KR102415477B1 - Electrical failure detection and management device - Google Patents

Abstract

An electrical failure detection and management device comprises: a switchboard provided on a power source side; at least one distribution board connected to a lower end of the switchboard through a power line and a neutral line; and a test measurement unit testing an electrical system in a load-side direction below the switchboard. The distribution board includes: first switches provided at a plurality of branches connected to the distribution board, respectively, to open and close a power line and a neutral line; overcurrent blocking units connected to the lower ends of the first switches to block overcurrent; and switching units connected to the lower ends of the overcurrent blocking units, respectively, and switching to anyone between a first switching state and a second switching state, wherein, in the first switching state, the overcurrent blocking unit is electrically connected to a load side, and in the second switching state, the power line and the neutral line of the overcurrent blocking unit are connected by adding an additional impedance. The test measurement unit includes: a source generating unit adding a test power signal to the power line; a signal measurement unit measuring a power signal supplied to the power line and a reflected power signal; and a test control unit controlling the opening and closing of a plurality of the first switches, controlling the source generating unit to generate a test power signal in a state in which the switching unit is switched to one between the first switching state and the second switching state, and then receiving the measured value from the signal measuring unit to test the state of the power line at the bottom of the switchboard and the state of the power line in each of the plurality of branches. The present invention can enhance efficiency and accuracy in detecting electrical failures.

Description

Electrical failure detection and management device

The present invention relates to an electrical failure detection and management device.

In general, electrical equipment refers to machinery, equipment, dams, waterways, reservoirs, electric lines, security communication lines, and other facilities installed for power generation, transmission, substation, distribution, or use of electricity. , private electric equipments fall under this category, and as an example of the electric equipment, a three-phase four-wire distribution system uses a method such as Y connection, delta connection, and Y delta connection to connect neutral (N) and power lines (R phase, S phase, T). phase) to supply power. Here, when connecting to a load, it becomes 380V when one power line and another power line are connected, and becomes 220V when one power line (eg, phase A) and the neutral line (N) are connected, and power is supplied to a single-phase load.

Electric fires do not decrease every year, and most of the fires occur in low-voltage customers because of the poor electrical facilities of low-voltage customers rather than high-voltage customers. In the event of an electrical failure such as supply voltage, misconnected electricity, surge, abnormal voltage, resistance increase, or poor connection (arc) in electrical equipment in the customer, the low-voltage customer takes no measures against the electrical failure. Because it is not possible to set up the system, an abnormal voltage is introduced into the load, or electrical equipment is overheated and burned, resulting in electric shock and electric fire.

From the entrance that receives electricity in the low-voltage consumer building to the distribution boards equipped with circuit breakers, it is a blind spot for monitoring electrical failures such as short circuits. , There are various causes of such electric fires, and the main factors among them are as follows.

First, with a short circuit, the shell (coating) of the wire is peeled off, fixed to the wire with nails, pins, etc., or a heavy object is placed on a movable wire so that the two strands of the wire are in contact with direct or indirect resistance so that the current can flow easily. A short circuit (short circuit) occurs because it flows intensively to the contacting parts where possible, and at this time, a spark is generated by contact between the conductors, which leads to a fire.

An overload occurs when an amount of electricity greater than the rated capacity is used in excess or an unbalanced current, and excessive heat is generated in the connection part of the electric wire, the electric device itself, or the wiring mechanism, and a fire is generated.

Unbalanced voltage is caused by phase loss, disconnection, failure of load equipment in balanced loads (three-phase motors, etc.) The overcurrent of a three-phase balanced load can be protected to some extent with an electronic overload relay (EOCR). The protection is not easy beyond the supply of control power. In particular, if the neutral wire is disconnected from the single-phase, two-wire system on the power side, a power outage occurs on the load side and the relay (breaker) becomes inoperable. Even in the event of burnout, overheating, or fire, it is impossible to take any measures to cut off the faulty electricity.

