WO2018116860A1

WO2018116860A1 - Electrical path anomaly detection device and switch equipped therewith

Info

Publication number: WO2018116860A1
Application number: PCT/JP2017/044106
Authority: WO
Inventors: 翔毛; 宏一山添; 澤田　知行; 省互一村; 航原田
Original assignee: パナソニックＩｐマネジメント株式会社
Priority date: 2016-12-20
Filing date: 2017-12-08
Publication date: 2018-06-28
Also published as: CN110088871A; JP6839813B2; JP2018101549A; CN110088871B

Abstract

The objective of the present invention is to reduce the generation of heat from a power source circuit section. The power source circuit section (20) comprises a power storage unit (30), switch units (40), a voltage detection unit (50), and a control unit (50). The power storage unit (30) is charged by a direct current voltage inputted into an input terminal unit (21) from an electrical path where detection is carried out by an anomaly detection section (60). The voltage charged into the power storage unit (30) is outputted as a power source voltage (V1) to the anomaly detection section (60). The switch units (40) switch the state of the power storage unit (30) between either a charging state and a charging stopped state. The voltage detection unit (50) detects the power source voltage (V1). The control unit (50) controls the switch units (40) according to the detection result from the voltage detection unit (50).

Description

Electric circuit abnormality detection device and switch provided with the same

The present disclosure relates to an electric circuit abnormality detection device and a switch including the same. More specifically, the present disclosure relates to an electric circuit abnormality detection device that detects the presence or absence of an abnormality in an electric circuit to be detected, and a switch including the same.

Conventionally, there has been proposed an earth leakage breaker that forcibly opens a main contact when a leakage current flowing through a main circuit is detected or a phase failure of a neutral wire is detected (see, for example, Patent Document 1). In the earth leakage breaker disclosed in Patent Document 1, the earth leakage protection IC for detecting the earth leakage current, the phase failure protection IC for detecting the phase failure of the neutral wire, the earth leakage protection IC, and the phase failure protection IC And a power supply circuit section for supplying an operating voltage. In the power supply circuit unit, the AC voltage is rectified by a diode bridge, and the pulsating voltage output from the diode bridge is stepped down by a series circuit of a plurality of resistors. Further, the power supply circuit unit obtains the operating voltages of the leakage protection IC and the phase loss protection IC by making the voltage stepped down by a series circuit of a plurality of resistors constant by a Zener diode and smoothing it by a smoothing capacitor. .

In the power circuit section of the earth leakage breaker disclosed in Patent Document 1, the pulsating voltage output from the diode bridge is stepped down by a series circuit of a plurality of resistors, so that the internal temperature of the earth leakage breaker can rise due to the heat generated by the resistors. There is sex.

JP 2003-7191 A

An object of the present disclosure is to provide an electric circuit abnormality detection device capable of reducing heat generation in a power supply circuit unit, and a switch including the same.

The electric circuit abnormality detection device according to one aspect of the present disclosure includes an abnormality detection unit that detects whether there is an abnormality in an electric circuit to be detected, and a power supply circuit unit that outputs a power supply voltage to the abnormality detection unit. The power supply circuit unit includes an input terminal unit, a power storage unit, an output terminal unit, a switch unit, a voltage detection unit, and a control unit. The electric circuit to be detected is electrically connected to the input terminal portion. The power storage unit is charged by a DC voltage input to the input terminal unit. The abnormality detection unit is electrically connected to the output terminal unit. The output terminal unit is a terminal unit for outputting a voltage charged in the power storage unit to the abnormality detection unit as the power supply voltage. The switch unit is configured to change a state of the power storage unit between a charge state in which a charge current flows from the electric circuit to be detected to the power storage unit via the input terminal unit and a charge stop state in which a charge current does not flow to the power storage unit. Switch to one. The voltage detection unit detects the power supply voltage output from the power storage unit to the abnormality detection unit. The control unit controls the switch unit according to a detection result of the voltage detection unit.

The switch according to an aspect of the present disclosure includes the electric circuit abnormality detection device and a power switch that is electrically connected to the electric circuit to be detected. The power switch is controlled by the electric circuit abnormality detection device based on a detection result of the abnormality detection unit.

FIG. 1 is a circuit diagram of a switch including an electrical path abnormality detection device according to an embodiment of the present disclosure. FIG. 2 is a circuit diagram of a switch according to Modification 1 of the embodiment of the present disclosure. FIG. 3 is a circuit diagram of a switch according to Modification 2 of the embodiment of the present disclosure.

The embodiment described below is only one of various embodiments of the present disclosure. Embodiments of the present disclosure are not limited to the following embodiments, and may include other embodiments. In addition, the following embodiments can be variously changed according to the design or the like as long as they do not depart from the technical idea according to the present disclosure.

(1) Configuration of Electric Circuit Abnormality Detection Device and Switch As shown in FIG. 1, the electric circuit abnormality detection device 10 according to the present embodiment is provided in a switch 1 with a leakage breaker function. The switch 1 is housed in a distribution board installed in a building such as a house, and is used as a main switch. The switch 1 is electrically connected to the four electric paths 2 in, for example, a three-phase four-wire distribution system that supplies three-phase AC power using the four electric paths 2. The switch 1 has an earth leakage cutoff function and functions to cut off the power supply to the load when a ground fault occurs.

