Detection protection device for power line, electric connection device and electric appliance

Abstract

The application discloses a detection protection device of a power line, an electric connection device and an electric equipment. The power line comprises a first current-carrying wire, a second current-carrying wire, a first shielding conductor and a second shielding conductor. The detection protection device comprises a direct-current power module, a self-checking path module and a response processing module. The direct-current power module is electrically connected to one end of the first shielding conductor and one end of the second shielding conductor. The other end of the first shielding conductor and the other end of the second shielding conductor are electrically connected to the ground end through the self-checking path module. The response processing module disconnects the power connection between the input end and the output end of the power line under the condition that the first shielding conductor is open, the second shielding conductor is open, or the first shielding conductor and / or the second shielding conductor detects a leakage signal. The application can effectively and reliably realize the leakage detection of the power line and the open circuit detection of the shielding conductor of the power line.

Description

Technical Field

[0001] This invention relates to the field of electrical technology, and in particular to a power cord detection and protection device, an electrical connection device, and an electrical appliance. Background Technology

[0002] A leakage circuit breaker (LCDI) is a power connection device for electrical appliances. It detects leakage current in the power supply line via a leakage current detection lead and disconnects the power supply to the appliance when a certain leakage current is detected, ensuring safe operation. In recent years, LCDIs have not only needed to detect leakage current in the power supply line via the leakage current detection lead, but also have higher safety detection requirements, such as detecting whether the leakage current detection lead is open-circuited.

[0003] How to effectively and reliably detect leakage current in power cords and detect open circuits in the shielding conductors of power cords has become a problem that current power connection devices need to solve. Summary of the Invention

[0004] The purpose of this invention is to at least solve one of the technical problems existing in the prior art, and to provide a power cord detection and protection device, an electrical connection device and an electrical device, which can effectively and reliably realize leakage detection of power cords and open circuit detection of the shielding conductor of power cords.

[0005] In a first aspect, embodiments of the present invention provide a power line detection and protection device, wherein the power line includes a first current-carrying wire, a second current-carrying wire, a first shielding conductor covering the first current-carrying wire, and a second shielding conductor covering the second current-carrying wire; the detection and protection device includes a DC power supply module, a self-test path module, and a response processing module, wherein: The DC power module is electrically connected to one end of the first shielding conductor and / or one end of the second shielding conductor, and is used to provide DC detection current to the first shielding conductor and / or the second shielding conductor. The other end of the first shielding conductor and the other end of the second shielding conductor are electrically connected to the ground terminal through the self-test path module; The response processing module is electrically connected to the self-test path module and is used to disconnect the power connection between the input and output terminals of the power line when the first shielding conductor is open, the second shielding conductor is open, the first shielding conductor detects a leakage signal and / or the second shielding conductor detects a leakage signal.

[0006] The power cord detection and protection device provided according to the embodiments of the present invention has at least the following beneficial effects: the first shielding conductor covers the first current-carrying wire, thereby enabling the collection of leakage current signals of the first current-carrying wire; the second shielding conductor covers the second current-carrying wire, thereby enabling the collection of leakage current signals of the second current-carrying wire; based on this, under the action of the DC detection current provided by the DC power supply module, the self-test path module, together with the first and second shielding conductors, forms a self-test path; in the event of leakage or open circuit, the power connection between the input and output terminals of the power cord is disconnected by the response processing module, ensuring the power supply safety of the power cord; the power cord detection and protection device can effectively and reliably realize leakage detection of the power cord and open circuit detection of the shielding conductor of the power cord.

[0007] According to some embodiments of the detection and protection device provided by the present invention, the DC power supply module is provided with a DC power supply terminal; The self-test path module includes a first self-test unit, a second self-test unit, and a third self-test unit; the first self-test unit is electrically connected between the DC power supply terminal and the ground terminal, and is provided with a first detection terminal; the second self-test unit is electrically connected to the first self-test unit and is provided with a second detection terminal, the second detection terminal being electrically connected to one end of the first shielding conductor and one end of the second shielding conductor respectively; the third self-test unit is electrically connected to the other end of the first shielding conductor, the other end of the second shielding conductor, and the ground terminal respectively. The response processing module is electrically connected to the first detection terminal, the second detection terminal, the first current-carrying line, and the second current-carrying line, respectively.

[0008] In this embodiment, the first self-test unit, the second self-test unit, and the third self-test unit in the self-test path module, together with the first shielding conductor and the second shielding conductor, form a self-test path. A first detection end and a second detection end are provided. When there is no leakage or open circuit, the potentials of the first and second detection ends remain constant, and the response processing module will not be triggered. When leakage or open circuit occurs, the potentials of the first and second detection ends change, triggering the response processing module to disconnect the power connection between the input and output ends of the power cord, ensuring the power supply safety of the power cord. This power cord detection and protection device can effectively and reliably detect leakage in the power cord and detect open circuits in the shielding conductor.

[0009] The detection and protection device provided according to some embodiments of the present invention further includes a test module, the test module including a test switch and a first resistor, one end of the test switch being connected to one end of the first resistor; The other end of the test switch is connected to one of the first current-carrying line, the second current-carrying line, and the DC power supply terminal. The other end of the first resistor is connected to one of the first detection terminal, the second detection terminal, the first shielding conductor, and the second shielding conductor.

[0010] According to some embodiments of the present invention, the detection and protection device includes a first self-test unit comprising a second resistor, a third resistor, and a first diode connected in sequence; the second resistor is connected to the DC power supply terminal, and the cathode of the first diode is connected to the ground terminal; the connection point of the second resistor and the third resistor serves as the first detection terminal.