A short circuit is when electricity flows to the outside through an object other than a wire through which electricity flows. In a short circuit fire, the current flows to buildings and ancillary facilities without passing through the designed passageway, and heat accumulates, which generates heat and causes a fire.

Poor connection and half-break means that the connection point of the wire (branching of the circuit, etc.) or the conductor inside the wire is disconnected and the connection or break is repeated, causing an arc, resistance, and disturbance in the flow of current. When accumulated, the wire's coating is carbonized and the + and - electrodes, which are the conductors of the wire, collide, causing a fire.

As such, the causes of electric fires are various, and as an example of a device for detecting an electric failure that can cause such an electric fire, Korean Patent Laid-Open No. 10-2019-0128920 can be cited.

However, only a device for detecting such an electrical failure is insufficient as a countermeasure against an electrical fire.

The present invention provides an apparatus for improving the efficiency and accuracy of fault detection of electrical facilities in an apartment house.

a switchboard provided on the power supply side; at least one switchboard connected to a lower end of the switchboard by a power line and a neutral line; and a test measurement unit for testing the electrical system in the direction of the load side under the switchboard;

The distribution board may include: a first switch provided in each of a plurality of branches connected to the distribution board to open and close a power line and a neutral wire; an overcurrent blocking unit connected to a lower end of the first switch to block an overcurrent; A first switching state that is connected to the lower end of each of the overcurrent breaker and electrically connects the overcurrent breaker and the load side, and a second switching state that connects between the power line and the neutral line of the overcurrent breaker by adding an additional impedance a switching unit for switching; including,

The test measurement unit may include: a source generator for adding a test power signal to the power line; a signal measuring unit measuring a power signal supplied to the power line and a reflected power signal; and controlling opening/closing of the plurality of first switches, and controlling the source generator to generate a test power signal in a state in which the switching unit is switched to any one of a first switching state and a second switching state, and then from the signal measuring unit. and a test control unit that receives the measurement value and tests the state of the power line at the bottom of the switchboard and the state of each of the plurality of branches.

In addition, it includes; a current sensing unit for sensing the current of the ground wire on the switchboard side of the neutral wire; The test measurement unit includes a current measuring unit for calculating the presence or absence of the current flowing through the neutral wire from the current sensing unit and the amount of current; have.

In addition, the test control unit may determine that there is a short circuit from the power line at the bottom of the switchboard when the current flows from the current sensing unit for a certain amount or more after all of the first switches are turned to the off state.

In addition, the test control unit sequentially converts the first switches to the on-state, and at the same time switches the switching unit corresponding to the first switch switched to the on-state to the second switching state, and then the test measured by the signal measuring unit From the power signal data, it may be determined whether the power line to the ground including the first switch switched to the on state is normal.

In addition, when a specific first switch is switched to an on state, and a current flows from the current sensing unit more than a certain amount in a state in which a switching unit corresponding to the specific first switch is switched to a second switching state, including the specific first switch It can be determined that there is a short circuit in the ground.

In addition, the additional impedance provided in the switching units may be provided such that at least one of a magnitude and a phase difference increases in magnitude by a predetermined amount.

In addition, the test control unit switches all of the first switches to an on state, and after switching all of the switching units to a second switching state, the test power signal data measured by the signal measuring unit indicates the normality of the power lines of each of the branches. It can be determined whether

In addition, an electrical failure detection and recovery unit connected to the power and load sides of the power line and the neutral line to detect an electrical failure and to perform at least any one or more of recovery, blocking, alarm, notification, monitoring and control for the location of the electrical failure; can be provided.

The management device according to the present invention can improve the efficiency and accuracy of detecting an electrical failure of an apartment house or the like.

1 shows an example of a power distribution system.
2 shows an example of a power distribution system including an electric failure detection and recovery unit.
3 is a block diagram schematically illustrating an electrical failure detection and management apparatus according to an embodiment.
4 and 5 are block diagrams illustrating a circuit state according to switching of a switching unit.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. Unless there is a specific definition or reference, the terms indicating the direction used in this description are based on the state indicated in the drawings. In addition, the same reference numerals refer to the same members throughout each embodiment. On the other hand, each component shown in the drawings may have an exaggerated thickness or dimension for convenience of description, and does not mean that it should actually be configured in a ratio between the corresponding dimensions or components.