The switch 1 is electrically connected to four electric circuits 2 from an AC power source 3. A conductive member 4 that is electrically connected to each of the four electric paths 2 is housed inside the switch 1. Here, the four electric circuits 2 include an R-phase electric circuit 2R, an S-phase electric circuit 2S, a T-phase electric circuit 2T, and an N-phase electric circuit 2N. The four conductive members 4 include an R-phase conductive member 4R, an S-phase conductive member 4S, a T-phase conductive member 4T, and an N-phase conductive member 4N. In the following description, when a specific electric circuit is described, it is described as an

electric circuit

2R, 2S, 2T, 2N, and when the

electric circuit

2R, 2S, 2T, 2N is described without being distinguished, it is described as an electric circuit 2. Similarly, when describing a specific conductive member, it describes as the

conductive member

4R, 4S, 4T, 4N, and when describing without distinguishing the

conductive member

4R, 4S, 4T, 4N, it describes as the conductive member 4.

Switch 1 is an earth leakage circuit breaker having an earth leakage detection function. The switch 1 includes an electrical path abnormality detection device 10 and four contacts 5b (power switches) that are electrically connected to the four conductive members 4, respectively. The electric circuit abnormality detection device 10 detects the presence or absence of abnormality in the electric circuit 2 to be detected, and the contact 5b is controlled based on the abnormality detection result by the electric circuit abnormality detection device 10.

Hereinafter, the configuration of each part of the electric circuit abnormality detection device 10 and the switch 1 will be described.

The electric circuit abnormality detection device 10 includes a power supply circuit unit 20 and an abnormality detection unit 60.

The abnormality detection unit 60 uses the four electric circuits 2 electrically connected to the AC power supply 3 as detection targets, and detects the presence / absence of an abnormality in the four electric circuits 2 that are detection targets. The abnormality detection unit 60 of the present embodiment detects that there is an abnormality in the electric circuit 2 when detecting a leakage current in any of the four electric circuits 2.

The power supply circuit unit 20 obtains electric power from the electric circuit 2 to be detected and outputs the power supply voltage V1 to the abnormality detection unit 60.

The power supply circuit unit 20 includes an input terminal unit 21, an output terminal unit 22, a power storage unit 30, a switch unit 40, and a voltage detection unit 50.

The conductive member 4 that is electrically connected to the electric circuit 2 to be detected is electrically connected to the input terminal portion 21. The input terminal unit 21 includes a pair of

input terminals

21a and 21b. The input terminal 21a is electrically connected to the DC output terminal on the positive side of the full-wave rectifiers 11 and 12 via the solenoid coil 5a. The input terminal 21 b is electrically connected to the DC output terminal on the negative side of the full-wave rectifiers 11 and 12. Of the pair of AC input terminals of the full-wave rectifier 11, the T-phase conductive member 4T is electrically connected to one AC input terminal, and the S-phase conductive member 4S is electrically connected to the other AC input terminal. Connected. Of the pair of AC input terminals of the full-wave rectifier 12, the R-phase conductive member 4R is electrically connected to one AC input terminal, and the N-phase conductive member 4N is electrically connected to the other AC input terminal. It is connected. That is, the power supply circuit unit 20 generates a power supply voltage for the abnormality detection unit 60 or the like from either an AC voltage of about 220 V between the R phase and the T phase and an AC voltage of about 220 V between the S phase and the N phase. Here, the

input terminals

21a and 21b may be components (terminals) for connecting electric wires or the like, but may be, for example, leads of electronic components or part of a conductor formed as wiring on a circuit board. Further, there is a surge between the R-phase conductive member 4R, the S-phase conductive member 4S, the T-phase conductive member 4T, and the N-phase conductive member 4N connected to the AC input terminals of the full-wave rectifiers 11 and 12. A protective element or the like may be connected.

The power storage unit 30 is, for example, a capacitor and is charged by a DC voltage input from the electric circuit 2 via the

input terminals

21a and 21b.

The abnormality detection unit 60 is electrically connected to the output terminal unit 22. The output terminal unit 22 includes a pair of

output terminals

22a and 22b. The abnormality detection unit 60 is electrically connected between the output terminal 22a and the output terminal 22b. The power storage unit 30 is electrically connected between the output terminal 22a and the output terminal 22b, and a voltage (charge voltage) charged in the power storage unit 30 is output to the abnormality detection unit 60 as the power supply voltage V1. The A Zener diode 33 for overvoltage protection is electrically connected between the output terminal 22a and the output terminal 22b.

The switch unit 40 switches the state of the power storage unit 30 between a charging state in which a charging current flows from the electric circuit 2 to be detected to the power storage unit 30 and a charging stop state in which the charging current does not flow through the power storage unit 30. In this embodiment, the switch part 40 is controlled by the voltage detection part 50 to either a charge state or a charge stop state. In other words, the voltage detection unit 50 that is a control unit controls the switch unit 40 to either the charging state or the charging stop state based on the power supply voltage V <b> 1 of the power storage unit 30. That is, the voltage detection unit 50 also functions as a control unit that controls the switch unit 40 according to the detection result of the voltage detection unit 50, but the voltage detection unit 50 and the control unit are configured by separate circuits. May be.

