Relay type ground fault protection device

Abstract

The present invention discloses a relay type ground fault protection device, which includes a switch module, a relay module, a leakage detection module, a self-test module and a drive module. The switch module is coupled between the input end and the output end of the trunk line to control the power connection between the input end and the output end; the relay module is coupled to the input end and the switch module to control the switch action of the switch module; the leakage detection module is coupled to the trunk line to detect whether there is a leakage fault signal at the output end of the trunk line; the self-test module is coupled to the trunk line and the leakage detection module to periodically generate a self-test pulse signal simulating a leakage current signal to detect whether the leakage detection module fails; the drive module is coupled to the leakage detection module, the self-test module and the relay module to drive the relay module based on the received leakage fault signal and / or the self-test fault signal related to the leakage detection module. The present invention has the advantages of high safety, simple structure, low cost, high detection sensitivity, etc.

Description

Technical Field

[0001] The invention relates to the electrical field, and in particular to a relay type ground fault protection device. Background Art

[0002] With the increasing popularity of household appliances, people pay more and more attention to the safety of household appliances, and the use of ground fault protection devices is becoming more and more widespread. However, the ground fault protection devices currently used still have certain defects. For example, when the detection circuit components in the ground fault protection device are damaged and lose their protection function, the coil of the relay therein is still in the energized state, so that the input end and the load are still in the power connection state, and the user cannot judge that the fault protection function of the ground fault protection device has failed, so there are safety hazards during the continued use of the load. For another example, the traditional ground fault protection device is implemented with multiple relay coils, which has the disadvantages of large product size, difficult manufacturing process, and high cost.

[0003] Therefore, there is an urgent need for a ground fault protection device that is easy to install and has obvious economic benefits. Summary of the invention

[0004] In view of the above problems, the present invention proposes a relay type ground fault protection device to improve product safety.

[0005] The present invention proposes a relay-type ground fault protection device, which includes: a switch module, a leakage detection module, a self-test module, a relay module and a drive module. The switch module is coupled between the input end and the output end of the trunk line, and is used to control the power connection between the input end and the output end; the relay module is coupled to the trunk line and the switch module, and is used to control the switch action of the switch module; the leakage detection module is coupled to the trunk line, and is used to detect whether there is a leakage fault signal at the output end of the trunk line; the self-test module is coupled to the trunk line and the leakage detection module, and is used to periodically generate a self-test pulse signal simulating a leakage fault signal to detect whether the leakage detection module fails; the drive module is coupled to the leakage detection module, the self-test module and the relay module, and is used to drive the relay module based on the received leakage fault signal and / or the self-test fault signal related to the leakage detection module. The relay module at least includes: a relay, an auxiliary reset component and an auxiliary switch; the relay is used to control the switching action of the switch module; the first end of the auxiliary reset component is coupled to the relay, the second end is coupled to the trunk line and the third end is coupled to the ground, and is used to control the switching state of the relay; the auxiliary switch is coupled to the relay to keep the relay working normally.

[0006] In one embodiment, when the relay module is powered on, the auxiliary reset component is driven to be turned on so that the relay controls the switch module and the auxiliary switch to be in a closed state; when the relay module works normally, the relay controls the switch module to remain in a closed state via the auxiliary switch.

[0007] In one embodiment, the driving module comprises:

[0008] a first driving control unit, a first end of which is coupled to the relay module, a second end of which is coupled to the leakage detection module and / or the self-test module, and a third end of which is coupled to ground, and is used to control the relay to be disconnected based on the leakage fault signal and / or the self-test fault signal, so that the switch module is in an off state; and

[0009] A second drive control unit, one end of which is coupled to the relay module and the other end of which is coupled to the leakage detection module and / or the self-test module, is used to control the auxiliary reset component to be disconnected based on the leakage fault signal and / or the self-test fault signal when the first drive control component is not working, so as to put the switch module in a disconnected state.

[0010] In one embodiment, the second driving control unit further comprises: a driving control component, a sound device or a light emitting device, a first end of the driving control component is coupled to the relay module via the sound device or the light emitting device, a second end of the driving control component is coupled to the leakage detection module and the self-test module, and a third end of the driving control component is coupled to the ground;

[0011] When the first drive control component does not work, the drive control component controls the relay to disconnect based on the leakage fault signal and / or the self-test fault signal to put the switch module in an off state and simultaneously enables the sound-emitting device or the light-emitting device to work.

