Portable Dual-line Leakage Protection Device

Abstract

The present invention discloses a portable double-line leakage protection device, which includes a housing made of flame-retardant material by pressing, a functional circuit board arranged inside the housing, a power input plug arranged on one side of the housing, and an output socket arranged on the other side. The functional circuit board includes an automatic zero-fire wire switching circuit, an intelligent ground wire module, and a leakage protection module. The automatic zero-fire wire switching circuit is connected to the intelligent ground wire module and the leakage protection module, and the leakage protection module and the intelligent ground wire module are connected to the output socket. The AC power supply with unknown wire sequence is accessed through the power input plug, and after passing through the automatic zero-fire switching circuit, it maintains a fixed zero-fire wire sequence. When the current difference between the zero-fire wire is greater than or equal to 30 mA, the leakage protection module immediately cuts off the circuit connection with the output socket. The intelligent ground wire module can automatically identify whether the power input plug is connected to the ground wire. When the ground wire is not detected, the automatic zero-fire switching circuit is automatically started to output the zero wire as an emergency ground wire, realizing the safety protection of residential electricity use.

Description

Technical Field

[0001] The present invention relates to the technical field of residential safe electricity use, and more specifically to a portable two-wire leakage protection device. Background Art

[0002] At present, China's national standard requires that residential electricity use implement a 220V single-phase three-wire system, that is, one neutral wire, one live wire and one ground wire. According to this requirement, for any electrical equipment with a metal shell, the shell will be directly connected to the ground wire. In cooperation with the leakage protection device, it can automatically trip when the electrical equipment leaks electricity, protecting personal safety. However, in real life, due to the actual situation in China, there are still a large number of non-standard two-wire power supply methods of one neutral wire and one live wire in many families (especially in areas such as the urban-rural fringe). The sockets under this power supply method not only do not have a ground wire, but also have the problem of incorrect connection of the neutral wire and the live wire. When using electrical appliances with metal shells in this environment, such as charging new energy vehicles or motorcycles, if the vehicle leaks electricity, the circuit will not be able to automatically protect, and in severe cases, it may even cause electric shock accidents, endangering the lives and safety of the people. Especially with the country's strong promotion of new energy vehicles, the sales volume of new energy vehicles has increased year by year, and more and more people have started to purchase and use new energy electric vehicles or electric motorcycles, etc., making this risk increase year by year.

[0003] Therefore, how to achieve automatic leakage protection in a single-phase two-wire power supply environment is an urgent problem to be solved by those skilled in the art. Summary of the Invention

[0004] In view of this, the present invention provides a portable two-wire leakage protection device, including a housing pressed from a flame-retardant material, a functional circuit board arranged inside the housing, a power input plug arranged on one side of the housing, and an output socket arranged on the other side. The functional circuit board includes an automatic neutral-live wire switching circuit, an intelligent ground wire module and a leakage protection module. The AC power supply with unknown wire sequence is connected through the power input plug on the left, and after passing through the automatic neutral-live wire switching circuit, it maintains a fixed neutral-live wire sequence; the leakage protection module is connected after the automatic neutral-live wire switching circuit, and the output socket is connected after the leakage protection module. When the current difference between the neutral wire and the live wire of the leakage protection module is greater than or equal to 30mA, it immediately cuts off the circuit connection with the output socket to achieve single-phase leakage protection; an intelligent ground wire module is arranged between the ground wire of the power input plug and the output socket, which can automatically identify whether the power input plug has a normal ground wire. If no ground wire is detected, it automatically activates the automatic neutral-live wire switching circuit to output the neutral wire as an emergency ground wire for use. Thus, the safe electricity use protection of residential household appliances, new energy electric vehicles, electric motorcycles, etc. is realized.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A portable double - line leakage protection device, comprising: a housing and a functional circuit board disposed within the housing; a power input plug is provided on one side of the housing, and an output socket is provided on the other side; the functional circuit board includes an automatic live - neutral switching circuit, an intelligent ground wire module, and a leakage protection module; the automatic live - neutral switching circuit is connected to the power input plug, the intelligent ground wire module, and the leakage protection module; the output socket is connected to the intelligent ground wire module and the leakage protection module.

[0007] Preferably, the power input plug is provided with AC inputs IN1, IN2 for connecting an external power supply and a ground wire input G - in.