The switch unit 40 of this embodiment includes a first switching element 41 and a second switching element 42. The first switching element 41 and the power storage unit 30 are electrically connected in series between the input terminal 21a and the input terminal 21b. In addition, a resistor 31 as a first impedance element and a second switching element 42 are electrically connected in series between the input terminal 21a and the input terminal 21b. Specifically, each of the first switching element 41 and the second switching element 42 is an N-channel enhancement type MOSFET (Metal-Oxide-Semiconductor-Field-Effect-Transistor). The drain electrode of the first switching element 41 is electrically connected to the input terminal 21a. The power storage unit 30 is electrically connected between the source electrode of the first switching element 41 and the input terminal 21b. A resistor 31 is electrically connected between the input terminal 21 a and the drain electrode of the second switching element 42. The source electrode of the second switching element 42 is electrically connected to the input terminal 21b. The gate electrode of the first switching element 41 is electrically connected to the connection point between the resistor 31 and the second switching element 42. The gate electrode of the second switching element 42 is electrically connected to the output terminal of the voltage detection unit 50. A capacitor 32 for preventing noise is electrically connected between the input terminal 21a and the input terminal 21b.

The voltage detection unit 50 detects the voltage (that is, the power supply voltage of the abnormality detection unit 60) V1 charged in the power storage unit 30. The switch unit 40 of this embodiment is controlled according to the detection result of the voltage detection unit 50. That is, the switch unit 40 changes the state of the power storage unit 30 between the charge state and the charge stop according to the level of the power supply voltage V1 detected by the voltage detection unit 50 and a predetermined reference voltage (charge start voltage and charge stop voltage). It is controlled to switch to any of the states. The charge stop voltage is set to a voltage higher than the charge start voltage. Both the voltage value of the charge stop voltage and the charge start voltage are voltage values at which the abnormality detection unit 60 can operate. In this embodiment, the charge stop voltage is set to about 5.3 V, and the charge start voltage is about 4.6 V. Is set to

When the power supply voltage V1 exceeds the charge stop voltage, the voltage detection unit 50 applies a voltage higher than the threshold voltage to the gate electrode of the second switching element 42, turns on the second switching element 42, and turns on the first switching element 41. The power storage unit 30 is set in a charge stop state by turning off. When the power supply voltage V1 becomes equal to or lower than the charging start voltage, the voltage detection unit 50 turns off the second switching element 42 and turns on the first switching element 41 to put the power storage unit 30 in a charged state.

Here, in the comparison between two values such as voltage, the term “exceeds” includes the case where one of the two values exceeds the other. However, the present invention is not limited to this, and “exceeding” here may be “more than”. That is, whether or not to include the case where the two values are equal can be arbitrarily changed depending on the setting of the reference voltage or the like, so there is no technical difference between “exceeding” and “exceeding”. Similarly, “less than” may be “less than”.

The voltage detection unit 50 also includes a power supply voltage V1 (charge start voltage) when the second switching element 42 is turned on from off and a power supply voltage V1 (charge stop when the second switching element 42 is turned off from on. Hysteresis is provided between the voltage and the voltage. That is, a predetermined voltage difference is provided between the reference voltage when the second switching element 42 is turned on from off and the reference voltage when the second switching element 42 is turned on from off. Is stable. In this embodiment, the charge stop voltage is set to a voltage higher than the charge start voltage, but the charge stop voltage and the charge start voltage may be set to the same voltage.

The voltage detection unit 50 is a hysteresis comparator circuit using an operational amplifier, for example, and the operational amplifier operates with the power supply voltage V1 of the power storage unit 30. When the power supply voltage V1 of the power storage unit 30 exceeds the voltage at which the operational amplifier can operate, the voltage detection unit 50 starts operating. From the point in time when power is supplied to the switch 1, the voltage detection unit 50 starts operating. This time is shorter than that of a microcomputer that requires processing such as initialization.

The abnormality detection unit 60 includes a signal processing unit 61 configured by an integrated circuit, a current transformer 62 that is a zero-phase current transformer, a resistor 63, a diode circuit 64, and a low-pass filter 65.

The current transformer 62 includes a core 62a and an output winding 62b provided on the core 62a. The core 62a is formed in an annular shape from a ferromagnetic material such as ferrite.

Conductive members

4R, 4S, 4T, and 4N electrically connected to the four

electric paths

2R, 2S, 2T, and 2N are inserted into the core 62a. If any of the four electric paths 2 is grounded, an unbalance occurs between the currents flowing through the

conductive members

4R, 4S, 4T, and 4N penetrating the core 62a, and a current flows through the output winding 62b.

The resistor 63 is electrically connected between both ends of the output winding 62b of the current transformer 62. Between both ends of the resistor 63, an output voltage V2 having a voltage value proportional to the magnitude of the current flowing through the output winding 62b is generated.

The diode circuit 64 includes two diodes connected in parallel with the resistor 63. The two diodes included in the diode circuit 64 are connected in opposite directions. The two diodes of the diode circuit 64 flow current only in one direction from the anode to the cathode only when the voltage is equal to or higher than a predetermined forward voltage (slice voltage, for example, 1 V). Therefore, when the output voltage V2 of the current transformer 62 is lower than the forward voltage of the diode, such as normal leakage, the diode circuit 64 does not pass current. Further, when the output voltage V2 of the current transformer 62 becomes higher than the forward voltage of the diode, such as a heavy ground fault or a lightning surge, a current flows through the diode of the diode circuit 64. As a result, in the case of a heavy ground fault or a lightning surge, the voltage input to the signal processing unit 61 becomes lower than the output voltage V2 of the current transformer 62.