It will be described with reference to FIGS. 1 and 2 . 1 shows an example of a general power distribution system, and FIG. 2 shows an example of a power distribution system including a conventional electric failure detection and recovery unit.

Existing single-phase or multi-phase multi-wire type (eg, single-phase 2-wire type, single-phase 3-wire type, three-phase 3-wire type, three-phase 4-wire type, etc.) electricity provided in the distribution system (eg, 100 in FIGS. 1 and 2) A power-side detection/recovery device 240 connected in parallel to a power line of a facility (eg, 300, 400, 500, 600, 700, 800 in FIGS. 1 and 2 ). It has its own neutral point (the first neutral point) and is connected to the neutral line (N) of the electrical equipment or connected to the second neutral point (N2) of the load side detection/recovery device 230 to power lines (power supply lines, bus ducts, etc.) ) to block, detect, or restore when an electrical failure occurs.

The load-side detection/recovery device 230 connected in parallel to the power lines of the load-side electrical equipment (eg, 290 and 900 in FIG. 2 ), which itself has another neutral point (second neutral point). Connect this second neutral point (N2) to the neutral wire (N) of the electrical equipment on the power supply side, or connect it to the first neutral point (N1) of the detection/recovery device 240 on the power supply side. 270) to immediately cut off the power, or detect/detect an electrical failure to block, alarm, notify, restore, and control.

In this case, electrical failure means electrical equipment (transformer, generator, UPS, switchboard, distribution board, control panel, switchgear, circuit breaker, wire line, switch, fuse, terminal, outlet, bus duct, etc.) configured in the distribution system or the power line of this distribution system, etc. It refers to increased resistance, arc, disconnection, phase loss, unbalanced power (abnormal voltage, abnormal current), poor connection, incorrect wiring, leakage, short circuit, etc.

A fault detector 210 for detecting the occurrence of an electrical failure on the power side in conjunction with the load side detection/recovery device 230 . The fault detector 210 detects the current of the main power lines (R, S, T or R, N, etc.) connected in parallel to the load-side detection/recovery device 230, or the load-side detection/recovery device 230 2 Detects the current value of the neutral wire (N) connected to the neutral point (N2) or the first neutral point (N1) connected to the second neutral point (N2), or the first neutral point (N1), the second neutral point (N2), the neutral wire The following controller 220 detects the voltage in any two of (N) and the earth (E) and immediately cuts off, restores, alarms, notifies of a failure, or sets the detected failure detection value including its location information. forward to

The alarm generator 250 alerts the failure occurrence and failure section, place, and failure location detected by the failure detector 210 or determined by the controller 220 as a visual and/or audible alarm. The alarm cancellation input unit 260 receives a signal for canceling the generated alarm (eg, when the alarm cancellation switch is operated) and generates an alarm cancellation signal.

The circuit breaker 270 cuts off the power line and the load side power line and the neutral line of the distribution system according to the detection of the occurrence of a failure by the failure detector 210 or according to the cutoff signal of the controller 220 below.

The controller 220 receives the fault detection value including the fault section, fault location, and fault location from the output of the fault detector 210, determines the electrical fault of the electrical equipment, and immediately restores the fault section, fault location, and fault location. , outputs an alarm or blocking signal that operates the alarm generator 250 or circuit breaker 270, and notifies an external manager of the failure situation by wire or wireless using a communication module, or detects (monitors) a failure situation through two-way communication and controlled by the manager.

The power-side detection/recovery device 240 is, for example, a main voltage transformer (eg, 300 in FIGS. 1 and 2) of a distribution system (eg, 100 in FIG. 1), which is an electrical installation, and a switchboard (eg, in FIG. 1). 2 400), a control panel (eg, 500 in FIG. 2), UPS (eg, 600 in FIG. 2), a generator (eg, 700 in FIG. 2), a distribution board (eg, 800 in FIG. 2), etc. Electrical equipment to receive power is connected in parallel to the power line (bus duct, etc.) of When detecting, blocking, and notifying the power-side detection/recovery unit 240, the minimum capacity for fault detection is configured.