[0012] In one embodiment, the relay-type ground fault protection device also includes: a fuse module, which is coupled between the input end and the relay module, and is used to increase the current passing through the fuse module while causing the first drive control unit and / or the second drive control unit to control the relay to disconnect based on the leakage fault signal and / or the self-test fault signal, and control the relay module to stop working by disconnecting the fuse module.

[0013] In one implementation, the second end of the auxiliary reset component is further coupled to a differential capacitor, and the differential capacitor is used to drive the relay to work when the relay module is powered on.

[0014] In one embodiment, the relay module further comprises: a normally open switch component, one end of which is coupled to the differential capacitor and the other end of which is coupled to the ground, and is configured to be triggered to close after the switch module is opened.

[0015] In one implementation, the fusing module is a fuse or any other fusible device.

[0016] In one implementation, the auxiliary resetting component, the first driving control unit, and the driving control component are one or more of field effect transistors, thyristors, triodes, or other switching elements.

[0017] In one embodiment, the second driving control unit further includes: the driving control component, the sound-generating device, and the light-emitting device connected in series.

[0018] Compared with the prior art, in order to increase the safety protection performance of the ground fault protection device, the present invention adds a relay module in the ground fault protection device, so that when the detection element of the disclosed relay-type ground fault protection device is damaged and loses its protection function, the relay coil can be powered off in time, thereby disconnecting the power connection between the input end and the load, thereby achieving safety protection of the user's life and property. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The embodiments are shown and explained with reference to the accompanying drawings. These drawings are used to explain the basic principles, and only the aspects necessary for understanding the basic principles are shown. These drawings are not to scale. In the drawings, the same reference numerals represent similar features.

[0020] Figure 1 A circuit structure schematic diagram of a ground fault protection device disclosed in the present invention is shown. DETAILED DESCRIPTION

[0021] In the following specific description of the preferred embodiments, reference will be made to the attached drawings which constitute a part of the present invention. The attached drawings show by way of example specific embodiments that can implement the present invention. The illustrative embodiments are not intended to be exhaustive of all embodiments according to the present invention. It will be appreciated that other embodiments may be utilized, and structural or logical modifications may also be made without departing from the scope of the present invention. Therefore, the following specific description is not restrictive, and the scope of the present invention is limited by the appended claims.

[0022] The technologies, methods and devices known to those skilled in the art may not be discussed in detail, but where appropriate, the technologies, methods and devices shall be considered as part of the specification. The connection lines between the units in the drawings are only for the convenience of explanation, which means that at least the units at both ends of the connection lines are in communication with each other, and are not intended to limit the inability of unconnected units to communicate with each other.

[0023] The embodiments of the present disclosure mainly focus on the following technical problems: the traditional ground fault protection device uses multiple groups of coils to achieve the effect of ground fault protection, which makes it have disadvantages such as large product size, difficult manufacturing process, and high cost; in addition, if the detection circuit components in the traditional ground fault protection device are damaged or lose their protection function, the coil is still in the energized state, and the user cannot determine that the ground fault protection device has failed.

[0024] In order to solve the above problems, this paper discloses a relay type ground fault protection device, which includes a switch module, a relay module, a leakage detection module, a self-test module and a drive module. The relay module is coupled to the input terminal, the switch module, and is coupled to the leakage detection module and the self-test module via the drive module, and is used to control the switching action of the switch module based on the received leakage fault signal and / or the self-test fault signal related to the leakage detection module.

[0025] like Figure 1 As shown, the relay type ground fault protection device disclosed in this embodiment includes: a switch module SW, a leakage detection module 1, a self-test module 2, a relay module 4, a drive module 3 and a fuse module 5. The switch module SW is coupled between the input terminal LINE and the output terminal LOAD of the trunk line, and is used to control the power connection between the input terminal LINE and the output terminal LOAD; the relay module 4 is coupled to the trunk line and the switch module SW, and is used to control the switching action of the switch module SW; the leakage detection module 1 is coupled to the trunk line, and is used to detect whether there is a leakage fault signal at the output terminal LOAD of the trunk line; the self-test module 2 is coupled to the trunk line and the leakage detection module 1, and is used to periodically generate a self-test pulse signal simulating a leakage current signal to detect whether the leakage detection module fails; the driving module 3 is coupled to the leakage detection module 1, the self-test module 2 and the relay module 4, and is used to drive the relay module based on the received leakage fault signal and / or the self-test fault signal related to the leakage detection module; the fuse module 5 is coupled between the input terminal LINE and the relay module 4, and is used to increase the current passing through the fuse module 5 while the driving module 3 controls the relay RELAY to be disconnected based on the leakage fault signal and / or the self-test fault signal, and control the relay of this embodiment to stop working by disconnecting the fuse module 5.