The low pass filter 65 is composed of a resistor and a capacitor. The voltage across the resistor 63 (the output voltage of the current transformer 62) V2 is input to the signal processing unit 61 via the low-pass filter 65. The low-pass filter 65 passes a signal component below a predetermined cutoff frequency and attenuates a signal component (noise component) having a frequency higher than the cutoff frequency. Therefore, the noise component input to the signal processing unit 61 by the low-pass filter 65. Is suppressed.

The signal processing unit 61 controls the thyristor 70 based on the output voltage V2 of the current transformer 62. Here, between the DC output terminals of the full-wave rectifiers 11 and 12, the solenoid coil 5a, the diode 71, and the thyristor 70 are electrically connected in series. A snubber circuit 72 composed of a resistor and a capacitor is connected between both ends of the thyristor 70.

If the output voltage V2 of the current transformer 62 is equal to or lower than a predetermined threshold voltage, the signal processing unit 61 determines that the leakage current is not flowing and turns off the thyristor 70. If the thyristor 70 is off, the current flowing through the solenoid coil 5a is smaller than the current value required to turn the contact 5b from on to off, and the contact 5b is turned on. Therefore, AC power is supplied from the AC power supply 3 to the load side via the switch 1.

When the output voltage V2 of the current transformer 62 exceeds a predetermined threshold voltage, the signal processing unit 61 determines that a leakage current has flowed and turns on the thyristor 70. When the thyristor 70 is turned on and the current flowing through the solenoid coil 5a becomes larger than the current value required to turn the contact 5b from on to off, the iron core is driven by the electromagnetic force of the solenoid coil 5a, and the contact 5b is driven by the iron core. The opening / closing mechanism is driven. As a result, the contact 5b is turned off, and the power supply from the AC power supply 3 to the load is interrupted.

Further, the conductive member 13 is inserted into the core 62a of the current transformer 62 in order to generate a pseudo unbalanced state. One end of the conductive member 13 is electrically connected to the N-phase conductive member 4N. The other end of the conductive member 13 is electrically connected to the R-phase conductive member 4 </ b> R via an operation check switch 14 and a resistor 15.

(2) Explanation of operation Below, the operation | movement of the electric circuit abnormality detection apparatus 10 and the switch 1 of this embodiment is demonstrated.

(2.1) Operation of the power circuit section When the electric circuit 2 is connected to the switch 1 and the AC power from the AC power supply 3 is supplied to the switch 1, the DC output terminals of the full-wave rectifiers 11 and 12 are connected. A pulsating voltage generated by full-wave rectification of the AC voltage from the AC power supply 3 is generated. Here, when the thyristor 70 is in an off state, the current necessary for turning off the contact 5b does not flow through the solenoid coil 5a, and the contact 5b is turned on.

When the voltage of the input terminal 21a of the power supply circuit unit 20 increases due to the pulsating voltage generated between the DC output terminals of the full-wave rectifiers 11 and 12, and the voltage level of the gate electrode of the first switching element 41 exceeds the threshold voltage. The first switching element 41 is turned on. When the first switching element 41 is turned on, a charging current flows through the power storage unit 30 and the voltage across the power storage unit 30 (power supply voltage V1) increases.

The voltage across the power storage unit 30 (power supply voltage V1) is output to the voltage detection unit 50 and the abnormality detection unit 60.

When the voltage value of the power supply voltage V1 exceeds a voltage value necessary for the abnormality detection unit 60 to operate, the abnormality detection unit 60 starts operating.

In addition, when the voltage value of the power supply voltage V1 exceeds the minimum value of the voltage range in which the voltage detection unit 50 can operate, the voltage detection unit 50 starts operation, and the voltage value of the power supply voltage V1 of the power storage unit 30 and a predetermined value The level is compared with the reference voltage (charge stop voltage and charge start voltage).

If the voltage value of power supply voltage V1 is equal to or lower than the charging stop voltage, voltage detection unit 50 turns off second switching element 42 and turns on first switching element 41 to charge power storage unit 30 with the state of power storage unit 30. The charging state is such that a current flows. At this time, when a charging current flows through the power storage unit 30, the voltage (power supply voltage V1) at both ends of the power storage unit 30 gradually increases.

When the voltage value of the power supply voltage V1 exceeds the charge stop voltage, the voltage detection unit 50 outputs a control signal having a voltage value higher than the threshold voltage to the gate electrode of the second switching element 42, turn on. When the second switching element 42 is turned on, the first switching element 41 is turned off, and a charging stop state in which a charging current does not flow to the power storage unit 30 is entered. When the power storage unit 30 is discharged and operating power is supplied to the abnormality detection unit 60 in a charging stop state in which the charging current does not flow to the power storage unit 30, the voltage (power supply voltage V1) across the power storage unit 30 gradually increases. descend.

Thereafter, when the power supply voltage V1 of the power storage unit 30 becomes equal to or lower than the charging start voltage, the voltage detection unit 50 turns off the second switching element 42. At this time, when the voltage value of the input terminal 21a exceeds the threshold voltage of the first switching element 41, the first switching element 41 is turned on, and the state of the power storage unit 30 is in the charged state. In the charged state, a charging current flows through the power storage unit 30, and the power supply voltage V1 of the power storage unit 30 gradually increases.