[0011] According to some embodiments of the present invention, the detection and protection device includes a second self-test unit comprising a fourth resistor and a fifth resistor connected in sequence. The fourth resistor is connected to the DC power supply terminal, and the fifth resistor is connected to the anode of the first diode. The connection point between the fourth resistor and the fifth resistor serves as the second detection terminal.

[0012] According to some embodiments of the present invention, the detection and protection device includes a third self-test unit comprising a sixth resistor and a seventh resistor; the two ends of the sixth resistor are respectively connected to the other end of the first shielding conductor and the ground terminal, and the two ends of the seventh resistor are respectively connected to the other end of the second shielding conductor and the ground terminal.

[0013] According to some embodiments of the present invention, the detection and protection device further includes a second diode and a third diode, a sixth resistor connected to the anode of the second diode, a seventh resistor connected to the anode of the third diode, and the cathodes of the second diode and the third diode connected to the ground terminal.

[0014] According to some embodiments of the present invention, the detection and protection device is provided in which the DC power supply module adopts an isolated power supply, and the DC power supply terminal is electrically connected to the self-test path module, the first shielding conductor and the second shielding conductor to form a low-voltage DC self-test path.

[0015] According to some embodiments of the present invention, an isolation field is formed inside the isolation power supply to isolate the input current from the output current.

[0016] According to some embodiments of the present invention, the detection and protection device includes a response processing module comprising a fault response module and a triggering module. The fault response module is connected to the first detection terminal, the second detection terminal and the triggering module respectively, and the triggering module is connected to the fault response module, the first current-carrying line and the second current-carrying line respectively. The fault response module is used to acquire the open circuit signal generated when the first shielding conductor and / or the second shielding conductor is open, and to acquire the leakage current signal detected by the first shielding conductor and / or the second shielding conductor, and to output a trip trigger signal in response to the open circuit signal or the leakage current signal. The trigger module is configured to disconnect the power connection between the input and output terminals of the power line via a switch module in response to receiving the trip trigger signal.

[0017] According to some embodiments of the present invention, the fault response module of the detection and protection device includes a first transistor, a second transistor, an eighth resistor, a ninth resistor, and a tenth resistor. The emitter of the first transistor is connected to one end of the eighth resistor, the base of the second transistor is connected to one end of the ninth resistor, and the emitter of the second transistor is connected to one end of the tenth resistor. The base of the first transistor and the other end of the tenth resistor are both connected to the first detection terminal; the other ends of the eighth resistor and the ninth resistor are both connected to the second detection terminal. The collectors of the first transistor and the second transistor are connected together and connected to the trigger module to output the trip trigger signal to the trigger module.

[0018] According to some embodiments of the present invention, when the first current-carrying line leaks current to the first shielding conductor, a leakage current signal is sent to the first transistor through the second detection terminal, causing the first transistor to conduct so as to output the trip trigger signal to the trigger module.

[0019] According to some embodiments of the present invention, when the second current-carrying line leaks current to the second shielding conductor, a leakage current signal is sent to the second transistor through the first detection terminal, causing the second transistor to conduct so as to output the trip trigger signal to the trigger module.

[0020] According to some embodiments of the present invention, when the first shielding conductor and / or the second shielding conductor is open-circuited, an open-circuit signal is sent to the first transistor through the second detection terminal, causing the first transistor to conduct so as to output the trip trigger signal to the trigger module.

[0021] According to some embodiments of the present invention, the first transistor and the second transistor are PNP transistors.

[0022] In a second aspect, embodiments of the present invention provide an electrical connection device, including the detection and protection device, housing, and power cord as described in the first aspect embodiment above, wherein the power cord is connected to the housing, and the DC power module, the first self-test unit, the second self-test unit, and the response processing module are disposed in the housing.

[0023] Thirdly, embodiments of the present invention provide an electrical device, including a load device and an electrical connection device as described in the second aspect of the embodiments above, wherein the output end of the power line is connected to the load device.

[0024] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the description, claims, and drawings. Attached Figure Description

[0025] The accompanying drawings are provided to further understand the technical solutions of the present invention and constitute a part of the specification. They are used together with the embodiments of the present invention to explain the technical solutions of the present invention, and do not constitute a limitation on the technical solutions of the present invention.

[0026] The present invention will be further described below with reference to the accompanying drawings and embodiments; Figure 1 This is a circuit diagram of the detection and protection device provided in an embodiment of the present invention; Figure 2 This is the equivalent circuit of the self-test path formed in the embodiments of the present invention; Figure 3 This is a schematic diagram of the current signal flow direction under the condition of leakage in the first current-carrying line provided in the embodiment of the present invention; Figure 4 This is a schematic diagram of the current signal flow direction under the condition of leakage in the second current-carrying line provided in the embodiment of the present invention; Figure 5 This is a schematic diagram of the current signal flow when the first shielding conductor is open-circuited, provided in an embodiment of the present invention. Figure 6 This is a schematic diagram of the current signal flow when the second shielding conductor is open-circuited, provided in an embodiment of the present invention. Figure 7 This is a schematic diagram of the current signal flow when the test switch is pressed, provided in an embodiment of the present invention. Figure 8 This is a schematic diagram of the structure of the electrical connection device provided in an embodiment of the present invention. Detailed Implementation

[0027] This section will describe in detail specific embodiments of the present invention. Preferred embodiments of the present invention are shown in the accompanying drawings. The purpose of the drawings is to supplement the textual description with graphics, so that people can intuitively and vividly understand each technical feature and overall technical solution of the present invention, but they should not be construed as limiting the scope of protection of the present invention.

[0028] In the description of the embodiments of the present invention, "several" means one or more, "multiple" means two or more, "greater than," "less than," "exceeding," etc. are understood to exclude the number itself, while "above," "below," "within," etc. are understood to include the number itself. "At least one" refers to one or more, and "at least one of the following" and similar expressions refer to any combination of these items, including any combination of single or multiple items. If "first," "second," etc., are used in the description, they are only for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance or implicitly indicating the number of indicated technical features or the order of the indicated technical features.