[0008] Preferably, the automatic live - neutral switching circuit is provided with a touch point T1. When the input terminals AC220A and AC220B of the automatic live - neutral switching circuit are respectively connected to the AC inputs of the power input plug, and the user touches the touch point T1;

[0009] If AC220A is connected to the live wire and AC220B is connected to the neutral wire, then there is a current flowing through the loop formed by the touch point T1, resistor R4, triode Q4, and AC220A in sequence. At this time, the triode Q4 conducts, the light - emitting diode of the opto - coupler U1 lights up, the triode of the opto - coupler U1 conducts, pulling down pin 1 of the controller MCU. At the same time, the triode Q2 cannot conduct, the opto - coupler U2 does not conduct, and pin 8 of the controller MCU is at a high level; after the controller MCU detects that pin 1 is low and pin 8 is high, it determines that AC220A is connected to the live wire and AC220B is connected to the neutral wire. Pin 7 of the controller MCU outputs a low level, lighting up the line sequence indicator LEDL. At the same time, pin 5 outputs a low level and the relay J1 is attracted. At this time, the output port AC_OL of the output socket is the live wire, and the output port AC_ON is the neutral wire;

[0010] If AC220B is the live wire and AC220A is the neutral wire, then there is a current flowing through the loop formed by the touch point T1, resistor R1, triode Q2, and AC220B in sequence. At this time, the triode Q2 conducts, the light - emitting diode of the opto - coupler U2 lights up, the triode of the opto - coupler U2 conducts, pulling down pin 8 of the controller MCU. At the same time, the triode Q1 cannot conduct, the opto - coupler U1 does not conduct, and pin 1 of the controller MCU is at a high level; after the controller MCU detects that pin 8 is low and pin 1 is high, it determines that AC220B is connected to the live wire and AC220A is connected to the neutral wire. Pin 6 of the controller MCU outputs a low level, lighting up the line sequence indicator LEDN. At the same time, pin 5 outputs a high level, and the relay J1 is not attracted. At this time, the output port AC_OL of the output socket is the live wire, and the output port AC_ON is the neutral wire.

[0011] Preferably, in the default state of the intelligent ground wire module, the relay J2 does not actuate, and the input ground wire GND of the power input plug is directly connected to the AC_GND of the output socket.

[0012] After the controller MCU automatically switches the zero-fire wire sequence:

[0013] If the input ground wire GND is connected to the ground wire input, the live wire output by the automatic zero-fire wire switching circuit forms a current loop in sequence through the light-emitting diode of the optocoupler U4, the resistor R9, and the input ground wire GND. At this time, the secondary triode of the optocoupler U4 conducts, pulling down the 3rd pin of the controller MCU. After the controller MCU detects the low level of the 3rd pin, it determines that there is a ground wire at the input ground wire GND end. The controller MCU outputs a high level from the 4th pin, the relay J2 remains non-actuated, and the input ground wire GND is directly connected to the AC_GND.

[0014] If there is no such ground wire at the input ground wire GND end, the live wire output by the automatic zero-fire wire switching circuit cannot form a current loop in sequence through the optocoupler U4, the resistor R9, and the input ground wire GND. The optocoupler U4 does not conduct, the 3rd pin of the controller MCU is at a high level. After the controller MCU detects the high level of the 3rd pin, it determines that the input ground wire GND lacks the connection of the ground wire. The controller MCU outputs a low level from the 4th pin, the relay J2 is attracted, and the AC_GND is connected to the neutral wire output by the automatic zero-fire wire switching circuit, using the neutral wire to replace the ground wire emergently.

[0015] Preferably, the housing is made of an aluminum shell.

[0016] As can be seen from the above technical solutions, compared with the prior art, the present invention discloses a portable two-wire leakage protection device, which realizes line sequence conversion and automatic leakage protection in a one-zero-one-fire two-line power supply state. Assuming that there is no ground wire at the input end, the intelligent ground wire module will automatically enable the emergency grounding mode, using the neutral wire at the output end of the automatic zero-fire wire switching circuit as the emergency ground wire. If the device shell connected to the output socket is leaking electricity, the leaking current will pass through the device shell, via the ground wire of the output socket, bypass the leakage protection module and return to the neutral wire at the output end of the automatic zero-fire wire switching circuit, which will cause the currents of the two wires inside the leakage protection module to be different. Once this difference reaches more than 30 mA stipulated by the state, the leakage protection module will actuate, cutting off the circuit connection to the output socket, thereby shutting down the power supply of the device and achieving the purpose of leakage protection. Description of the Drawings

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on the provided drawings.

