CN-224218107-U - Leakage circuit breaker

CN224218107UCN 224218107 UCN224218107 UCN 224218107UCN-224218107-U

Abstract

The application discloses an electric leakage circuit breaker which comprises a zero sequence transformer TA, a limiting circuit, an impedance matching circuit, a voltage doubling integral energy storage circuit, a voltage detection circuit, a tripping circuit and an anti-surge circuit, wherein the zero sequence transformer TA is sleeved on a main circuit and used for inducing leakage current, the voltage doubling integral energy storage circuit is used for doubling and superposing input voltage to provide comparison signals for the voltage detection circuit and tripping energy for the tripping circuit, the voltage detection circuit is connected with the tripping circuit, when the comparison signals reach the set value of the voltage detection circuit, the voltage detection circuit is used for conducting the tripping circuit to enable the tripping circuit to work, the anti-surge circuit is connected to the voltage doubling integral energy storage circuit, and when the induced current generated by surge current is larger than the set value of the anti-surge circuit, the anti-surge circuit is conducted to limit the voltage superposition of the voltage doubling integral energy storage circuit, so that the comparison signals are lower than the set value of the voltage detection circuit, and the electric leakage circuit has the characteristic of preventing misoperation of products due to surge.

Inventors

YANG KUI
LAN YUNSHENG
PU QIUBAO
LI CHAOJIE

Assignees

浙江九策智能电气有限公司

Dates

Publication Date: 20260508
Application Date: 20250528

Claims (10)

1. The leakage circuit breaker is characterized by comprising a zero sequence transformer TA, an amplitude limiting circuit, an impedance matching circuit, a voltage doubling integral energy storage circuit, a voltage detection circuit, a tripping circuit and an anti-surge circuit, wherein the zero sequence transformer TA is sleeved on a main circuit and used for inducing leakage current, the amplitude limiting circuit and the impedance matching circuit are connected with the secondary side of the zero sequence transformer TA, signals induced by the transformer TA are limited and modulated and then are transmitted to the voltage doubling integral energy storage circuit, the voltage doubling integral energy storage circuit is connected with the impedance matching circuit, the voltage detection circuit and the tripping circuit, the voltage doubling integral energy storage circuit performs voltage doubling superposition on the input voltage, provides comparison signals for the voltage detection circuit and provides tripping energy for the tripping circuit, the voltage detection circuit is connected with the tripping circuit, when the comparison signals reach a set value of the voltage detection circuit, the voltage detection circuit is conducted to enable the tripping circuit to work, the anti-surge circuit is connected on the voltage doubling integral energy storage circuit, and when induction currents generated due to the surge currents occur, the anti-surge circuit is conducted to limit voltage superposition of the voltage doubling integral energy storage circuit, and therefore the comparison signals are lower than the set value of the voltage detection circuit.
2. The leakage circuit breaker according to claim 1, wherein the impedance matching circuit comprises a capacitor C1 and a resistor R1, and the capacitor C1 and the resistor R1 are connected in parallel on the secondary side of the zero sequence transformer TA; Or, the impedance matching circuit comprises a capacitor C1, and the capacitor C1 is connected in parallel with the secondary side of the zero sequence transformer TA.
3. A leakage breaker according to claim 1, wherein the limiting circuit is a transient suppression diode D1 or a discharge tube or a varistor, and the transient suppression diode D1 or the discharge tube or the varistor is connected in parallel to the secondary side of the zero sequence transformer TA.
4. The leakage circuit breaker of claim 1, wherein the voltage doubling integrating energy storage circuit comprises a resistor R2, a resistor R3, a diode D2, a diode D3, a capacitor C2 and a capacitor C3, wherein a first end of the resistor R2 is connected with a first end of the capacitor C1, a second end of the resistor R2 is connected with an anode of the diode D2, a cathode of the diode D2 is connected with a first end of the capacitor C2, a first end of the resistor R3 is connected with a second end of the capacitor C1, a second end of the resistor R3 is respectively connected with a second end of the capacitor C2 and a first end of the capacitor C3, a second end of the capacitor C3 is connected with an anode of the diode D3, a cathode of the diode D3 is connected with an anode of the diode D1, a signal induced by a mutual inductor TA charges the capacitor C2 in a positive half period of leakage current, and a signal induced by the mutual inductor TA charges the capacitor C3 in a negative half period of the leakage current.
5. A leakage breaker according to claim 1, wherein the anti-surge circuit comprises two first electronic switches, the two first electronic switches are connected with the voltage doubling integral energy storage circuit, after the first electronic switches are conducted, charging of the voltage doubling integral energy storage circuit is limited, one first electronic switch is conducted when surge current induction occurs in a positive half cycle, and the other first electronic switch is conducted when surge current induction occurs in a negative half cycle.
6. The leakage breaker of claim 5, wherein the two first electronic switches are PNP type transistors and ‌ NPN type transistors, respectively, or the two first electronic switches are N channel MOS transistors and P channel MOS transistors, respectively.
7. A leakage breaker according to claim 4, wherein the anti-surge circuit comprises a triode Q1 and a triode Q2, wherein a base electrode of the triode Q1 is respectively connected with a second end of a capacitor C2 and a second end of a resistor R3, a collector electrode of the triode Q1 is respectively connected with a first end of the capacitor C2 and a cathode electrode of a diode D2, an emitter electrode of the triode Q1 is respectively connected with the second end of the capacitor C1 and the first end of the resistor R3, a base electrode of the triode Q2 is respectively connected with the first end of the capacitor C3 and the second end of the resistor R3, an emitter electrode of the triode Q2 is respectively connected with the first end of the resistor R3 and a second end of the capacitor C1, a collector electrode of the triode Q2 is respectively connected with the second end of the capacitor C3 and an anode electrode of the diode D3, the triode Q1 is conducted to limit charging of the capacitor C2 when surge current induction current occurs in a positive half cycle, and the triode Q2 is conducted to limit charging of the capacitor C3 when surge current induction current occurs in a negative half cycle.
8. The leakage circuit breaker according to claim 1, wherein the voltage detection circuit comprises a diode D4, a capacitor C4 and a voltage detector U1, wherein the positive electrode of the diode D4 is connected with a voltage doubling integral energy storage circuit, the positive electrode of the diode D4 is connected with a first end of the capacitor C4 and a Vin pin of the voltage detector U1, a second end of the capacitor C4 is connected with a Vss pin of the voltage detector U1 and a driving tripping circuit, a Vout pin of the voltage detector U1 is connected with the driving tripping circuit, signals sensed by a mutual inductor TA charge the capacitor C4 after passing through the voltage doubling integral energy storage circuit in the positive half cycle and the negative half cycle of a leakage current, the comparison signals are voltages at two ends of the capacitor C4, and when the voltage detector U1 detects that the comparison signals are larger than a detector set value, the voltage detector U1 outputs the signals to drive the tripping circuit.
9. A leakage circuit breaker according to claim 1, wherein the trip circuit comprises a second electronic switch and a trip coil KM, the control terminal of the second electronic switch is connected to the Vout pin of the voltage detector U1, and the second electronic switch is connected in series with the trip coil KM.
10. The leakage breaker of claim 9, wherein the second electronic switch is a MOS transistor or a thyristor.