[0029] It should be noted that the terms "setting," "installing," and "connecting" in the embodiments of this invention should be interpreted broadly. Those skilled in the art can reasonably determine the specific meaning of the above terms in the embodiments of this invention in conjunction with the specific content of the technical solution. For example, the term "connection" can be a mechanical connection, an electrical connection, or a connection that allows for mutual communication; it can be a direct connection or an indirect connection through an intermediate medium.

[0030] It should be noted that the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0031] A leakage circuit breaker (LCDI) is a power connection device for electrical appliances. It detects leakage current in power lines using a leakage current detection lead and disconnects the power supply to the appliance when a certain leakage current is detected, ensuring safe operation. In recent years, LCDIs have faced higher safety requirements beyond simply detecting leakage current in power lines, such as detecting open circuits in the leakage current detection lead. How to effectively and reliably detect leakage current in power lines and detect open circuits in the shielding conductors of power lines has become a problem that current power connection devices need to solve.

[0032] Based on this, embodiments of the present invention provide a power cord detection and protection device, an electrical connection device, and an electrical appliance, which can effectively and reliably realize leakage current detection of power cords and open circuit detection of the shielding conductor of power cords.

[0033] The embodiments of the present invention will be further described below with reference to the accompanying drawings.

[0034] Figure 1 This is a circuit diagram of the detection and protection device provided in an embodiment of the present invention. (Refer to...) Figure 1 A first aspect of the present invention provides a power line detection and protection device, wherein the power line includes a first current-carrying line 110, a second current-carrying line 120, a first shielding conductor 130 covering the first current-carrying line 110, and a second shielding conductor 140 covering the second current-carrying line 120.

[0035] It is understandable that when a power supply line supplies power to electrical equipment using two-phase AC power, it can be one of the following two scenarios: the first current-carrying wire 110 is the live wire L, and the second current-carrying wire 120 is the neutral wire N; or the first current-carrying wire 110 is the neutral wire N, and the second current-carrying wire 120 is the live wire L. When a power supply line supplies power to electrical equipment using three-phase AC power, it can be one of the following three scenarios: the first current-carrying wire 110 is the live wire L1, and the second current-carrying wire 120 is the neutral wire N; the first current-carrying wire 110 is the neutral wire N, and the second current-carrying wire 120 is the live wire L1; or the first current-carrying wire 110 is the live wire L1, and the second current-carrying wire 120 is the live wire L2. Below, we will use... Figure 1 The following example illustrates the situation where the first current-carrying line 110 is the live wire L and the second current-carrying line 120 is the neutral wire N. The other cases can be understood in the same way.

[0036] Continue to refer to Figure 1 The first shielding conductor 130 is used to collect the leakage current signal of the first current-carrying line 110, and the second shielding conductor 140 is used to collect the leakage current signal of the second current-carrying line 120. The first shielding conductor 130 includes a first end a near the input end of the power line and a second end b near the output end of the power line. The second shielding conductor 140 includes a fourth end d near the input end and a fifth end e near the output end.

[0037] The detection and protection device includes a DC power supply module 100, a self-test path module, and a response processing module, wherein: The DC power module 100 is used to provide a DC detection current to the first shielding conductor 130 and / or the second shielding conductor 140, for example by outputting a 12V DC voltage to provide the DC detection current; The DC power module 100 is electrically connected to one end of the first shielding conductor 130 and one end of the second shielding conductor 140 through the self-test path module. The other end of the first shielding conductor 130 and the other end of the second shielding conductor 140 are electrically connected to the ground terminal through the self-test path module. The response processing module is electrically connected to the self-test path module, and is used to disconnect the power connection between the input and output terminals of the power cord in the event that the first shielding conductor 130 is open, the second shielding conductor 140 is open, the first shielding conductor 130 detects a leakage current signal and / or the second shielding conductor 140 detects a leakage current signal.

[0038] According to the power cord detection and protection device provided in the embodiment of the present invention, the first shielding conductor 130 covers the first current-carrying wire 110 to collect the leakage current signal of the first current-carrying wire 110, and the second shielding conductor 140 covers the second current-carrying wire 120 to collect the leakage current signal of the second current-carrying wire 120. On this basis, under the action of the DC detection current provided by the DC power module 100, the self-test path module, together with the first shielding conductor 130 and the second shielding conductor 140, forms a self-test path. In the event of leakage or open circuit, the power connection between the input and output terminals of the power cord is disconnected by the response processing module to ensure the power supply safety of the power cord. The power cord detection and protection device can effectively and reliably realize the leakage detection of the power cord and the open circuit detection of the shielding conductor of the power cord.

[0039] Reference Figure 1 In some embodiments of the detection and protection device provided by the present invention, the DC power supply module 100 is provided with a DC power supply terminal VDD; the self-test path module includes a first self-test unit 210, a second self-test unit 220 and a third self-test unit 230; the first self-test unit 210 is electrically connected between the DC power supply terminal VDD and the ground terminal, and is provided with a first detection terminal X; the second self-test unit 220 is electrically connected to the first self-test unit 210 and is provided with a second detection terminal Y, the second detection terminal Y being electrically connected to one end of the first shielding conductor 130 and the second shielding conductor 140. Specifically, one end of 40, the second detection end Y, is connected to the first end a of the first shielded conductor 130 near the input end of the power line and the fourth end d of the second shielded conductor 140 near the input end of the power line; the third self-test unit 230 is electrically connected to the other end of the first shielded conductor 130, the other end of the second shielded conductor 140, and the ground end, respectively. Specifically, the third self-test unit 230 is connected to the second end b of the first shielded conductor 130 near the output end of the power line and the fifth end e of the second shielded conductor 140 near the output end of the power line. The response processing module is electrically connected to the first detection terminal X, the second detection terminal Y, the first current-carrying line 110, and the second current-carrying line 120, respectively.