An electric failure detection and management apparatus according to an embodiment of the present invention will be described with reference to FIGS. 3 to 5 . 3 is a block diagram schematically illustrating an electrical failure detection and management apparatus according to an embodiment, and FIGS. 4 and 5 are block diagrams illustrating a circuit state according to switching of a switching unit.

The electrical failure detection and management apparatus according to the present embodiment is configured to improve accuracy while efficiently determining the state of the power line and whether there is a short circuit in addition to the general electrical failure detection/recovery apparatus described above.

The current sensing unit 1100 is provided on the ground line En extending from the neutral line N on the switchboard 400 side to sense a current flowing through the ground line En. If the insulation on the load side is bad, the current as much as the calculated insulation resistance value and the ground resistance value flows to the ground wire (En). The current sensing unit 1100 may be implemented as, for example, a device including a coil surrounding the periphery of the neutral wire (N). When a current flowing through the neutral wire (N) is generated and the current fluctuates, a magnetic field is generated, and the change and amount of the current can be detected by detecting the magnetic field. When a signal according to a change in the amount of current is generated through the current sensing unit 1100, this signal is transmitted to a current measuring unit 1130 to be described later and used to calculate the presence or absence of current flowing through the neutral wire (N) and the amount of current do.

The distribution board 800 includes a first switch 810 , an overcurrent blocking unit 820 , and a switching unit 830 . The distribution board 800 may form a plurality of branches B1 and B2, and includes a first switch 810, an overcurrent blocking unit 820, and a switching unit 830 for each branch.

The first switch 810 is provided in each of the plurality of branches connected to the distribution board 800 to open and close the power line and the neutral line. The overcurrent blocking unit 820 is respectively connected to the lower end of the first switch 810 to block the current passing through the corresponding branch when the current is equal to or greater than a predetermined reference value, that is, when the overcurrent flows.

The switching unit 830 is connected to the lower end of each of the overcurrent blocking units 820 . The switching unit 830 electrically connects the first switching state, that is, the overcurrent blocking unit 820 and the load 290 side, as shown in FIG. 4 in normal times. The switching unit 830 also switches to any one of the second switching states in which an additional impedance is added and connected between the power line and the neutral line of the overcurrent blocking unit as shown in FIG. 5 . In this case, the additional impedance may be provided in the switching units 830 for each branch so that at least one of a magnitude and a phase difference increases in magnitude by a predetermined amount. Through this, by connecting the impedance of each branch in a preset state in the second switching state, it is possible to design the reflection characteristic of each branch in advance. By analyzing the signal measured by the signal measuring unit 1110 using these characteristics and comparing the predicted signal with the actual measured signal, the state of each branch can be determined, and the state of the actual load connected, that is, the first switching In this state, it is possible to determine the power supply and reflection characteristics in an actual use state by comparing the signal measured by the signal measuring unit 1110 .

The outlet 900 functions as a connection point for connecting the loads 290 to each branch, and the load 290 is connected to each branch through the outlet 900 to receive power.

The test measurement unit 1000 is a component that tests the electrical system in the load side direction below the switchboard. The test measurement unit 1000 includes a signal measurement unit 1110 , a source generator 1120 , a current measurement unit 1130 , and a test control unit 1140 .

The source generator 1120 generates a square wave having a constant amplitude and period, and adds it to the power line R. The signal measuring unit 1110 measures the test signal generated from the source generating unit 1120 and the reflected signal reflected through the power line (R) and the neutral line (N). The signal generated from the source generator 1120 is reflected back through the power line R and each branch due to the mismatch of the load. to measure the signal.

The current measuring unit 1130 calculates the presence or absence of current flowing through the neutral wire and the amount of current through the current sensing unit 1100 described above.