Description

Leakage circuit breaker Technical Field The application relates to the field of low-voltage electricity, in particular to an electric leakage breaker. Background The leakage protection circuit breaker is a protector for preventing personal electric shock accidents, is arranged in a power grid, and is used for disconnecting a circuit or sending out an alarm signal when the leakage in the power grid is larger than a set value, so that the personal safety and the circuit safety are ensured. The leakage protector is required to be releasable but not to be damaged under the clause of 9.19.2 verification of performance at 3000A surge current (8/20 mus surge current test) in national standard GB/T16917.1. However, if the rear stage has large-scale motors, large-scale capacitors and other devices or has the surge of large current in the application scene of induction lightning stroke and the like, users often do not hope that the tripping of the leakage protector causes the misoperation of the circuit, so that the surge-resistant leakage protector with the test item not tripped appears in the market. In order to resist surge, the leakage protection circuit structure of the existing leakage protection circuit breaker is as described in CN116667280a, CN207251174U and other documents, and a bidirectional suppressor diode D1 is connected in parallel to the secondary side of the zero sequence transformer, so that the circuit breaker can play a certain role in voltage suppression, but the circuit breaker is easy to trip when surge current actually occurs. Therefore, how to provide a leakage breaker that will not trip by mistake when an inrush current occurs is a valuable direction. Disclosure of Invention Therefore, the application aims to overcome the defects in the prior art, and aims to provide an electric leakage breaker which has the characteristic of preventing a product from tripping by mistake due to surge. The application provides an electric leakage breaker which comprises a zero sequence transformer TA, a limiting circuit, an impedance matching circuit, a voltage doubling integral energy storage circuit, a voltage detection circuit, a tripping circuit and an anti-surge circuit, wherein the zero sequence transformer TA is sleeved on a main circuit and used for inducing leakage current, the limiting circuit and the impedance matching circuit are connected with the secondary side of the zero sequence transformer TA, signals induced by the transformer TA are limited and modulated and then are transmitted to the voltage doubling integral energy storage circuit, the voltage doubling integral energy storage circuit is connected with the impedance matching circuit, the voltage detection circuit and the tripping circuit, the voltage doubling integral energy storage circuit performs voltage doubling superposition on input voltages, provides comparison signals for the voltage detection circuit and provides tripping energy for the tripping circuit, the voltage detection circuit is connected with the tripping circuit, when the comparison signals reach a set value of the voltage detection circuit, the voltage detection circuit is conducted to enable the tripping circuit to work, the anti-surge circuit is connected to the voltage doubling integral energy storage circuit, and when induced currents generated due to the surge currents occur, the anti-surge circuit is conducted to limit voltage superposition of the voltage doubling integral energy storage circuit, and therefore the comparison signals are lower than the set value of the voltage detection circuit. In some embodiments of the present application, the impedance matching circuit includes a capacitor C1 and a resistor R1, where the capacitor C1 and the resistor R1 are connected in parallel on the secondary side of the zero sequence transformer TA. In some embodiments of the present application, the impedance matching circuit includes a capacitor C1, and the capacitor C1 is connected in parallel to the secondary side of the zero sequence transformer TA. In some embodiments of the application, the limiter circuit is a transient suppression diode D1 or a discharge tube or a varistor, and the transient suppression diode D1 or the discharge tube or the varistor is connected in parallel to the secondary side of the zero sequence transformer TA. In some embodiments of the present application, the voltage doubling integrating tank circuit comprises a resistor R2, a resistor R3, a diode D2, a diode D3, a capacitor C2 and a capacitor C3, wherein a first end of the resistor R2 is connected with a first end of the capacitor C1, a second end of the resistor R2 is connected with a positive electrode of the diode D2, a negative electrode of the diode D2 is connected with a first end of the capacitor C2, a first end of the resistor R3 is connected with a second end of the capacitor C1, a second end of the resistor R3 is respectively connected with a second end of the capacitor C2 and