[0040] Understandably, the detection and protection device also includes a switch module 500 for controlling the power connection between the input and output terminals of the power cord. (See reference...) Figure 1 As shown, the switch module 500 is provided with switch terminals on the first current-carrying line 110 and the second current-carrying line 120. When the switch terminals of the switch module 500 are closed, the power connection between the input end and the output end of the power line is made on; when the switch terminals of the switch module 500 are open, the power connection between the input end and the output end of the power line is disconnected.

[0041] In this embodiment, the first self-test unit 210, the second self-test unit 220, and the third self-test unit 230 in the self-test path module, together with the first shielding conductor 130 and the second shielding conductor 140, form a self-test path and are provided with a first detection terminal X and a second detection terminal Y. When there is no leakage or open circuit, the potentials of the first detection terminal X and the second detection terminal Y are constant and will not trigger the response processing module. When leakage and / or open circuit occur, the potentials of the first detection terminal X and the second detection terminal Y change, which will trigger the response processing module to disconnect the power connection between the input and output terminals of the power cord, thus ensuring the power supply safety of the power cord. This power cord detection and protection device can effectively and reliably realize leakage detection of the power cord and open circuit detection of the shielding conductor of the power cord.

[0042] Reference Figure 1 In some embodiments of the present invention, the detection and protection device includes a first self-test unit 210 comprising a second resistor R2, a third resistor R3 and a first diode D1 connected in sequence; the second resistor R2 is connected to the DC power supply terminal VDD, and the cathode of the first diode D1 is connected to the ground terminal; the connection point of the second resistor R2 and the third resistor R3 serves as the first detection terminal X.

[0043] In this embodiment, the DC detection voltage provided by the DC power supply terminal VDD is divided by the second resistor R2 and the third resistor R3 in the first self-test unit 210 to determine the potential of the first detection terminal X; and the first diode D1 is set to limit the current flow direction to DC power supply terminal VDD - second resistor R2 - third resistor R3 - first diode D1 - ground terminal.

[0044] Reference Figure 1 In some embodiments of the present invention, the detection and protection device includes a second self-test unit 220 comprising a fourth resistor R4 and a fifth resistor R5 connected in sequence. The fourth resistor R4 is connected to the DC power supply terminal VDD, and the fifth resistor R5 is connected to the anode of the first diode D1. The connection point of the fourth resistor R4 and the fifth resistor R5 serves as the second detection terminal Y.

[0045] In this embodiment, the DC detection voltage provided by the DC power supply terminal VDD is divided by the fourth resistor R4 and the fifth resistor R5 in the second self-test unit 220 to determine the initial potential of the second detection terminal Y. Furthermore, the second detection terminal Y is connected to one end of the first shielding conductor 130 and one end of the second shielding conductor 140. The first shielding conductor 130 and the second shielding conductor 140, together with the third self-test unit 230, can adjust the potential of the second detection terminal Y to determine the final potential of the second detection terminal Y.

[0046] Reference Figure 1In some embodiments of the detection and protection device provided by the present invention, the third self-test unit 230 includes a sixth resistor R6, a seventh resistor R7, a second diode D2, and a third diode D3; the two ends of the sixth resistor R6 are respectively connected to the other end of the first shielding conductor 130 and the anode of the second diode D2, and the two ends of the seventh resistor R7 are respectively connected to the other end of the second shielding conductor 140 and the anode of the third diode D3; the cathodes of the second diode D2 and the third diode D3 are connected to ground. Specifically, the equivalent circuit of the self-test path formed by the first self-test unit 210, the second self-test unit 220, and the third self-test unit 230 in the self-test path module in conjunction with the first shielding conductor 130 and the second shielding conductor 140 is as follows: Figure 2 As shown.

[0047] In this embodiment, the sixth resistor R6 in the third self-test unit 230 is connected in series with the first shielding conductor 130 to form a detection path corresponding to the first shielding conductor 130, and the seventh resistor R7 in the third self-test unit 230 is connected in series with the second shielding conductor 140 to form a detection path corresponding to the second shielding conductor 140. These two detection paths are connected in parallel between the second detection terminal Y and the ground terminal, which can adjust the potential of the second detection terminal Y, thereby determining the final potential of the second detection terminal Y. Furthermore, leakage signals are detected in the first shielding conductor 130, the second shielding conductor 140, and the first shielding conductor... If 130 or the second shielding conductor 140 is open-circuited, it will affect the potential of the first detection terminal X or the second detection terminal Y, thereby triggering the response processing module to disconnect the power connection between the input and output terminals of the power line, ensuring the power supply safety of the power line. In addition, by setting the second diode D2, the current flow through the sixth resistor R6 is limited to the first shielding conductor 130 - the sixth resistor R6 - the second diode D2 - ground. The third diode D3 is set to limit the current flow through the seventh resistor R7 to the second shielding conductor 140 - the seventh resistor R7 - the third diode D3 - ground.

[0048] Reference Figure 1 In some embodiments of the present invention, the detection and protection device also includes a test module 300. The test module 300 includes a test switch TEST and a first resistor R1. One end of the test switch TEST is connected to one end of the first resistor R1. The other end of the test switch TEST is connected to the first current-carrying line 110. The other end of the first resistor R1 is connected to the second detection terminal Y.

[0049] In this embodiment, when the test switch TEST in the test module 300 is pressed, it is equivalent to connecting the first current-carrying line 110 to the second detection terminal Y, that is, simulating the leakage current signal of the first current-carrying line 110 to be transmitted to the second detection terminal Y, so as to test whether the leakage current detection function of the protection device is intact.