[0026] like Figure 1As shown, the relay module 4 includes: a current limiting component, a relay RELAY, an auxiliary reset component Q1, an auxiliary switch S1 and a normally open switch component RESET. Among them, the current limiting component is used to provide working current to the relay module 4; the first end of the relay RELAY is coupled to the current limiting component, which is used to control the switching action of the switch module SW; the first end of the auxiliary reset component Q1 is coupled to the second end of the relay RELAY, the second end is coupled to the trunk line and the third end is coupled to the ground, which is used to control the switching state of the relay RELAY; the auxiliary switch S1 is coupled to the relay RELAY, which is used to keep the relay RELAY working normally.

[0027] Specifically, Figure 1 As shown, the current limiting module at least includes: a diode D1, a resistor R4 and a diode D2 connected in series with the diode D1, resistors R6, R8 and a differential capacitor C8 connected in series with the diode D2 in sequence, and a resistor R22 connected in series with the resistor R4, etc. Among them, the differential capacitor C8 is coupled to the second end of the auxiliary reset component Q1, and is used to drive the relay RELAY to work when the relay module 4 is powered on.

[0028] In this embodiment, one end of the normally open switch component RESET in the relay module 4 is coupled to the differential capacitor C8 and the other end is coupled to the ground, so as to be triggered to close after the switch module SW is opened.

[0029] When the relay module 4 is powered on, the auxiliary reset component Q1 is turned on so that the relay RELAY control switch module SW and the auxiliary switch S1 are in a closed state.

[0030] When the relay module 4 works normally, the auxiliary reset component Q1 is disconnected, so that the relay RELAY keeps the switch module SW in a closed state via the auxiliary switch S1.

[0031] like Figure 1 As shown, the driving module 3 includes: a first driving control unit Q3 and a second driving control unit. The first end of the first driving control unit Q3 is coupled to the relay module 4, the second end is coupled to the leakage detection module 1 and the self-test module 2, and the third end is coupled to the ground, and is used to control the relay RELAY to be disconnected based on the leakage fault signal and / or the self-test fault signal, so that the switch module SW is in a disconnected state. One end of the second driving control unit is coupled to the relay module 4, and the other end is coupled to the leakage detection module 1 and the self-test module 2, and is used to control the auxiliary reset component Q1 to be disconnected based on the leakage fault signal and / or the self-test fault signal when the first driving control unit Q3 is not working, so that the switch module SW is in a disconnected state.

[0032] The second drive control unit further includes: a drive control component Q5, a sound-emitting device (not shown in the figure) or a light-emitting device LED, the first end of the drive control component Q5 is coupled to the relay module 4 via the sound-emitting device or the light-emitting device LED, the second end of the drive control component Q5 is coupled to the leakage detection module 1 and the self-test module 2, and the third end of the drive control component Q5 is coupled to the ground.

[0033] When the first drive control unit Q3 is not working, the drive control component Q5 controls the relay RELAY to disconnect based on the leakage fault signal and / or the self-test fault signal to put the switch module SW in the disconnected state, and at the same time makes the sound device or the light-emitting device LED work to remind the user that the relay-type ground fault protection device has a fault.

[0034] like Figure 1 As shown, the leakage detection module 1 includes a leakage detection ring CT1 passing through the phase line L and the neutral line N, a neutral line detection ring CT2, and a leakage detection unit coupled to the leakage detection ring CT1 (which includes a leakage detection chip U1 and related coupled electronic components (for example, capacitor C2, etc.)). When there is a current imbalance between the phase line L and the neutral line N passing through the leakage detection ring CT1, that is, when there is a leakage current signal, a corresponding voltage signal will be generated on the leakage detection ring CT1, and the leakage detection chip U1 will control the first drive control unit Q3 and / or the second drive control component to turn on by detecting that the leakage current signal on the leakage detection ring CT1 exceeds a preset value, thereby disconnecting the relay RELAY, and then disconnecting the switch module SW.