The test control unit 1140 receives whether the current is sensed and the sensing amount from the current measuring unit 1130 . In addition, the test control unit 1140 controls the first switch 810 and the switching unit 830 to simultaneously generate a test signal from the source generator 1120 , and measures the reflected signal accordingly to test the power system. will do When the test signal is a realization wave, the reflected signal may be measured in a form of attenuating the magnitude of the test signal. For this reason, the measured signal may be measured in a form in which the test signal is measured and the test signal is attenuated after a predetermined time elapses. In addition, depending on the phase delay of the power system at the time of signal measurement, the attenuated form may appear in an exponentially increasing or decreasing form rather than a straight line. For this reason, when the magnitude and phase delay amount of the additional impedance provided in the switching unit are known, the attenuation pattern on the graph of the reflected signal can be predicted, and inversely, depending on the shape of the graph of the measured test signal and the reflected signal, or the reflected signal It becomes possible to more accurately detect a fault in an electrical problem by adding more information about the time of occurrence of .

The test controller 1140 may perform the following test method. Meanwhile, the test control unit 1140 may control to cut off the power supply from the switchboard in order to perform such a test. The test control unit 1140 controls opening and closing of the plurality of first switches 810 and generates a source in a state in which each of the switching units 830 is switched to any one of the first switching state and the second switching state as described above. After controlling the unit 1120 to generate a test power signal, the measured value is received from the signal measuring unit 1110 to test the state of the power line at the bottom of the switchboard 400 and/or the state of each power line with a plurality of branches.

Each of the switching units 830 has an impedance different in size by a certain amount, and in the first switching state, as shown in FIG. 4 , the overcurrent blocking unit 820 and the outlet 900 are connected to supply normal power. In the second switching state, as shown in FIG. 5 , the overcurrent blocking unit 820 and the outlet 900 are cut off and the R line and the neutral line are connected with the corresponding impedance.

For example, the test control unit 1140, after switching all of the first switch 810 to the off state, when the current flows from the current sensing unit 1100 for a certain amount or more, from the power line (except the ground) at the bottom of the switchboard 400 It can be determined that there is a leak.

In addition, the test control unit 1140 sequentially switches the first switches 810 into the on-state one by one, and at the same time switches the switching unit 830 corresponding to the first switch 810 switched to the on-state to the second switching state. do. At this time, it may be determined whether the power line to the ground including the corresponding first switch (on state) is normal from the test power signal and the reflected signal data measured by the signal measuring unit.

In addition, in a state in which the specific first switch 810 is switched to the on state, and the switching unit 830 corresponding to the specific first switch 810 is switched to the second switching state, the neutral wire from the current sensing unit 1100 When it is sensed that current flows over a certain level, it may be determined that there is a short circuit in the ground including the above-described specific first switch 810 .

In addition, the test control unit 810 converts all of the first switches 810 to the on state, and converts all of the switching units to the second switching state, and then from the test power signal and reflected signal data measured by the signal measuring unit 1110 . It can be determined whether the power lines of each of the branches are normal. At this time, as described above, each branch can be distinguished by providing the additional impedance included in the switching unit 830 of each branch so that at least one of a magnitude and a phase difference increases in magnitude by a predetermined amount. That is, by connecting the additional impedance of each branch in a preset state in the second switching state, the reflection characteristic for each branch can be designed in advance. By analyzing the signal measured by the signal measuring unit 1110 using these characteristics and comparing the predicted signal with the actual measured signal, the state of each branch can be determined, and the state of the actual load connected, that is, the first switching In this state, it is possible to determine the power supply and reflection characteristics in the actual use state by comparing the signal measured by the signal measuring unit 1110 .

As described above, it is provided together or alone with the general electric failure detection and recovery unit (device) described above to more accurately and efficiently detect an electric failure.

Although the preferred embodiment of the present invention has been described above, the technical spirit of the present invention is not limited to the above-described preferred embodiment, and can be implemented in various ways without departing from the technical spirit of the present invention embodied in the claims. have.