[0050] Understandably, the other end of the test switch TEST can also be connected to the second current-carrying line 120 or the DC power supply terminal VDD; the other end of the first resistor R1 can be connected to the first detection terminal X, the first shielding conductor 130, or the second shielding conductor 140. All of the above settings of the test module 300 can cause a change in the potential of the first detection terminal X or the second detection terminal Y, thereby triggering the response processing module to test whether the leakage current detection function of the protection device is intact.

[0051] In some embodiments of the present invention, the detection and protection device provides a DC power module 100 that uses an isolated power supply. The DC power supply terminal VDD is electrically connected to the self-test path module, the first shielding conductor 130, and the second shielding conductor 140 to form a low-voltage DC self-test path. The low-voltage DC self-test path is used to detect leakage current in the power line and open circuit in the shielding conductor of the power line.

[0052] In this embodiment, the input side of the isolated power supply used in the DC power module 100 can be connected to an independent battery module, a solar module, or mains power, as long as it can provide power.

[0053] In some embodiments of the present invention, an isolation field is formed inside the isolation power supply to isolate the input current from the output current.

[0054] In this embodiment, the isolation power supply, through the isolation field formed inside, can enhance the anti-interference capability and stability of the detection and protection device, playing a key role in achieving safety protection.

[0055] In some embodiments of the present invention, the input terminal of the DC power module 100 is connected to the first current-carrying line 110 and the second current-carrying line 120, and the second current-carrying line 120 is connected to the ground terminal.

[0056] In this embodiment, by setting up the isolated DC power supply module 100, the DC power supply terminal VDD is isolated from the first current-carrying line 110, and the DC detection current obtained by the self-test path formed by the self-test path module, the first shielding conductor 130, and the second shielding conductor 140 is more stable and less susceptible to interference.

[0057] Reference Figure 1 In some embodiments of the present invention, the detection and protection device includes a fault response module 410 and a trigger module 420. The fault response module 410 is connected to the first detection terminal X, the second detection terminal Y and the trigger module 420 respectively. The trigger module 420 is connected to the fault response module 410, the first current-carrying line 110 and the second current-carrying line 120 respectively. The fault response module 410 is used to acquire the open circuit signal generated when the first shielding conductor 130 and / or the second shielding conductor 140 is open, and to acquire the leakage current signal detected by the first shielding conductor 130 and / or the second shielding conductor 140, and to output a trip trigger signal in response to the open circuit signal or the leakage current signal. Trigger module 420 is configured to disconnect the power connection between the input and output terminals of the power line via switch module 500 in response to receiving a trip trigger signal.

[0058] Continue to refer to Figure 1 In some embodiments of the present invention, the fault response module 410 includes a first transistor Q1, a second transistor Q2, an eighth resistor R8, a ninth resistor R9, and a tenth resistor R10. The emitter of the first transistor Q1 is connected to one end of the eighth resistor R8, the base of the second transistor Q2 is connected to one end of the ninth resistor R9, and the emitter of the second transistor Q2 is connected to one end of the tenth resistor R10. The base of the first transistor Q1 and the other end of the tenth resistor R10 are both connected to the first detection terminal X; the other ends of the eighth resistor R8 and the ninth resistor R9 are both connected to the second detection terminal Y. The collector of the first transistor Q1 and the collector of the second transistor Q2 are connected together and connected to the trigger module 420 to output a trip trigger signal to the trigger module 420.

[0059] In this embodiment, when the voltage received at the emitter of the first transistor Q1 is greater than the voltage received at the base of the first transistor Q1, the emitter junction of the first transistor Q1 is forward-biased and thus conducts, thereby outputting a trip trigger signal to the trigger module 420 through the collector of the first transistor Q1; similarly, when the voltage received at the emitter of the second transistor Q2 is greater than the voltage received at the base of the second transistor Q2, the emitter junction of the second transistor Q2 is forward-biased and thus conducts, thereby outputting a trip trigger signal to the trigger module 420 through the collector of the second transistor Q2.

[0060] Reference Figure 1In some embodiments of the present invention, the detection and protection device includes a trigger module 420 comprising a thyristor Q3, a thyristor drive module 421, and a trip coil Lx for generating electromagnetic force to drive the switch module 500 to disconnect the power connection; the thyristor drive module 421 includes a twelfth resistor R12, a thirteenth resistor R13, and a first capacitor C1; a first current-carrying line 110 is connected to one end of the trip coil Lx, the other end of the trip coil Lx is connected to the anode of the thyristor Q3, the cathode of the thyristor Q3 is connected to the anode of the first diode D1, and the cathode of the first diode D1 is connected to the second current-carrying line 120; the collector of the first transistor Q1 and the collector of the second transistor Q2 are connected together and connected to one end of the twelfth resistor R12; the other end of the twelfth resistor R12 is connected to one end of the thirteenth resistor R13, one end of the first capacitor C1, and the control electrode of the thyristor Q3; the other end of the thirteenth resistor R13 and the other end of the first capacitor C1 are both connected to the connection point between the thyristor Q3 and the first diode D1.

[0061] In this embodiment, when a trip trigger signal is output from the collector of the first transistor Q1 or the collector of the second transistor Q2 to the thyristor drive module 421, the trip trigger signal charges the first capacitor C1 after passing through the twelfth resistor R12, and the potential of the control electrode of the thyristor Q3 rises. When the positive half-cycle of the AC power supply is reached, that is, when the level of the first current-carrying line 110 is greater than the level of the second current-carrying line 120, the thyristor Q3 is turned on, forming a strong current path of the first current-carrying line 110-trip coil Lx-thyristor Q3-first diode D1-second current-carrying line 120; the trip coil Lx generates a strong electromagnetic force, thereby driving the switch module 500 to disconnect the power connection between the input and output terminals of the power supply line.

