulse contactor relay (PCR), the select switch 77 When the pulse generation mode is selected through, it generates a pulse for detecting a defective point at a predetermined interval (SET: 0.75 sec, 40 pulse / 1 min) to generate a transformer or a generator of the system. Therefore, the operator can find the ground fault line through the pulse output from the pulse generator 78 by using a current detector (Current Detector).

On the other hand, the buzzer generating means 80 is installed in the housing 10, is driven by the commercial voltage (110V / 220V) supplied from the transformer 30, through the ground fault relay 60 When a ground fault is detected, it generates an alarm and at the same time generates a buzzer, which is a ground fault relay 81, a second alarm 82, a buzzer selection switch 83, as shown in FIG. The buzzer generating part 84 and the buzzer stop button 85 are comprised.

At this time, the ground relay 81 of the buzzer generating means 80 is a relay driven as a ground fault is detected through the ground relay 60.

In addition, the second alarm 82 of the buzzer generating means 80 is connected to the ground fault relay 81, and serves to generate an alarm to the operator when the ground fault relay 81 is driven.

On the other hand, the buzzer selection switch 83 of the buzzer generating means 80 is installed on the front of the housing 10, as shown in Figure 1, connected between the ground fault relay 81 and the buzzer generating unit 84 In the normal state, the switch turns on the buzzer function according to the operator's selection.

The buzzer generating unit 84 of the buzzer generating means 80 is connected to the ground fault relay 81, and is composed of a buzzer BZ and a buzzer timer (BZT), and the ground relay 81 is driven. At the same time, if the buzzer selection switch 83 is on, it serves to generate a buzzer for a predetermined time.

In addition, the buzzer stop button 85 of the buzzer generating means 80 is installed in the front portion of the housing 10, as shown in Figure 1, connected between the ground fault relay 81 and the buzzer generating portion 83 As a result, the power to the buzzer generating unit 84 is cut off according to the operator's pressing operation to stop the buzzer BZ.

On the other hand, the voltage transducer 90 serves to measure the voltage at both ends of the high resistance unit 20, the voltage meter 100 is installed on the front of the housing 10 as shown in FIG. It is a meter that displays the voltage across the high resistance portion 20 measured by the transducer 90 to the operator.

In addition, the current transducer 110 is mounted between the high resistance section 20 and the ground to measure the rated current flowing in the high resistance section 20 when the ground fault, the current meter 120 is As shown in FIG. 1, the meter is installed on the front of the housing 10 to display a rated current value measured by the current transducer 110 to an operator.

On the other hand, the temperature sensor 130 detects when the internal temperature of the housing 10 rises above a predetermined temperature due to overheating of the high resistance unit 20 and outputs a temperature rise detection signal to the fan 140. The fan 140 is installed at the rear of the housing 10 as shown in FIG. 2 to drive when the temperature rise detection signal is input from the temperature sensor unit 130 to drive the internal temperature of the housing 10. After cooling down, the temperature stops below a certain temperature.

In addition, the limit switch 150 is installed in the door 11 of the housing 10 to detect whether the door 11 is opened or closed, the lamp 160 is the front portion of the housing 10 Is installed in the on / off (ON / OFF) of the limit switch 150 is turned on or off, and serves to display the opening and closing state of the door 11 to the operator.

In addition, the fan / lamp pushbutton 170 is installed at an arbitrary position of the housing 10, and is connected between the fan 140 and the lamp 160 and the transformer 30, and pressed by an operator. According to the operation, the fan 140, the lamp 160, and the transformer 30 are connected or short-circuited.

On the other hand, the test switch 180 is installed on the front portion of the housing 10 as shown in Figure 1, the connection point (c) between the high resistance portion 20 and the ground and the neutral point (N) of the transformer or generator Connected between the power pushbuttons 40, and when turned on according to the operator's selection, the rated voltage applied to the neutral point N of the transformer or generator is switched to flow to the high resistance section 20 so that the meta relay It is a switch for driving 50.

Next, an operation process of the high resistance grounding device according to the exemplary embodiment of the present invention having the above configuration will be described with reference to FIG. 3.