[0018] Figure 1 The attached drawing is a module structure diagram of a portable two-wire leakage protection device provided by the present invention;

[0019] Figure 2 The attached drawing is a circuit diagram of a portable two-wire leakage protection device provided by the present invention. Specific embodiments

[0020] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0021] The embodiment of the present invention discloses a portable two-wire leakage protection device, including: a housing and a functional circuit board arranged inside the housing; a power input plug is arranged on one side of the housing, and an output socket is arranged on the other side; the functional circuit board includes an automatic live-neutral wire switching circuit, an intelligent ground wire module, and a leakage protection module; the automatic live-neutral wire switching circuit is connected to the power input plug, the intelligent ground wire module, and the leakage protection module; the output socket is connected to the intelligent ground wire module and the leakage protection module.

[0022] To further optimize the above technical solution, the power input plug is provided with AC inputs IN1, IN2 for connecting an external power supply and a ground wire input G-in.

[0023] To further optimize the above technical solution, the automatic live-neutral wire switching circuit is provided with a touch point T1. When the AC220A and AC220B at the input end of the automatic live-neutral wire switching circuit are respectively connected to the AC inputs of the power input plug, the user touches the touch point T1;

[0024] If AC220A is connected to the live wire and AC220B is connected to the neutral wire, there will be a current passing through the loop formed by the touch point T1, resistor R4, triode Q4, and AC220A in sequence. At this time, the triode Q4 conducts, the light-emitting diode of the optocoupler U1 lights up, the triode of the optocoupler U1 conducts, pulling down pin 1 of the controller MCU. At the same time, the triode Q2 cannot conduct, the optocoupler U2 does not conduct, and pin 8 of the controller MCU is at a high level. After the controller MCU detects that pin 1 is low and pin 8 is high, it determines that AC220A is connected to the live wire and AC220B is connected to the neutral wire. The controller MCU outputs a low level at pin 7 to light up the line sequence indicator LEDL. At the same time, it outputs a low level at pin 5, and the relay J1 closes. At this time, the output port AC_OL of the output socket is the live wire, and the output port AC_ON is the neutral wire;

[0025] If AC220B is the live wire and AC220A is the neutral wire, there will be a current passing through the loop formed by the touch point T1, resistor R1, triode Q2, and AC220B in sequence. At this time, the triode Q2 conducts, the light-emitting diode of the optocoupler U2 lights up, the triode of the optocoupler U2 conducts, pulling down pin 8 of the controller MCU. At the same time, the triode Q1 cannot conduct, the optocoupler U1 does not conduct, and pin 1 of the controller MCU is at a high level. After the controller MCU detects that pin 8 is low and pin 1 is high, it determines that AC220B is connected to the live wire and AC220A is connected to the neutral wire. The controller MCU outputs a low level at pin 6 to light up the line sequence indicator LEDN. At the same time, it outputs a high level at pin 5, and the relay J1 does not close. At this time, the output port AC_OL of the output socket is the live wire, and the output port AC_ON is the neutral wire.

[0026] To further optimize the above technical solution, in the default case of the intelligent ground wire module, the relay J2 does not act, and the input ground wire GND of the power input plug is directly connected to the AC_GND of the output socket;

[0027] When the controller MCU automatically switches the zero-fire wire sequence:

[0028] If the input ground wire GND is connected to the ground wire input, the live wire output by the automatic zero-fire wire switching circuit forms a current loop through the light-emitting diode of the optocoupler U4, resistor R9, and the input ground wire GND in sequence. At this time, the secondary triode of the optocoupler U4 conducts, pulling down pin 3 of the controller MCU. After the controller MCU detects the low level of pin 3, it determines that there is a ground wire at the input ground wire GND end. The controller MCU outputs a high level at pin 4, and the relay J2 remains non-operational. The input ground wire GND is directly connected to the AC_GND;

[0029] If there is no ground wire at the input ground wire GND terminal, the live wire output by the automatic live-neutral switching circuit cannot form a current loop through the optocoupler U4, resistor R9, and the input ground wire GND in sequence. The optocoupler U4 is not turned on, and the 3rd pin of the controller MCU is at a high level. After the controller MCU detects the high level of the 3rd pin, it determines that the input ground wire GND lacks an access ground wire. The 4th pin of the controller MCU outputs a low level, the relay J2 is energized, and AC_GND is connected to the neutral wire output by the automatic live-neutral switching circuit, using the neutral wire to replace the ground wire emergently.