[0062] Reference Figure 1 In some embodiments of the detection and protection device provided by the present invention, the trigger module 420 further includes a first varistor ZR1 connected in parallel with the silicon controlled rectifier Q3. It is understood that a varistor is a resistor with nonlinear current-voltage characteristics, mainly used for voltage clamping when the circuit is subjected to overvoltage, absorbing excess current to protect sensitive devices. Therefore, setting the first varistor ZR1 in parallel with the silicon controlled rectifier Q3 can protect the silicon controlled rectifier Q3 from damage.

[0063] Reference Figure 1 In some embodiments of the present invention, the detection and protection device also includes an indicator module 600 connected in parallel with the silicon controlled rectifier Q3. The indicator module 600 includes an eleventh resistor R11, a tenth resistor R10 and a light-emitting diode LED1 connected in series.

[0064] Reference Figure 1In some embodiments of the present invention, the detection and protection device further includes a lightning protection module 700. The lightning protection module 700 includes a second varistor ZR2, with its two ends connected to a first current-carrying line 110 and a second current-carrying line 120, respectively. It is understood that a varistor is a resistor with nonlinear volt-ampere characteristics, mainly used for voltage clamping when a circuit is subjected to overvoltage, absorbing excess current to protect sensitive devices. Therefore, placing a second varistor ZR2 before the first current-carrying line 110 and the second current-carrying line 120 can protect subsequent components in the detection and protection device from damage caused by lightning strikes.

[0065] Below, with Figure 1 The illustrated embodiments describe the operation of the detection and protection device provided by the present invention under various leakage and open circuit conditions: 1. When the first current-carrying line 110 leaks current to the first shielding conductor 130, a leakage signal is sent to the first transistor Q1 through the second detection terminal Y, causing the first transistor Q1 to conduct and output a trip trigger signal to the trigger module 420.

[0066] Specifically, after the first shielding conductor 130 receives the leakage signal, it refers to... Figure 3 As shown, on the one hand, the current flows from the first terminal a to the second detection terminal Y, and then from the second detection terminal Y to the second resistor R2, the third resistor R3, and the first diode D1 in sequence, so that the voltage received at the emitter of the first transistor Q1 is greater than the voltage at the base, thus turning on the first transistor Q1; on the other hand, there is also... Figure 3 Other current flow directions indicated by the arrows; After the first transistor Q1 is turned on, the leakage signal flows through the first transistor Q1 and from the collector of the first transistor Q1 to the twelfth resistor R12, charging the first capacitor C1. The voltage of the control electrode of the thyristor Q3 increases. When the positive half-cycle of the AC power supply arrives, that is, when the level of the first current-carrying line 110 is greater than the level of the second current-carrying line 120, the thyristor Q3 is turned on, forming a strong current path of first current-carrying line 110 - trip coil Lx - thyristor Q3 - first diode D1 - second current-carrying line 120. The trip coil Lx generates a strong electromagnetic force, which drives the switch module 500 to disconnect the power connection between the input and output terminals of the power supply line.

[0067] 2. When the second current-carrying line 120 leaks current to the second shielding conductor 140, a leakage signal is sent to the second transistor Q2 through the first detection terminal X, causing the second transistor Q2 to conduct and output a trip trigger signal to the trigger module 420.

[0068] Specifically, after the first shielding conductor 130 receives the leakage signal, it refers to... Figure 4As shown, the current provided by the DC power module 100 flows through the fourth resistor R4 to the second detection terminal Y, and then from the second detection terminal Y to the first terminal a of the first shielding conductor 130 and the fourth terminal of the second shielding conductor 140 respectively; on the other hand, it flows from the DC power terminal VDD to the second resistor R2, the third resistor R3 and the first diode D1 in sequence, and from the first detection terminal X to the emitter of the second transistor Q2, so that the emitter of the second transistor Q2 receives a voltage greater than the base voltage, causing the second transistor Q2 to conduct; in addition, there are also... Figure 4 Other current flow directions indicated by the arrows; After the second transistor Q2 is turned on, current flows through the second transistor Q2 and from the collector of the second transistor Q2 to the twelfth resistor R12, charging the first capacitor C1. The voltage of the control electrode of the thyristor Q3 increases. When the positive half-cycle of the AC power supply arrives, that is, when the level of the first current-carrying line 110 is greater than the level of the second current-carrying line 120, the thyristor Q3 is turned on, forming a strong current path of first current-carrying line 110 - trip coil Lx - thyristor Q3 - first diode D1 - second current-carrying line 120. The trip coil Lx generates a strong electromagnetic force, which drives the switch module 500 to disconnect the power connection between the input and output terminals of the power supply line.

[0069] 3. When the first shielding conductor 130 is open-circuited, an open-circuit signal is sent to the first transistor Q1 through the second detection terminal Y, causing the first transistor Q1 to conduct and output a trip trigger signal to the trigger module 420.