First, the operator presses the power push button 40 to turn on the power. Then, the transformer unit 30 receives a rated voltage (“220 to 460 V” of a three-phase four-wire type) from the neutral point N of the transformer or generator and converts it into a commercial voltage (110 V / 220 V) and supplies it to each circuit. do.

Then, the operator turns on the fan / lamp pushbutton 170 and the buzzer selection switch 83 in turn. At this time, in the normal state in which no ground fault occurs, there is no change in the meta relay 50, and as the b contact of the MR switch 73 is turned on, the green lamp of the alarm and pulse generating means 70 is turned on. 71 is lit, and the select switch 77 is also positioned in a normal state.

On the other hand, if a ground fault occurs in this situation, the high resistance unit 20 protects the transformer or generator of the system by offsetting the instantaneous overcurrent generated by the ground fault to a minimum current value within the range of "0.1 ~ 0.8A". At this time, the meta relay 50 is driven, and at the same time, the ground fault relay 60 detects a ground fault condition. In such a situation, the voltage meter 100 and the current meter 120 display the instantaneous overvoltage and overcurrent flowing in the high resistance section 20 to the operator.

As described above, when the meta relay 50 is driven in response to a ground fault, the MR switch 73 disconnects the b contact and shorts the a contact between the transformer 30 and the red lamp 72 so that the green The lamp 71 is turned off and the red lamp 72 is turned on, so that power is supplied to the first alarm 76 to generate an alarm to the operator for a predetermined time.

In addition, when the ground relay 81 is driven as a ground fault is detected through the ground relay 60, the second alarm 82 and the buzzer generator 84 are supplied with power to alert the operator for a predetermined time. And generates a buzzer. At this time, when the operator hears the buzzer and presses the buzzer stop button 85, the buzzer BZ of the buzzer generating unit 84 is stopped.

On the other hand, after the operator hears the alarm and the buzzer sound according to the ground, and turns on the select switch 77 of the alarm and the pulse generating means 70, the pulse generator 78 generates a pulse for detecting the defective point at a predetermined interval (SET: 0.75sec, 40pulse / 1min) generated by the transformer or generator of the system. As a result, the operator can find the ground fault line through the pulse output from the pulse generator 78 using a current detector while the system is in operation.

Although the present invention has been described in more detail with reference to some embodiments, the present invention is not necessarily limited to these embodiments, and various modifications can be made without departing from the spirit of the present invention.

As described above, according to the high-resistance grounding device according to the present invention, the momentary voltage protection function of the grounding system is maintained in a state in which a continuous operation of a transformer or a generator is possible in case of a ground fault. It's a great way to help prevent profound loss and human damage to your system.

In addition, according to the present invention there is an excellent effect that allows the operator to quickly respond to the emergency situation caused by the ground fault by promptly notifying the operator of such an emergency situation.

In addition, according to the present invention by providing a current pulsing (Pulsing) method in the continuous operation state of the ground fault system, allowing the operator to find the fault point caused by the ground fault accurately and easily to enable easy maintenance Excellent effect.

Claims (7)