When the power supply circuit unit 20 repeats the operation as described above, the voltage (power supply voltage V1) charged in the power storage unit 30 is controlled between the charge start voltage and the charge stop voltage, and the abnormality detection unit 60 can operate. A power supply voltage V1 is supplied to the abnormality detection unit 60.

As described above, in this embodiment, the switch unit 40 is controlled to be in either the charged state or the charging stopped state based on the power supply voltage V1 of the power storage unit 30 detected by the voltage detecting unit 50, thereby detecting an abnormality. The power supply voltage V1 at which the unit 60 can operate is supplied to the abnormality detection unit 60. Therefore, compared to a case where the power supply circuit unit is configured by a circuit that steps down the input voltage with a resistor, power loss is reduced and heat generation of the power supply circuit unit 20 can be suppressed.

The switch 1 is also required to be downsized. However, when the switch 1 is downsized, the cross-sectional area of the conductive member 4 becomes small, so that the internal temperature of the switch 1 can rise due to the temperature rise of the conductive member 4. There is sex. In the switch 1 provided with the power supply circuit unit 20 according to the present embodiment, since the heat generation of the power supply circuit unit 20 is suppressed, an increase in the internal temperature of the switch 1 is suppressed and the switch 1 is downsized. Can do.

Further, when the switch 1 has an overcurrent protection function, a bimetal is connected in the middle of the conductive member 4. And when a bimetal curves by the Joule heat which generate | occur | produces when an overcurrent flows into the electrically-conductive member 4, a bimetal will move an opening-and-closing mechanism, and it is comprised so that the contact 5b may be turned off. In the switch 1 having an overcurrent protection function, when the internal temperature of the switch 1 rises due to heat generated by the power supply circuit unit 20, the current value when the bimetal moves the switch mechanism to turn off the contact 5b may vary. is there. When the power supply circuit unit 20 of the present embodiment is applied to the switch 1 having such an overcurrent protection function, an increase in the internal temperature of the switch 1 is suppressed by suppressing heat generation of the power supply circuit unit 20. Is done. Therefore, it is possible to reduce variations in the current value when the bimetal turns off the contact 5b.

Also, in the case where the power supply circuit unit is a circuit that steps down the input voltage with a resistor, if the input voltage is too low, the current flowing through the resistor may be reduced, and a sufficient output may not be obtained. In contrast, in the power supply circuit unit 20 of the present embodiment, a desired output can be obtained by charging the power storage unit 30 even when the input voltage is low.

In addition, when AC power is supplied to the switch 1, a charging current flows to the power storage unit 30 via the first switching element 41, and therefore, the power storage unit 30 compared to a switching power supply circuit including a control circuit that requires a power source. There is also an advantage that the rise of the power supply voltage V1 is accelerated.

Further, the switching period of the first switching element 41 and the second switching element 42 is about several tens of Hz, and the switching frequency is lower than that of a general switching power supply circuit, so that loss due to switching can be reduced.

(2.2) Operation of Abnormality Detection Unit When the power supply voltage V1 at which the abnormality detection unit 60 can operate is output from the power supply circuit unit 20 to the abnormality detection unit 60, the abnormality detection unit 60 detects an abnormality in the electric circuit 2 to be detected. The operation of detecting the presence or absence of is performed.

The abnormality detection unit 60 detects whether or not a leakage state in which a leakage current flows in the electric circuit 2 has occurred.

In the state where the leakage current is not flowing, the output voltage V2 of the current transformer 62 is lower than the threshold voltage, so the signal processing unit 61 turns off the thyristor 70. At this time, since the current value of the current flowing through the solenoid coil 5a is smaller than the current value required to turn the contact 5b from on to off, the contact 5b is turned on, and the switch 1 supplies the AC power to the load. The supply is not shut off.

On the other hand, if one of the electric circuits 2 is grounded and a leakage current flows, the current flowing through the electric circuit 2 becomes unbalanced and the output voltage V2 of the current transformer 62 becomes equal to or higher than the threshold voltage. The unit 61 turns on the thyristor 70. At this time, since the current value of the current flowing through the solenoid coil 5a is equal to or greater than the current value necessary to turn the contact 5b from on to off, the contact 5b is turned off, and the switch 1 supplies the AC power to the load. Shut off the supply.

Thus, since the switch 1 of this embodiment turns off the contact 5b when the abnormality detection unit 60 detects that there is an abnormality, the power supply to the load can be cut off.

(3) Modifications The following is a list of electric circuit abnormality detection devices and switches provided with the same according to modifications of the above embodiment. In addition, each structure of the modified example demonstrated below is applicable in combination with each structure demonstrated in the said embodiment suitably.

(3.1) Modification 1
In the above embodiment, as shown in FIG. 2, a resistor 34 as a second impedance element may be electrically connected between the first switching element 41 and the power storage unit 30. Since the resistor 34 is electrically connected between the first switching element 41 and the power storage unit 30, the charging current flowing through the power storage unit 30 is limited by the resistor 34. Therefore, when the first switching element 41 is switched from off to on, it is possible to suppress a sudden increase in the current flowing through the power storage unit 30. In the circuit example of FIG. 2, the second impedance element is the resistor 34, but it may be a circuit component (eg, a thermistor) having a predetermined impedance.