[0070] Specifically, after the first shielding conductor 130 becomes open-circuited, refer to Figure 5 As shown, the current provided by the DC power module 100 flows sequentially through the second resistor R2, the third resistor R3, and the first diode D1. Simultaneously, it flows through the fourth resistor R4 to the fourth terminal d of the second shielding conductor 140, and then through the second shielding conductor 140 to the seventh resistor R7 and the third diode D3. This causes the emitter of the first transistor Q1 to receive a voltage greater than the base voltage, thus turning on the first transistor Q1. Additionally, there are other... Figure 5 Other current flow directions indicated by the arrows; After the first transistor Q1 is turned on, the current flows from the second detection terminal Y through the first transistor Q1 and from the collector of the first transistor Q1 to the twelfth resistor R12, charging the first capacitor C1. The voltage of the control electrode of the thyristor Q3 increases. When the positive half-cycle of the AC power supply arrives, that is, when the level of the first current-carrying line 110 is greater than the level of the second current-carrying line 120, the thyristor Q3 is turned on, forming a strong current path of first current-carrying line 110 - trip coil Lx - thyristor Q3 - first diode D1 - second current-carrying line 120. The trip coil Lx generates a strong electromagnetic force, which drives the switch module 500 to disconnect the power connection between the input and output terminals of the power supply line.

[0071] 4. When the second shielding conductor 140 is open-circuited, an open-circuit signal is sent to the first transistor Q1 through the second detection terminal Y, causing the first transistor Q1 to conduct and output a trip trigger signal to the trigger module 420.

[0072] Specifically, after the second shielding conductor 140 becomes open-circuited, refer to Figure 6 As shown, the current provided by the DC power module 100 flows sequentially through the second resistor R2, the third resistor R3, and the first diode D1. Simultaneously, it flows through the fourth resistor R4 to the first terminal a of the first shielding conductor 130 and the fifth resistor R5, and then through the first shielding conductor 130 to the sixth resistor R6 and the second diode D2. This causes the emitter of the first transistor Q1 to receive a voltage greater than the base voltage, thus turning on the first transistor Q1. Additionally, there are other... Figure 6 Other current flow directions indicated by the arrows; After the first transistor Q1 is turned on, the current flows from the second detection terminal Y through the first transistor Q1 and from the collector of the first transistor Q1 to the twelfth resistor R12, charging the first capacitor C1. The voltage of the control electrode of the thyristor Q3 increases. When the positive half-cycle of the AC power supply arrives, that is, when the level of the first current-carrying line 110 is greater than the level of the second current-carrying line 120, the thyristor Q3 is turned on, forming a strong current path of first current-carrying line 110 - trip coil Lx - thyristor Q3 - first diode D1 - second current-carrying line 120. The trip coil Lx generates a strong electromagnetic force, which drives the switch module 500 to disconnect the power connection between the input and output terminals of the power supply line.

[0073] 5. When the test switch TEST is pressed: a current signal is sent to the first transistor Q1 through the second detection terminal Y, so that the first transistor Q1 is turned on, and a trip trigger signal is output to the trigger module 420.

[0074] Specifically, after the test switch TEST is pressed, refer to Figure 7 As shown, the current supplied by the test switch TEST and the first resistor R1 flows sequentially through the fourth resistor R4, the second resistor R2, the third resistor R3, and the first diode D1. Simultaneously, it flows to the first terminal a of the first shielding conductor 130 and the fourth terminal d of the second shielding conductor 140, then through the first shielding conductor 130 to the sixth resistor R6 and the second diode D2, and through the second shielding conductor 140 to the seventh resistor R7 and the third diode D3. This causes the emitter of the first transistor Q1 to receive a voltage greater than the base voltage, thus turning on the first transistor Q1. Additionally, there are other... Figure 7 Other current flow directions indicated by the arrows; After the first transistor Q1 is turned on, the current flows from the second detection terminal Y through the first transistor Q1 and from the collector of the first transistor Q1 to the twelfth resistor R12, charging the first capacitor C1. The voltage of the control electrode of the thyristor Q3 increases. When the positive half-cycle of the AC power supply arrives, that is, when the level of the first current-carrying line 110 is greater than the level of the second current-carrying line 120, the thyristor Q3 is turned on, forming a strong current path of first current-carrying line 110 - trip coil Lx - thyristor Q3 - first diode D1 - second current-carrying line 120. The trip coil Lx generates a strong electromagnetic force, which drives the switch module 500 to disconnect the power connection between the input and output terminals of the power supply line.

[0075] Reference Figure 1 In some embodiments of the present invention, the first transistor Q1 and the second transistor Q2 are PNP transistors.

[0076] The power cord detection and protection device provided in this embodiment of the invention, under the action of the DC detection current provided by the DC power module 100, the first self-test unit 210, the second self-test unit 220 and the third self-test unit 230 in the self-test path module, together with the first shielding conductor 130 and the second shielding conductor 140, form a self-test path, and is provided with a first detection terminal X and a second detection terminal Y. When there is no leakage or open circuit, the potential of the first detection terminal X and the second detection terminal Y is constant and will not trigger the response processing module to act; when leakage or open circuit occurs, the potential of the first detection terminal X and the second detection terminal Y changes, which will trigger the response processing module to act, thereby disconnecting the power connection between the input and output terminals of the power cord, ensuring the power supply safety of the power cord; this power cord detection and protection device can effectively and reliably realize leakage detection of the power cord and open circuit detection of the shielding conductor of the power cord.

[0077] Reference Figure 8 A second aspect of the present invention provides an electrical connection device 800, including a detection and protection device as described in the first aspect embodiment above, a housing 810, and a power cord. The power cord is connected to the housing 810, and a DC power module 100, a first self-test unit 210, a second self-test unit 220, and a response processing module are disposed in the housing.

[0078] In addition, a third aspect of the present invention provides an electrical device including a load device and an electrical connection device 800 as described in the second aspect of the present invention, wherein the output end of a power line is connected to the load device.