[0030] To further optimize the above technical solution, the leakage protection module is an existing conventional leakage protector.

[0031] To further optimize the above technical solution, the housing is made of aluminum shell, which is structurally firm and reliable and light in weight.

[0032] Embodiment

[0033] The power input plug of the portable two-wire leakage protection device includes AC input ports IN1 and IN2, and a ground wire input port G-in. The output socket includes a neutral wire output port N-OUT, a live wire output port L-OUT, and a ground wire GND.

[0034] The two input terminals of the automatic live-neutral switching module include AC220A and AC220B, and a touch point T1; its circuit components include resistors R1-R7, capacitors C1, C3, C4, diodes D2-D4, transistors Q2, Q4, optocouplers U1, U2, line sequence indicators LEDL, LEDN, a relay J1, and a controller MCU; AC220A is connected to the anode of the light-emitting diode of U2 through the series-connected D2 and R2, and AC220A is connected to the emitter of Q4 and a pin of J1. AC220B is connected to the anode of the light-emitting diode of U1 through the series-connected D3 and R3, and AC220B is connected to the emitter of Q2 and a pin; T1 is connected to the base of Q2 through R1 and to the base of Q4 through R4; the collector of the transistor of U2 is connected to the 8th pin of the MCU, C1, and one end of R5. The other end of C1 is grounded and connected to the emitter, and the other end of R5 is connected to the +5V power supply; the collector of the transistor of U1 is connected to the 1st pin of the MCU, C3, and one end of R6. The other end of C3 is grounded and connected to the emitter, and the other end of R6 is connected to the +5V power supply; the 7th pin of the MCU is connected to the cathode of LEDL, the 6th pin is connected to the cathode of LEDN, and the anodes of LEDL and LEDN are connected to the +5v power supply through R7; the 5th pin of the MCU is connected to the negative power supply pin of J1, D4 and C4 are connected in parallel between the 5th pin and the +5V power supply, and the +5V power supply is connected to the positive power supply pin of J1;

[0035] Another two pins of a group of switches in J1 connected to AC220A are respectively connected to pin 1 and pin 2 of the leakage protection module. For the group of switches connected to AC220A, the other two pins are respectively connected to pin 2 and pin 1 of the leakage protection module. Pin 3 of the leakage protection module is connected to N-OUT, and pin 4 is connected to L-OUT.

[0036] The intelligent ground wire module includes resistors R9, R10, capacitor C2, optocoupler U4 and relay J2. The ground wire input port G-in is connected to the cathode of the light-emitting diode of U4 and pin 4 of J2 through R9. The anode of the light-emitting diode of U4 is connected to pin 1 of the leakage protection module. The collector of the triode of U4 is connected to pin 3 of the MCU, C2 and one end of R10. The other end of C2 is grounded and connected to the emitter, and the other end of R10 is connected to the +5V power supply. The negative power supply pin 2 of J2 is connected to pin 4 of the MCU, the positive power supply pin 5 is connected to the +5V power supply, pin 4 is connected to G-in, pin 1 is connected to GND, and pin 2 is connected to pin 2 of the leakage protection module.

[0037] The use of the present invention does not require prior detection of the neutral wire and the live wire of the power supply socket. The user does not need to manually identify the neutral wire and the live wire. It has the function of intelligently identifying the neutral wire and the live wire and automatically switching to fix the wire sequence of the neutral wire and the live wire, ensuring that the output socket maintains the national standard of left zero and right fire. At the same time, when the power supply line is not properly grounded, as long as the shell of the electrical device charged by connecting the present invention leaks electricity to reach the national regulated protection current range (≥30 mA), the output power supply will be cut off within the national regulated time (≤0.1 second), realizing the automatic leakage protection of dual-line power supply and ensuring the personal safety of users.