In the above embodiment, as shown in FIG. 2, the low-pass filter 51 is electrically connected between the output terminal of the voltage detector 50 and the control terminal (gate electrode) of the second switching element 42. Also good. The low-pass filter 51 can reduce a noise component flowing out from the voltage detection unit 50 to the input terminal unit 21 via the second switching element 42. Here, the low-pass filter 51 shown in FIG. 2 is an RC filter circuit composed of a resistor and a capacitor. However, other circuit configurations may be used as long as a predetermined cut-off frequency can be obtained.

(3.2) Modification 2
In the above-described embodiment and Modification 1, the switch unit 40 may be configured by one switching element 43 as shown in FIG.

The switching element 43 is an N-channel enhancement type MOSFET. The drain electrode of the switching element 43 is electrically connected to the input terminal 21a. The power storage unit 30 is electrically connected between the source electrode of the switching element 43 and the input terminal 21b. A resistor 31 is electrically connected between the drain electrode and the gate electrode of the switching element 43. The gate electrode of the switching element 43 is electrically connected to the output terminal of the voltage detection unit 50.

Here, the operation of the power supply circuit unit 20 will be described.

When the electric circuit 2 is connected to the switch 1 and the AC power from the AC power supply 3 is supplied to the switch 1, the AC voltage from the AC power supply 3 is applied to the full-wave between the DC output terminals of the full-wave rectifiers 11 and 12. A rectified pulsating voltage is generated. Here, when the thyristor 70 is in an off state, the current necessary for turning off the contact 5b does not flow through the solenoid coil 5a, and the contact 5b is turned on.

When the voltage of the input terminal 21a of the power supply circuit unit 20 increases due to the pulsating voltage generated between the DC output terminals of the full-wave rectifiers 11 and 12, and the voltage level of the gate electrode of the switching element 43 exceeds the threshold voltage, switching occurs. Element 43 is turned on. Here, the output of the voltage detection unit 50 is, for example, an open collector output. If the voltage value of the power supply voltage V1 is equal to or lower than the charge stop voltage, the output terminal of the voltage detection unit 50 is in an open state.

When the switching element 43 is turned on, a charging current flows through the power storage unit 30 and the voltage across the power storage unit 30 (power supply voltage V1) increases.

Thereafter, when the voltage value of the power supply voltage V1 exceeds the charge stop voltage, the output terminal of the voltage detection unit 50 is short-circuited to the ground, and the switching element 43 is turned off. As a result, switch unit 40 is controlled to place power storage unit 30 in a charge stop state, and power supply voltage V1 of power storage unit 30 gradually decreases.

After that, when the voltage value of the power supply voltage V1 falls below the charging start voltage, the output terminal of the voltage detection unit 50 is in an open state. Therefore, if the voltage value of the gate electrode of the switching element 43 becomes a voltage value higher than the threshold voltage. The switching element 43 is turned on. Thereby, the switch unit 40 is controlled so as to put the power storage unit 30 in a charged state, that is, the control unit (voltage detection unit 50) controls the switch unit 40 so as to put the power storage unit 30 in a charged state. The power supply voltage V1 of the unit 30 gradually increases.

(3.3) Other Modifications In the above embodiment and Modification 1, each of the first switching element 41 and the second switching element 42 is a MOSFET, but may be a semiconductor switching element such as a bipolar transistor.

In the above-described embodiment and Modification 1, the first impedance element connected in series with the second switching element 42 is the resistor 31, but may be a circuit component (for example, a thermistor) having a predetermined impedance.

In the above embodiment and

Modifications

1 and 2, the abnormality detection unit 60 detects a state in which a leakage current flows in the electric circuit 2, but the detection target of the abnormality detection unit 60 is not limited to the electric leakage in the electric circuit 2.

The abnormality detection unit 60 may detect an overvoltage generated due to a phase failure of the neutral wire as an abnormality in the electric circuit 2. If the neutral wire is missing, excessive voltage between R phase and N phase, between S phase and N phase, or between T phase and N phase due to imbalance of the load connected to R phase, S phase, and T phase. May occur. The abnormality detection unit 60 monitors the voltage between the R phase and the N phase, between the S phase and the N phase, and between the T phase and the N phase, and turns on the thyristor 70 when the voltage of each phase exceeds a predetermined upper limit value. Turn off 5b. Thereby, the abnormality detection unit 60 can detect an overvoltage state in which the voltage of the electric circuit 2 to be detected exceeds a predetermined upper limit value as an abnormality of the electric circuit 2.

Further, the abnormality detection unit 60 may detect a low voltage state in which the voltage of the electric circuit 2 to be detected is lower than a predetermined lower limit value as an abnormality of the electric circuit 2. The AC voltage supplied from the AC power supply 3 may fluctuate, and the operation of the load becomes unstable when the AC voltage supplied from the AC power supply 3 drops below the voltage necessary for the load to operate. there is a possibility. Here, the abnormality detection unit 60 monitors the voltage between the R phase and the N phase, between the S phase and the N phase, and between the T phase and the N phase, and turns off the thyristor 70 when the voltage of each phase falls below a predetermined lower limit value. Thus, the contact 5b may be turned off. Thereby, the abnormality detection part 60 can detect the low voltage state in which the voltage of the electric circuit 2 to be detected is lower than a predetermined lower limit as an abnormality of the electric circuit 2.