[0035] In this embodiment, the self-test module 2 is used to perform periodic functional checks on the leakage detection module 1. The self-test module 1 includes a power supply circuit, a periodic timing circuit, and a self-test pulse signal circuit that simulates a leakage current signal. Figure 1 The power supply circuit includes a resistor R10 and a voltage regulator ZD1; the periodic timing circuit includes a resistor R12 and a timing element (e.g., a capacitor C11) connected in series to generate the interval of the self-test pulse signal; the self-test pulse signal circuit includes a transistor (thyristor Q2), a comparator U2, a diode D7, a capacitor C14, a resistor R18, and electronic components such as resistors R7 and R16 respectively coupled to the transistor Q2. After the ground fault protection device works, the self-test module 2 periodically applies a simulated leakage current signal reaching a predetermined value to the leakage detection loop CT1.

[0036] The working principle of this embodiment is as follows:

[0037] First, when the relay module 4 is coupled to the trunk line, the current passes through the fuse module 5, the diode D1, the diode D2, the resistor R6, and the resistor R8, and charges the differential capacitor C8, which instantly turns on the auxiliary reset component Q1, so that the phase line L, the relay RELAY, the auxiliary reset component Q1 and the neutral line N form a current loop, and then the relay RELAY drives the switch module SW and the auxiliary switch S1 to close. Then the auxiliary reset component Q1 is disconnected, and the relay RELAY remains in the working state based on the closed auxiliary switch S1.

[0038] At the same time, the leakage detection module 1 obtains the working power through the fuse module 5 , the diode D1 , the diode D2 , and the resistor R6 , and the diode D4 of the self-test module 2 is turned on to provide the working power to the self-test module 2 .

[0039] When the leakage detection loop CT1 detects a leakage current signal (i.e., a ground fault signal), a corresponding voltage signal will be generated on the leakage detection loop CT1. The leakage detection chip U1 detects that the leakage current signal on the leakage detection loop CT1 exceeds a preset value, thereby triggering the first drive control unit Q3 in the drive module 3 to turn on through the diode D5 and the resistor R14, thereby pulling down the Figure 1 The potential at point A causes the relay RELAY to lose power, and controls the switch module SW and the auxiliary switch S1 to be disconnected at the same time, thereby protecting the safety of people or property.

[0040] When the function of the leakage detection module 1 is lost (for example, the leakage detection loop CT1 is short-circuited or the leakage detection chip U1 is damaged, etc.), the self-test signal periodically sent by the transistor Q2 in the self-test module 2 cannot be fed back to the self-test module 2, and the resistor R18 will charge the capacitor C14, so that the diode D7 is turned on (that is, a self-test fault signal is generated), which further triggers the first drive control unit Q3 to turn on, thereby pulling down Figure 1 The potential at point A causes the relay RELAY to lose power, and controls the switch module SW and the auxiliary switch S1 to be disconnected at the same time, thereby protecting the safety of people or property.

[0041] In addition, when the first drive control unit Q3 in the drive module 3 is open circuit (for example, damaged), when the drive module 3 receives a leakage fault signal and / or a self-test fault signal from the self-test module 2, the drive control component Q5 in the second drive control component is turned on, so that the phase line L, the fuse module 5, the diode D1, the resistors R4 and R15, the light-emitting device LED, the drive control component Q5 and the neutral line N form a current loop, and then the relay RELAY loses power, and the switch module SW is controlled to be disconnected, thereby protecting personal or property safety; at the same time, the operation of the light-emitting device LED can remind the user that the ground fault protection device has a fault.

[0042] Alternatively, the light emitting device LED may be replaced by a sound emitting device to alert the user that the ground fault protection device is faulty.

[0043] Optionally, the second drive control component may include a sound device, a light emitting device LED and a drive control component Q5 at the same time, so as to use auditory effects and visual effects at the same time to remind the user that the ground fault protection device is faulty.

[0044] In this embodiment, the disclosed auxiliary reset component Q1, the first drive control unit Q3, the drive control component Q5 and other components may be semiconductor elements such as MOS tubes, thyristors, triodes and the like.