[0038] In this specification, each embodiment is described in a progressive manner. The key point of each embodiment is to illustrate the differences from other embodiments. The same or similar parts among the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple. For the relevant parts, refer to the description of the method part.

[0039] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art. The general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown herein, but will be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A portable double - line leakage protection device, characterized in that, it includes: a housing and a functional circuit board disposed within the housing; a power input plug is provided on one side of the housing, and an output socket is provided on the other side; the functional circuit board includes an automatic live - neutral switching circuit, an intelligent ground wire module, and a leakage protection module; the automatic live - neutral switching circuit is connected to the power input plug, the intelligent ground wire module, and the leakage protection module; the output socket is connected to the intelligent ground wire module and the leakage protection module; the power input plug is provided with AC inputs IN1, IN2 for connecting an external power supply and a ground wire input G - in; the automatic live - neutral switching circuit is provided with a touch point T1. When the input terminals AC220A and AC220B of the automatic live - neutral switching circuit are respectively connected to the AC inputs of the power input plug, the user touches the touch point T1; If AC220A is connected to the live wire and AC220B is connected to the neutral wire, then current passes through a loop formed by the touch point T1, resistor R4, triode Q4, and AC220A in sequence. At this time, the triode Q4 conducts, the light - emitting diode of the optocoupler U1 lights up, the triode of the optocoupler U1 conducts, pulling down pin 1 of the controller MCU. At the same time, the triode Q2 cannot conduct, the optocoupler U2 does not conduct, and pin 8 of the controller MCU is at a high level; after the controller MCU detects that pin 1 is low and pin 8 is high, it determines that AC220A is connected to the live wire and AC220B is connected to the neutral wire. The controller MCU outputs a low level at pin 7, lighting up the line sequence indicator LEDL, and at the same time outputs a low level at pin 5, and the relay J1 is energized. At this time, the output port AC_OL of the output socket is the live wire, and the output port AC_ON is the neutral wire; If AC220B is the live wire and AC220A is the neutral wire, then current passes through a loop formed by the touch point T1, resistor R1, triode Q2, and AC220B in sequence. At this time, the triode Q2 conducts, the light - emitting diode of the optocoupler U2 lights up, the triode of the optocoupler U2 conducts, pulling down pin 8 of the controller MCU. At the same time, the triode Q4 cannot conduct, the optocoupler U1 does not conduct, and pin 1 of the controller MCU is at a high level; after the controller MCU detects that pin 8 is low and pin 1 is high, it determines that AC220B is connected to the live wire and AC220A is connected to the neutral wire. The controller MCU outputs a low level at pin 6, lighting up the line sequence indicator LEDN, and at the same time outputs a high level at pin 5, and the relay J1 is not energized. At this time, the output port AC_OL of the output socket is the live wire, and the output port AC_ON is the neutral wire; In the default case of the intelligent ground wire module, the relay J2 does not act, and the input ground wire GND of the power input plug and the AC_GND of the output socket are directly connected; When the controller MCU automatically switches the live - neutral sequence: If the input ground wire GND is connected to the ground wire input, the live wire output by the automatic zero-fire wire switching circuit forms a current loop in sequence through the light-emitting diode of the optocoupler U4, the resistor R9, and the input ground wire GND. At this time, the secondary triode of the optocoupler U4 conducts, pulling down the 3rd pin of the controller MCU. After detecting the low level of the 3rd pin, the controller MCU determines that there is a ground wire at the input ground wire GND end, and outputs a high level from the 4th pin of the controller MCU. The relay J2 remains inactive, and the input ground wire GND is directly connected to the AC_GND; If there is no ground wire at the input ground wire GND end, the live wire output by the automatic zero-fire wire switching circuit cannot form a current loop in sequence through the optocoupler U4, the resistor R9, and the input ground wire GND. The optocoupler U4 does not conduct, and the 3rd pin of the controller MCU is at a high level. After detecting the high level of the 3rd pin, the controller MCU determines that the input ground wire GND lacks the connection of the ground wire, and outputs a low level from the 4th pin of the controller MCU. The relay J2 is pulled in, and the AC_GND is connected to the neutral wire output by the automatic zero-fire wire switching circuit, using the neutral wire to replace the ground wire emergently.

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