(4) Summary As described above, the electric circuit abnormality detection device (10) according to the first aspect includes an abnormality detection unit (60) that detects whether there is an abnormality in the electric circuit (2) to be detected, and an abnormality detection unit ( 60) and a power supply circuit section (20) for outputting a power supply voltage. The power supply circuit unit (20) includes an input terminal unit (21), a power storage unit (30), an output terminal unit (22), a switch unit (40), a voltage detection unit (50), and a control unit (50). ). The electric circuit 2 to be detected is electrically connected to the input terminal portion (21). The power storage unit (30) is charged by a DC voltage input to the input terminal unit (21). The abnormality detection unit (60) is electrically connected to the output terminal unit (22). The output terminal unit (22) is a terminal unit for outputting the voltage charged in the power storage unit (30) to the abnormality detection unit (60) as the power supply voltage (V1). The switch unit (40) changes the state of the power storage unit (30) between a charge state in which a charging current flows from the electric circuit (2) to be detected to the power storage unit (30) via the input terminal unit (21) and the power storage unit (30). ) Is switched to one of the charge stop states where no charge current flows. The voltage detector (50) detects the power supply voltage (V1) output from the power storage unit (30) to the abnormality detector (60). The control unit (50) controls the switch unit (40) according to the detection result of the voltage detection unit (50).

As described above, the switch unit (40) switches the state of the power storage unit (30) to either the charged state or the charge stop state according to the detection result of the voltage detection unit (50), so that the power storage unit (30 ) Is charging. Therefore, the electric circuit abnormality detection device (10) can reduce the power loss as compared with the case where the input voltage is stepped down by the resistor, and can suppress the temperature rise of the power supply circuit unit (20).

In the electric circuit abnormality detection device (10) of the second aspect, in the first aspect, when the power supply voltage (V1) detected by the voltage detection part (50) exceeds the charge stop voltage in the control part (50), The switch unit (40) is controlled so that the state of the power storage unit (30) is set to the charge stop state.

Thus, when the power supply voltage (V1) exceeds the charge stop voltage, the state of the power storage unit (30) is controlled to the charge stop state, so the power supply voltage (V1) of the power storage unit (30) is equal to or lower than the charge stop voltage. Can be controlled.

In the electric circuit abnormality detection device (10) of the third aspect, in the first or second aspect, the switch unit (40) includes the first switching element (41) and the second switching element (42). The first switching element (41) is electrically connected in series with the power storage unit (30) between the input terminal parts (21), and the second switching element (42) controls the first switching element (41). Electrically connected to the terminal. When one of the first switching element (41) and the second switching element (42) is turned on, the controller (50) turns off the other of the first switching element (41) and the second switching element (42). Thus, the switch unit (40) is controlled.

As a result, the control unit (50) controls the second switching element (42), thereby controlling the first switching element (41) electrically connected directly to the power storage unit (30). The state of 30) can be switched to either the charged state or the charged stop state.

In the electric circuit abnormality detection device (10) of the fourth mode, in the third mode, the power storage unit (30) and the first switching element (41) are electrically connected in series between the input terminal unit (21). Has been. When the power supply voltage (V1) detected by the voltage detection unit (50) is equal to or lower than the charging start voltage, the control unit (50) switches the switch unit (40) so that the second switching element (42) is turned off. Control.

Accordingly, if the power supply voltage (V1) is equal to or lower than the charging start voltage, the second switching element (42) is turned off and the first switching element (41) is turned on, so that the state of the power storage unit (30) Can be charged.

In the electric circuit abnormality detection device (10) according to the fifth aspect, in the third aspect, the first impedance element (31) and the second switching element (42) are electrically connected in series between the input terminal portions (21). Connected to. A control terminal (gate electrode) of the first switching element (41) is electrically connected to a connection point between the first impedance element (31) and the second switching element (42). When the power supply voltage (V1) detected by the voltage detector (50) exceeds the charge stop voltage, the control unit (50) turns on the second switching element (42), and the power supply voltage (V1) starts charging. If it is below the voltage, the switch unit (40) is controlled so that the second switching element (42) is turned off.

Thereby, when the power supply voltage (V1) exceeds the charge stop voltage, the power storage unit (30) is brought into a charge stop state, and when the power supply voltage (V1) becomes equal to or lower than the charge start voltage, the power storage unit (30) is put into a charge state. be able to. In the charge stop state, since the current flows to the second switching element (42) via the first impedance element (31), the current flowing to the second switching element (42) is reduced by the first impedance element (31). Can do. Therefore, power consumption can be reduced and temperature rise in the power supply circuit section (20) can be suppressed.

In the electric circuit abnormality detection device (10) according to the sixth aspect, in any one of the third to fifth aspects, the power supply circuit unit (20) includes the first switching element (41) and the power storage unit (30). A second impedance element (34) electrically connected therebetween is further provided.

As a result, when the first switching element (41) is turned from off to on, the charging current flowing through the power storage unit (30) is reduced by the second impedance element (34). Current can be prevented from flowing into the.

In the electric circuit abnormality detection device (10) of the seventh aspect, in any one of the third to sixth aspects, the voltage detection unit (50) also functions as a control unit. A voltage detection part (50) outputs the control signal which controls a 2nd switching element (42) according to the detection result of a power supply voltage (V1). The power supply circuit unit (20) may further include a low-pass filter (51) electrically connected between the voltage detection unit (50) and the control terminal of the second switching element (42).

