CN113791342B - Switching device and electric appliance - Google Patents

Abstract

The application provides a switching device and an electric appliance, wherein the switching device comprises a decoupling circuit, a relay switch, a protection circuit, a zero-crossing detection circuit and a control unit, wherein the decoupling circuit is used for receiving alternating current and decoupling the alternating current; the input end of the relay switch is electrically connected with the output end of the decoupling circuit, and the output end of the relay switch is used for being electrically connected with a load; the protection circuit is connected with the relay switch in parallel, and is used for limiting and discharging an electric arc generated in the switching state change process of the relay switch, and the conducting voltage of the protection circuit is larger than that of alternating current; the zero-crossing detection circuit is used for carrying out zero-crossing detection on the alternating current and outputting a detection result; the control unit is electrically connected with the output end of the zero-crossing detection circuit and the control end of the relay switch respectively, and is used for receiving the switch control instruction and the detection result and controlling the switch state of the relay switch according to the switch control instruction and the detection result.

Description

Switching devices and electrical appliances

Technical field

The present application relates to the field of switches, specifically, to a switching device and electrical appliances.

Background technique

Whether it is a mechanical switch or an electronic switch, the core is the contact. The contact capability affects the life of the switch. The mechanical life of the switch is very high. However, due to the influence of voltage and current after powering on, the electrical life of the switch is much lower than the mechanical life.

At the moment of turning on and off, the sudden change in voltage between switches causes an arc to occur at the distance between the switch electrodes, and the type of load after the switch also has a greater influence. For example, the discharge of capacitive loads, the reverse electromotive force of the motor, etc. all cause the switch to turn on and off at the instant More prone to arcing.

In the existing technology, the AC switch detects the AC zero phase, detects the relay pull-in time, calculates the compensation relay pull-in time, and commands the relay switch to instantly pull in the zero phase, so that the instantaneous voltage pulls in the zero-crossing state during the switch. , the voltage is relatively lowest at zero phase, which achieves switch arc extinguishing and increases the electrical life of the switch. However, the pull-in time of the relay is detected for control and compensation. The detected pull-in time is in the past tense. The pull-in time of the relay is not fixed every time, resulting in poor arc suppression effect.

Therefore, how to suppress the generation of arcs to ensure the electrical life of the switch is an urgent problem that needs to be solved in the existing technology.

The above information disclosed in this Background section is only used to enhance understanding of the background of the technology described herein. Therefore, the Background may contain certain information that would not be known in this country to a person skilled in the art. Known existing technology.

Contents of the invention

The main purpose of this application is to provide a switching device and electrical appliance to solve the problem in the prior art that arc is generated at the moment when the switch is turned on and off, which affects the service life of the switch.

According to one aspect of the present application, a switching device is provided, including a decoupling circuit, a relay switch, a protection circuit, a zero-crossing detection circuit, and a control unit, wherein the decoupling circuit is used to receive alternating current, and to process the alternating current. Decoupling; the relay switch includes an input end, an output end and a control end, the input end of the relay switch is electrically connected to the output end of the decoupling circuit, and the output end of the relay switch is used to electrically connect with the load; The protection circuit is connected in parallel with the relay switch, the protection circuit is used to limit and discharge the arc generated during the switching state change process of the relay switch, and the conduction voltage of the protection circuit is greater than the alternating current; The zero-crossing detection circuit is used to perform zero-crossing detection on the alternating current and output detection results; the control unit is electrically connected to the output end of the zero-crossing detection circuit and the control end of the relay switch, respectively. The control unit is configured to receive a switch control instruction and the detection result, and control the switching state of the relay switch according to the switch control instruction and the detection result.

Optionally, the relay switch includes a first switch circuit and a second switch circuit, the first switch circuit includes a first relay, the first relay includes a first input circuit, and the second switch circuit includes a second Relay, the second relay includes a second input circuit, the first end of the first input circuit is electrically connected to the output end of the decoupling circuit, the second end of the first input circuit is connected to the second The first end of the input loop is electrically connected, and the second end of the second input loop is used to be electrically connected to the load. The protection circuit includes a voltage relief subcircuit and a current limiting subcircuit. The voltage relief subcircuit The circuit is connected in parallel with the first input loop, the conduction voltage of the voltage discharge sub-circuit is greater than the alternating current, and the current limiting sub-circuit is connected in parallel with the second input loop.