[0079] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. A power cord detection and protection device, characterized in that, The power line includes a first current-carrying wire, a second current-carrying wire, a first shielding conductor covering the first current-carrying wire, and a second shielding conductor covering the second current-carrying wire. The detection and protection device includes: A DC power supply module is electrically connected to one end of the first shielding conductor and / or one end of the second shielding conductor, and is used to provide a DC detection current to the first shielding conductor and / or the second shielding conductor; The self-test path module, wherein the other end of the first shielding conductor and the other end of the second shielding conductor are electrically connected to the ground terminal through the self-test path module; The response processing module is electrically connected to the self-test path module and is used to disconnect the power connection between the input and output terminals of the power line in the event that the first shielding conductor is open, the second shielding conductor is open, the first shielding conductor detects a leakage signal and / or the second shielding conductor detects a leakage signal.

2. The detection and protection device according to claim 1, characterized in that, The DC power module is provided with a DC power terminal; The self-test path module includes a first self-test unit, a second self-test unit, and a third self-test unit; the first self-test unit is electrically connected between the DC power supply terminal and the ground terminal, and is provided with a first detection terminal; the second self-test unit is electrically connected to the first self-test unit and is provided with a second detection terminal, the second detection terminal being electrically connected to one end of the first shielding conductor and one end of the second shielding conductor respectively; the third self-test unit is electrically connected to the other end of the first shielding conductor, the other end of the second shielding conductor, and the ground terminal respectively. The response processing module is electrically connected to the first detection terminal, the second detection terminal, the first current-carrying line, and the second current-carrying line, respectively.

3. The detection and protection device according to claim 2, characterized in that, It also includes a test module, which includes a test switch and a first resistor, one end of which is connected to one end of the first resistor; The other end of the test switch is connected to one of the first current-carrying line, the second current-carrying line, and the DC power supply terminal. The other end of the first resistor is connected to one of the first detection terminal, the second detection terminal, the first shielding conductor, and the second shielding conductor.

4. The detection and protection device according to claim 2, characterized in that, The first self-test unit includes a second resistor, a third resistor, and a first diode connected in sequence; the second resistor is connected to the DC power supply terminal, and the cathode of the first diode is connected to the ground terminal; the connection point of the second resistor and the third resistor serves as the first detection terminal.

5. The detection and protection device according to claim 4, characterized in that, The second self-test unit includes a fourth resistor and a fifth resistor connected in sequence. The fourth resistor is connected to the DC power supply terminal, and the fifth resistor is connected to the anode of the first diode. The connection point of the fourth resistor and the fifth resistor serves as the second detection terminal.

6. The detection and protection device according to claim 5, characterized in that, The third self-test unit includes a sixth resistor and a seventh resistor; the two ends of the sixth resistor are respectively connected to the other end of the first shielding conductor and the ground terminal, and the two ends of the seventh resistor are respectively connected to the other end of the second shielding conductor and the ground terminal.

7. The detection and protection device according to claim 6, characterized in that, The third self-test unit further includes a second diode and a third diode. The sixth resistor is connected to the anode of the second diode, the seventh resistor is connected to the anode of the third diode, and the cathodes of the second diode and the third diode are connected to the ground terminal.

8. The detection and protection device according to claim 2, characterized in that, The DC power supply module uses an isolated power supply, and the DC power supply terminal is electrically connected to the self-test path module, the first shielding conductor, and the second shielding conductor to form a low-voltage DC self-test path.

9. The detection and protection device according to claim 8, characterized in that, An isolation field is formed inside the isolation power supply to isolate the input current from the output current.

10. The detection and protection device according to claim 2, characterized in that, The response processing module includes a fault response module and a trigger module. The fault response module is connected to the first detection terminal, the second detection terminal and the trigger module respectively. The trigger module is connected to the fault response module, the first current-carrying line and the second current-carrying line respectively. The fault response module is used to acquire the open circuit signal generated when the first shielding conductor and / or the second shielding conductor is open, and to acquire the leakage current signal detected by the first shielding conductor and / or the second shielding conductor, and to output a trip trigger signal in response to the open circuit signal or the leakage current signal. The trigger module is configured to disconnect the power connection between the input and output terminals of the power line via a switch module in response to receiving the trip trigger signal.

11. The detection and protection device according to claim 10, characterized in that, The fault response module includes a first transistor, a second transistor, an eighth resistor, a ninth resistor, and a tenth resistor; The emitter of the first transistor is connected to one end of the eighth resistor, the base of the second transistor is connected to one end of the ninth resistor, and the emitter of the second transistor is connected to one end of the tenth resistor. The base of the first transistor and the other end of the tenth resistor are both connected to the first detection terminal; the other ends of the eighth resistor and the ninth resistor are both connected to the second detection terminal. The collectors of the first transistor and the second transistor are connected together and connected to the trigger module to output the trip trigger signal to the trigger module.

12. The detection and protection device according to claim 11, characterized in that, When the first current-carrying line leaks current to the first shielding conductor, a leakage signal is sent to the first transistor through the second detection terminal, causing the first transistor to conduct and output the trip trigger signal to the trigger module.

13. The detection and protection device according to claim 11, characterized in that, When the second current-carrying line leaks current to the second shielding conductor, a leakage signal is sent to the second transistor through the first detection terminal, causing the second transistor to conduct and output the trip trigger signal to the trigger module.

14. The detection and protection device according to claim 11, characterized in that, When the first shielding conductor and / or the second shielding conductor are open-circuited, an open-circuit signal is sent to the first transistor through the second detection terminal, causing the first transistor to conduct and output the trip trigger signal to the trigger module.

15. The detection and protection device according to claim 11, characterized in that, The first transistor and the second transistor are PNP type transistors.

16. An electrical connection device, characterized in that, The device includes the detection and protection device as described in any one of claims 2 to 15, a housing, and the power cord, wherein the power cord is connected to the housing, and the DC power module, the first self-test unit, the second self-test unit, and the response processing module are disposed in the housing.

17. An electrical appliance, characterized in that, It includes a load device and the electrical connection device as described in claim 16, wherein the output end of the power line is connected to the load device.

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