Thereby, the noise component flowing out from the voltage detection unit 50 to the input terminal unit (21) via the second switching element (42) can be reduced by the low-pass filter (51).

In the electric circuit abnormality detection device (10) of the eighth aspect, in any one of the first to seventh aspects, an abnormality detected by the abnormality detection unit (60) is detected as a leakage current in the electric circuit (2) to be detected. At least one of a flowing state, an overvoltage state, and an undervoltage state. Here, the overvoltage state is a state in which the voltage of the electric circuit (2) to be detected exceeds the upper limit value, and the low voltage state is a state in which the voltage of the electric circuit 2 to be detected is lower than the lower limit value.

For example, when a neutral wire phase loss occurs, the voltage of the electric circuit 2 of each phase may be double the normal voltage. Moreover, the voltage of the electric circuit (2) of each phase may be insufficient due to an abnormality in the AC power supply (3). According to the eighth aspect, the abnormality detection unit (60) can detect at least one of a state in which a leakage current flows in the electric circuit (2) to be detected, an overvoltage state, and a constant voltage state.

The switch (1) according to the ninth aspect includes an electric circuit abnormality detecting device (10) according to any one of the first to eighth aspects, and a power switch (10) electrically connected to the electric circuit (2) to be detected. 5b). The power switch (5b) is controlled by the electric circuit abnormality detection device (10) based on the detection result of the abnormality detection unit (60).

Thereby, the switch (1) which suppressed the heat_generation | fever of a power supply circuit part (20) can be provided.

1

Switch

2, 2R, 2S, 2T, 2N Electric circuit 5b Relay contact (power switch)
DESCRIPTION OF SYMBOLS 10 Electric circuit abnormality detection apparatus 20 Power supply circuit part 21 Input terminal part 22 Output terminal part 30 Power storage part 31 Resistor (1st impedance element)
34 Resistor (second impedance element)
40 switch part 41 1st switching element 42 2nd switching element 43 switching element 50 Voltage detection part (control part)
51 Low-pass filter 60 Abnormality detection unit

Claims

An abnormality detection unit that detects the presence or absence of abnormality in the electric circuit to be detected, and a power supply circuit unit that outputs a power supply voltage to the abnormality detection unit,
The power supply circuit unit is
An input terminal portion to which the electric circuit to be detected is electrically connected;
A power storage unit charged by a DC voltage input to the input terminal unit;
An output terminal unit for electrically connecting the abnormality detection unit and outputting the voltage charged in the power storage unit to the abnormality detection unit as the power supply voltage;
A switch for switching the state of the power storage unit between a charging state in which a charging current flows from the electric circuit to be detected to the power storage unit via the input terminal unit and a charging stop state in which a charging current does not flow to the power storage unit And
A voltage detection unit for detecting the power supply voltage output from the power storage unit to the abnormality detection unit;
And a control unit that controls the switch unit according to a detection result of the voltage detection unit.
The said control part controls the said switch part to make the state of the said electrical storage part into the said charge stop state, if the said power supply voltage detected by the said voltage detection part exceeds a charge stop voltage. Item 6. An electric circuit abnormality detection device according to Item 1.
A first switching element electrically connected in series with the power storage unit between the input terminal parts; a second switching element electrically connected to a control terminal of the first switching element; With
The control unit controls the switch unit such that when one of the first switching element and the second switching element is turned on, the other of the first switching element and the second switching element is turned off. The electric circuit abnormality detection device according to claim 1 or 2, characterized by the above-mentioned.
The power storage unit and the first switching element are electrically connected in series between the input terminal units,
The said control part controls the said switch part so that a said 2nd switching element may be turned off, if the said power supply voltage detected by the said voltage detection part is below a charging start voltage. An electrical circuit abnormality detection device according to claim 1.
The first impedance element and the second switching element are electrically connected in series between the input terminal portions,
A control terminal of the first switching element is electrically connected to a connection point between the first impedance element and the second switching element;
The control unit controls the second switching element to be turned on when the power supply voltage detected by the voltage detection unit exceeds a charge stop voltage, and the power supply voltage detected by the voltage detection unit is The electric circuit abnormality detection device according to claim 3, wherein the switch unit is controlled so that the second switching element is turned off when the voltage is equal to or lower than a charging start voltage.
6. The power supply circuit unit according to claim 3, further comprising a second impedance element electrically connected between the first switching element and the power storage unit. Electric circuit abnormality detection device.
The voltage detection unit also functions as the control unit,
The voltage detection unit outputs a control signal for controlling the second switching element according to the detection result of the power supply voltage,
The power supply circuit unit further comprises a low-pass filter electrically connected between the voltage detection unit and a control terminal of the second switching element. An electrical circuit abnormality detection device according to claim 1.
The abnormality detected by the abnormality detection unit is a state in which a leakage current flows in the detection target circuit, an overvoltage state in which the voltage of the detection target circuit exceeds an upper limit value, and a voltage of the detection target circuit is below a lower limit value The electric circuit abnormality detection device according to any one of claims 1 to 7, wherein the electric circuit abnormality detection device is at least one of a low voltage state.
An electric circuit abnormality detection device according to any one of claims 1 to 8, and a power switch electrically connected to the electric circuit to be detected,
The power switch is controlled based on a detection result of the abnormality detection unit by the electric circuit abnormality detection device.