Optionally, the first relay further includes a first output circuit, and the first switching circuit further includes a first switching tube, a second switching tube, a first voltage dividing element and a second voltage dividing element, wherein, the The first end of the first switch tube is electrically connected to the first end of the first output circuit, and the first end of the first switch tube is also used to be electrically connected to an external power supply; the second switch tube includes three terminal, the first end of the second switching tube is electrically connected to the second end of the first switching tube, the second end of the second switching tube is grounded; the first end of the first voltage dividing element is connected to The third end of the second switching tube is electrically connected, the second end of the first voltage dividing element is electrically connected to the control unit; the first end of the second voltage dividing element is electrically connected to the second switching tube. The third end and the first end of the first voltage dividing element are electrically connected respectively, and the second end of the second voltage dividing element is grounded.

Optionally, the voltage discharge sub-circuit includes a varistor and/or a TVS tube.

Optionally, the current limiting sub-circuit includes a third voltage dividing element.

Optionally, the zero-crossing detection circuit includes a first sub-detection circuit and a second sub-detection circuit, wherein the first sub-detection circuit includes a first optical coupler, and the first optical coupler includes a first light-emitting and a first light receiver, two ends of the first light emitter are electrically connected to the input end of the decoupling circuit, a first end of the first light receiver is electrically connected to the control unit, and the third The second end of a photoreceiver is grounded; the second sub-detection circuit includes a second optical coupler, the second optical coupler includes a second light emitter and a second light receiver, and the first end of the second light emitter is The second end of the second light receiver is electrically connected to the second end of the second input circuit, the second end of the second light emitter is electrically connected to the output end of the decoupling circuit, and the first end of the second light receiver is electrically connected to the second end of the second light receiver. The control unit is electrically connected, and the second end of the second light receiver is grounded.

Optionally, the control unit includes a light-emitting device and a single-chip microcomputer, the first end of the light-emitting device is grounded; the single-chip computer is electrically connected to the relay switch, the zero-crossing detection circuit and the light-emitting device respectively, and the The microcontroller is used to control the switching state of the relay switch according to the switch control instruction and the detection result, and to control the lighting state of the light-emitting device according to the lighting state of the relay switch.

Optionally, the switching device further includes a power supply circuit, the input end of the power supply circuit is electrically connected to the output end of the decoupling circuit, and the output end of the power supply circuit is connected to the zero-crossing detection circuit and the control circuit. The units are electrically connected respectively, and the power supply circuit is used to convert the decoupled alternating current into direct current, and the voltage of the direct current is smaller than the voltage of the alternating current.

Optionally, the power supply circuit includes a resistor-capacitor step-down subcircuit, an isolated power supply, a non-isolated power supply, or a low-dropout linear voltage regulator.

According to another aspect of the present application, an electrical appliance is also provided, including any one of the switching devices described above.

Applying the technical solution of this application, the switching device includes a decoupling circuit, a relay switch, a protection circuit, a zero-crossing detection circuit and a control unit. The decoupling circuit decouples the alternating current from the alternating current; the relay switch is respectively connected to The decoupling circuit and the load are electrically connected to perform switching actions; the zero-crossing detection circuit detects the voltage zero point of the alternating current; the control unit is used to receive switching control instructions and is also used to receive signals from the zero-crossing detection circuit. The detection result is used to control the on and off of the relay switch according to the switch control instruction and the detection result; the protection circuit is used to protect the relay switch and protect the arc when the relay switch is on and off. Limit and release. The switching device, through the control unit, ensures that the relay switch basically performs on-off transition in the zero-crossing state, ensuring that the voltage during on-off is low, and when an arc occurs, the arc is limited and protected by the protection circuit. Discharge reduces arc damage to switching devices, thereby ensuring a longer service life of switching devices. Moreover, the switching device filters out voltage fluctuations of the alternating current through the decoupling circuit, ensuring better performance of the switching device.