In the grounding device is installed between the neutral point (N) of the transformer or generator of the system and the ground to prevent damage to the system in the event of a ground fault, A housing having a rectangular stand shape in which a door is installed at the front side; Mounted inside the housing, and installed between the neutral point (N) of the transformer or generator and the ground, and composed of a plurality of high resistance connected in series or in parallel, if the instantaneous overcurrent occurs due to the ground fault to the minimum current value High resistance to cancel; A transformer unit mounted inside the housing to receive a rated voltage from a neutral point N of a transformer or a generator and convert the rated voltage into a commercial voltage (110V / 220V); It is installed in the front part of the housing, and is connected between the neutral point (N) of the transformer or generator and the transformer part, and connect or short-circuit the neutral point (N) of the transformer or generator and the transformer part according to the operator's pressing operation. Power pushbutton; A meta relay installed on the front part of the housing and operating as an overcurrent flows to the high resistance part; A ground fault relay mounted between the high resistance portion and the ground to detect ground fault; It is installed inside the housing and is driven by a commercial voltage (110V / 220V) supplied from the transformer, and when the meta relay is driven as a ground fault occurs, an alarm is generated and a ground fault situation is displayed to the operator. Alarm and pulse generating means for generating a pulse for detecting a failure point at a predetermined interval to a transformer or a generator of the system according to an operator's selection; And A buzzer installed inside the housing and driven by a commercial voltage (110V / 220V) supplied from the transformer, and when a ground fault is detected through the ground fault relay, a buzzer is generated for a predetermined time while generating an alarm. A high resistance grounding device, comprising: a generator. The method of claim 1, The apparatus includes a voltage transducer for measuring the voltage across the high resistance portion; A voltage meter installed on the front of the housing and displaying a voltage across the high resistance part measured by the voltage transducer to an operator; A current transducer mounted between the high resistance section and the ground, the current transducer measuring a rated current flowing in the high resistance section when a ground fault occurs; And And a current meter installed on the front of the housing, the current meter further displaying the rated current value measured by the current transducer to the operator. The method of claim 1, The apparatus may include: a temperature sensor unit configured to detect a temperature when the temperature inside the housing rises above a predetermined temperature due to overheating of the high resistance unit and output a temperature rise detection signal; A fan installed at a rear side of the housing and driving when the temperature rise detection signal is input from the temperature sensor unit; A limit switch installed at the door of the housing and detecting whether the door is opened or closed; A lamp installed on the front of the housing and turned on or off according to on / off of the limit switch; And It is installed on the front of the housing, and connected between the fan and the lamp and the transformer, the fan / lamp push button to further connect or short-circuit the fan and the lamp and the transformer according to the operator's pressing operation further High resistance grounding device, characterized in that included. The method of claim 1, The device is mounted on the front side of the housing and is connected between a connection point (c) between the high resistance portion and the earth and a power pushbutton connected to the neutral point (N) of the transformer or generator, to the operator's choice. And a test switch for driving the meta relay by switching the rated voltage applied to the neutral point (N) of the transformer or the generator to flow to the high resistance part when the power supply is turned on. According to claim 1, The range of the minimum current value canceled by the high resistance section is " 0.1 to 0.8 A ". The method of claim 1, The alarm and pulse generating means, the green lamp is installed on the front portion of the housing, indicating a normal state; A red lamp installed in the front portion of the housing to indicate a dangerous state in case of a ground fault; Connected between the transformer and the green / red lamp to short the b contact between the transformer and the green lamp in the normal state to turn on the green lamp, and when the meta relay is driven as a ground fault occurs. an MR switch which disconnects b contact and shorts a contact between the transformer and the red lamp to turn off the green lamp and to turn on the red lamp; A green lamp test button installed in a front portion of the housing and connected between the MR switch and the green lamp to test a lighting state of the green lamp according to an operator's pressing operation; A red lamp test button installed in a front portion of the housing and connected between the MR switch and the red lamp to test a lighting state of the red lamp according to an operator's pressing operation; A first alarm connected to a contact of the MR switch to generate an alarm for a predetermined time when the red lamp is turned on; A select switch installed at a front surface of the housing and connected to the a contact of the MR switch to select a pulse generation mode according to an operator's selection; And When the pulse generation mode is selected through the select switch, a high resistance grounding device comprising a pulse generator for generating a pulse for detecting a bad point to the transformer or generator of the system at regular intervals. The method of claim 1, The buzzer generating means may include: a ground fault relay driven as a ground fault is detected through the ground fault relay; A second alarm connected to the ground relay and generating an alarm when the ground relay is driven; A buzzer selection switch installed at a front portion of the housing and connected to the ground relay to turn on a buzzer function according to a selection of an operator in a normal state; A buzzer generator for generating a buzzer for a predetermined time when the ground relay is driven and the buzzer selection switch is turned on; And It is installed on the front of the housing, the high resistance grounding device, characterized in that it is connected between the ground relay and the buzzer generating unit, consisting of a buzzer stop button for stopping the buzzer generating unit according to the operator's pressing operation.

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