[0045] The relay-type ground fault protection device disclosed herein can control the relay module to disconnect the switch module when a ground fault and / or a leakage detection module fault is detected. That is, the present invention can timely detect the potential safety hazards in the use of electrical appliances, and take corresponding measures to eliminate the potential safety hazards, and can also remind the user that the fault protection device has potential safety hazards, thereby ultimately improving the safety performance of electrical products.

[0046] Therefore, although the present invention is described with reference to specific examples, wherein these specific examples are intended to be illustrative only and not limiting of the present invention, it is obvious to those skilled in the art that the disclosed embodiments may be changed, added or deleted without departing from the spirit and scope of the present invention.

Claims

1. A relay type ground fault protection device, characterized in that: include: A switch module, coupled between an input end and an output end of the trunk line, for controlling a power connection between the input end and the output end; A relay module, coupled to the trunk line and the switch module, for controlling the switching action of the switch module, wherein the relay module at least comprises: A relay is used to control the switching action of the switch module. an auxiliary reset component, a first end of which is coupled to the relay, a second end of which is coupled to the trunk line and a third end of which is coupled to the ground, for controlling the pull-in state of the relay, and an auxiliary switch, coupled to the relay, for maintaining the normal operation of the relay; A leakage detection module, coupled to the trunk line, for detecting whether there is a leakage fault signal at the output end of the trunk line; a self-check module coupled to the trunk line and the leakage detection module, and configured to periodically generate a self-check pulse signal simulating a leakage current signal to detect whether the leakage detection module fails; and a driving module coupled to the leakage detection module, the self-test module and the relay module, and configured to drive the relay module based on the received leakage fault signal and / or the self-test fault signal related to the leakage detection module, Wherein, when the relay module is powered on, the auxiliary reset component is driven to be turned on so that the relay controls the switch module and the auxiliary switch to be in a closed state; when the relay module works normally, the relay controls the switch module to remain in a closed state via the auxiliary switch.

2. The relay type ground fault protection device according to claim 1, characterized in that: The driving module comprises: a first driving control unit, a first end of which is coupled to the relay module, a second end of which is coupled to the leakage detection module and / or the self-test module, and a third end of which is coupled to ground, and is used to control the relay to be disconnected based on the leakage fault signal and / or the self-test fault signal, so that the switch module is in an off state; and A second drive control unit, one end of which is coupled to the relay module, and the other end of which is coupled to the leakage detection module and / or the self-test module, is used to control the auxiliary reset component to be disconnected based on the leakage fault signal and / or the self-test fault signal when the first drive control unit is not working, so as to put the switch module in a disconnected state.

3. The relay type ground fault protection device according to claim 2, characterized in that: The second driving control unit further comprises: a driving control component, a sound device or a light emitting device, a first end of the driving control component is coupled to the relay module via the sound device or the light emitting device, a second end of the driving control component is coupled to the leakage detection module and / or the self-test module, and a third end of the driving control component is coupled to the ground; When the first drive control unit does not work, the drive control component controls the relay to disconnect based on the leakage fault signal and / or the self-test fault signal to put the switch module in an off state and simultaneously enables the sound-emitting device or the light-emitting device to work.

4. The relay type ground fault protection device according to claim 2, characterized in that: Also includes: A fuse module is coupled between the input end and the relay module, and is used to increase the current passing through the fuse module while causing the first drive control unit and / or the second drive control unit to control the relay to disconnect based on the leakage fault signal and / or the self-test fault signal, and control the relay module to stop working by disconnecting the fuse module.

5. The relay type ground fault protection device according to claim 1, characterized in that: The second end of the auxiliary reset component is further coupled to a differential capacitor, and the differential capacitor is used to drive the relay to work when the relay module is powered on.

6. The relay type ground fault protection device according to claim 5, characterized in that: The relay module also includes: A normally open switch component has one end coupled to the differential capacitor and the other end coupled to the ground, and is used to be triggered to close after the switch module is opened.

7. The relay type ground fault protection device according to claim 4, characterized in that: The fusing module is a fuse.

8. The relay type ground fault protection device according to claim 3, characterized in that: The auxiliary resetting component, the first driving control unit, and the driving control component are one or more of field effect transistors, thyristors, or triodes.

9. The relay type ground fault protection device according to claim 3, characterized in that: The second driving control unit further includes: the driving control component, the sound generating device and the light emitting device connected in series.

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