Description of drawings

The description and drawings that constitute a part of this application are used to provide a further understanding of this application. The illustrative embodiments and their descriptions of this application are used to explain this application and do not constitute an improper limitation of this application. In the attached picture:

Figure 1 shows a schematic diagram of a switching device according to an embodiment of the present application;

Figure 2 shows a schematic structural diagram of a first switch circuit and a voltage discharge subcircuit according to an embodiment of the present application;

Figure 3 shows a schematic structural diagram of a second switch circuit and a current limiting subcircuit according to an embodiment of the present application;

Figure 4 shows a schematic structural diagram of a first sub-detection circuit according to an embodiment of the present application;

Figure 5 shows a schematic structural diagram of a second sub-detection circuit according to an embodiment of the present application;

Figure 6 shows a schematic diagram of a control unit according to an embodiment of the present application;

Figure 7 shows a schematic structural diagram of a power supply circuit according to an embodiment of the present application;

Figure 8 shows a schematic structural diagram of a decoupling circuit according to an embodiment of the present application.

Among them, the above-mentioned drawings include the following reference signs:

10. Decoupling circuit; 20. Relay switch; 30. Protection circuit; 40. Zero-crossing detection circuit; 50. Control unit; 60. Power supply circuit; 200. First switching circuit; 201. Second switching circuit; 202. No. An input loop; 203, the first output loop; 204, the second input loop; 205, the second output loop; 300, voltage discharge sub-circuit; 301, current limiting sub-circuit; 400, first sub-detection circuit; 401. The second sub-detection circuit.

Detailed ways

It should be noted that the following detailed description is illustrative and is intended to provide further explanation of the present application. Unless otherwise defined, all technical and scientific terms used herein have the same meanings commonly understood by one of ordinary skill in the art to which this application belongs.

It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, the singular forms are also intended to include the plural forms unless the context clearly indicates otherwise. Furthermore, it will be understood that when the terms "comprises" and/or "includes" are used in this specification, they indicate There are features, steps, operations, means, components and/or combinations thereof.

It will be understood that when an element (such as a layer, film, region, or substrate) is referred to as being "on" another element, it can be directly on the other element or intervening elements may also be present. Furthermore, in the specification and claims, when an element is described as being "connected" to another element, it can be "directly connected" to the other element, or "connected" to the other element through a third element.

As introduced in the background art, in the prior art, an arc is generated at the instant when the switch is turned on and off, which affects the service life of the switch. In order to solve the above problems, this application proposes a switching device and electrical appliance.

According to a typical embodiment of the present application, a switching device is provided. As shown in Figure 1, the switching device includes a decoupling circuit 10, a relay switch 20, a protection circuit 30, a zero-crossing detection circuit 40 and a control unit 50. , wherein the above-mentioned decoupling circuit 10 is used to receive alternating current and decouple the above-mentioned alternating current; the above-mentioned relay switch 20 includes an input end, an output end and a control end, and the input end of the above-mentioned relay switch 20 and the output end of the above-mentioned decoupling circuit 10 Electrical connection, the output end of the above-mentioned relay switch 20 is used to be electrically connected to the load; the above-mentioned protection circuit 30 is connected in parallel with the above-mentioned relay switch 20, and the above-mentioned protection circuit 30 is used to limit the arc generated during the switching state change process of the above-mentioned relay switch 20 and Discharge, and the conduction voltage of the above-mentioned protection circuit is greater than the above-mentioned alternating current; the above-mentioned zero-crossing detection circuit 40 is used to perform zero-crossing detection on the above-mentioned alternating current and output the detection result; the output terminals of the above-mentioned control unit 50 and the above-mentioned zero-crossing detection circuit 40 The control end of the relay switch 20 is electrically connected respectively. The control unit 50 is configured to receive the switch control instruction and the detection result, and control the switching state of the relay switch 20 according to the switch control instruction and the detection result.

The above-mentioned switching device includes a decoupling circuit, a relay switch, a protection circuit, a zero-crossing detection circuit and a control unit. The above-mentioned decoupling circuit decouples the alternating current from the alternating current; the above-mentioned relay switch is electrically connected to the above-mentioned decoupling circuit and the load respectively. Used to perform switching actions; the above-mentioned zero-crossing detection circuit detects the voltage zero point of the above-mentioned alternating current; the above-mentioned control unit is used to receive switch control instructions, and is also used to receive the detection results of the zero-crossing detection circuit, and according to the above-mentioned switch control instructions and the above-mentioned detection results , to control the on-off of the above-mentioned relay switch; the above-mentioned protection circuit is used to protect the above-mentioned relay switch, and limit and discharge the arc when the arc is generated when the relay switch is on-off. The above-mentioned switching device, through the above-mentioned control unit, ensures that the relay switch basically performs on-off switching in the zero-crossing state, ensuring a low voltage during on-off. When an arc occurs, the above-mentioned protection circuit limits and discharges the arc. The arc damage to the switching device is alleviated, thereby ensuring a longer service life of the switching device. Moreover, the above-mentioned switching device filters out the voltage fluctuation of the above-mentioned alternating current through the above-mentioned decoupling circuit, ensuring better performance of the switching device.