810: first switch
820: over-current blocking unit
830: switching unit
1000: test measurement unit
1100: current sensing unit
1110: signal measuring unit
1120: source generating unit
1130: current measuring unit
1140: test control
100 - distribution system (or electrical equipment)
120 - 1st leg, 130 - 2nd leg, 140 - 3rd leg
150 - Detection/recovery distribution system (construction method of electric failure universal detection and recovery distribution system according to a preferred embodiment of the present invention)
200 - Electric failure universal detection and recovery distribution system according to a preferred embodiment of the present invention
210 - Failure detector (SSR, ZCT, CT, voltage, current detector, relay, earth leakage breaker, etc.)
220 - controller, 230 - load-side detection/recovery device, 240 - power-side detection/recovery device
250 - alarm generator, 260 - alarm release input device,
290 - Load (electrical equipment, home appliance, light (lighting), disaster prevention equipment, communication equipment, etc.)
300 - main transformer (or power-side detection/recovery device 240 with primary coil)
400 - switchboard,
500 - motor control panel (or control panel);
600 - UPS (Uninterruptible Power Supply)
700 - Emergency power (generator, ESS, charger, etc.)
800 - distribution board
900 - outlet

Claims (8)

a switchboard provided on the power supply side;
at least one switchboard connected to a lower end of the switchboard by a power line and a neutral line; and
Including; a test measurement unit for testing the electrical system in the direction of the load side under the switchboard;
The distribution panel is
a first switch provided in each of the plurality of branches connected to the distribution board to open and close a power line and a neutral line;
an overcurrent blocking unit connected to a lower end of the first switch to block an overcurrent; and
A first switching state that is connected to the lower end of each of the overcurrent breaker and electrically connects the overcurrent breaker and the load side, and a second switching state that connects between the power line and the neutral line of the overcurrent breaker by adding an additional impedance a switching unit for switching; including,
The test measurement unit,
a source generator for adding a test power signal to the power line;
a signal measuring unit measuring a power signal supplied to the power line and a reflected power signal; and
Control the opening and closing of the plurality of first switches, control the source generator to generate a test power signal in a state in which the switching unit is switched to any one of a first switching state and a second switching state, and then measure from the signal measuring unit A test control unit for receiving a value and testing the state of the power line at the lower end of the switchboard and the state of each power line with the plurality of branches;
Including; a current sensing unit for sensing the current of the ground wire on the switchboard side of the neutral wire;
The test measurement unit includes a current measurement unit for calculating the presence or absence of a current flowing through the neutral wire from the current sensing unit and the amount of current. delete According to claim 1,
The test control unit,
Electrical failure detection and management device for determining that there is a short circuit from the power line at the bottom of the switchboard when the current flows from the current sensing unit after turning all of the first switches to the off state. According to claim 1,
The test control unit,
After sequentially switching the first switches to the on-state and simultaneously switching the switching unit corresponding to the first switch switched to the on-state to the second switching state, the on-state from the test power signal data measured by the signal measuring unit An electrical failure detection and management device for determining whether the power line of the ground including the first switch switched to the state is normal. 5. The method of claim 4,
A branch including the specific first switch when a specific first switch is switched to an on state, and a current flows from the current sensing unit to a predetermined or more in a state in which a switching unit corresponding to the specific first switch is switched to a second switching state An electrical fault detection and management device that determines that there is a short circuit in the The method of claim 1,
The additional impedance provided in the switching units is an electrical failure detection and management device provided so that at least one of a magnitude and a phase difference increases in magnitude by a predetermined amount. 7. The method of claim 6,
The test control unit turns all the first switches into an on state, and after switching all the switching units to a second switching state, whether the power lines of each of the branches are normal from the test power signal data measured by the signal measuring unit Electrical failure detection and management device to determine. The method of claim 1,
An electrical failure detection and recovery unit connected to the power and load sides of the power line and the neutral line to detect an electrical failure and to perform at least any one or more of recovery, blocking, alarm, notification, monitoring and control of the location of the electrical failure. Electrical failure detection and management device provided.

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