It should be noted that the above AC power is commercial power.

In the actual application process, the power of the above-mentioned load electrically connected to the switching device will also affect the size of the arc generated by the switching device. In this case, in order to further ensure that the arc during the operation of the above-mentioned switching device is basically suppressed, Thereby further ensuring a longer service life of the above-mentioned switching device. According to a specific embodiment of the present application, as shown in Figures 1, 2 and 3, the above-mentioned relay switch 20 includes a first switch circuit 200 and a second switch. Circuit 201. The first switch circuit 200 includes a first relay JDQ1. The first relay JDQ1 includes a first input circuit 202. The second switch circuit 201 includes a second relay JDQ2. The second relay JDQ2 includes a second input circuit 204. , the first end of the above-mentioned first input loop 202 is electrically connected to the output end of the above-mentioned decoupling circuit 10, the second end of the above-mentioned first input loop 202 is electrically connected to the first end of the above-mentioned second input loop 204, and the above-mentioned second The second end of the input circuit 204 is used to be electrically connected to the load. The protection circuit 30 includes a voltage discharge sub-circuit 300 and a current limiting sub-circuit 301. The voltage discharge sub-circuit 300 is connected in parallel with the first input circuit 202. The conduction voltage of the voltage discharge subcircuit is greater than the AC current, and the current limiting subcircuit 301 is connected in parallel with the second input circuit 204 . By setting up two series-connected switching circuits, as well as a series-connected voltage discharge sub-circuit and a current-limiting sub-circuit, the above-mentioned voltage discharge sub-circuit can perform voltage limiting detection and discharge protection on the circuit generated during the switching process. The current limiting sub-circuit can delay the switching action, causing the current of the circuit to gradually change, which further ensures that the arc generated is smaller, thus ensuring that the size of the terminal load or alternating current has less impact on the above-mentioned switching devices, thereby further ensuring that the This ensures that the arc is basically voltage-limited and discharged when the switching device is turned on and off.

Specifically, when the above-mentioned switching device changes from a closed state to an on-state, the above-mentioned current limiting sub-circuit starts current limiting, the above-mentioned control unit first controls the above-mentioned first switching circuit to close (open) when the alternating current zero crosses, and the above-mentioned first switch The current-limiting module of the circuit limits the circuit to a low-voltage and low-current state, synchronizes the above-mentioned voltage discharge sub-circuit to discharge the arc generated when the above-mentioned first switch circuit is closed, the above-mentioned switching device is in a current-limiting output state, and then the above-mentioned control unit controls The above-mentioned second switch circuit is activated when the alternating current crosses zero. At this time, the entire switching device can output a larger current, and the above-mentioned current limiting sub-circuit is opened to perform discharge protection on the opening of the above-mentioned second switch circuit. When the above-mentioned switching device changes from the on-state to the off-state, the control unit first controls the above-mentioned second switch circuit to close when the alternating current crosses zero, the above-mentioned current limiting sub-circuit performs discharge protection on the above-mentioned second switch circuit, and the above-mentioned second switch circuit closes Finally, the above-mentioned current limiting sub-circuit limits the large current output and divides the voltage to keep the above-mentioned first switch circuit in a low-voltage state. Then the above-mentioned control unit controls the above-mentioned first switch circuit to close when the alternating current crosses zero, and the above-mentioned voltage discharge sub-circuit The arc generated by the above-mentioned first switch circuit when closed is subjected to pressure limiting and discharge protection. And since the conduction voltage of the voltage discharge sub-circuit is greater than the alternating current, when the first switch circuit and/or the second switch circuit are in an off state, no current flows through the switch device.

In another specific embodiment of the present application, as shown in Figure 2, the above-mentioned first relay JDQ1 also includes a first output circuit 203, and the above-mentioned first switch circuit also includes a first switch tube D4, a second switch tube Q1, The first voltage dividing element R11 and the second voltage dividing element R13, wherein the first end of the first switching tube D4 is electrically connected to the first end of the first output circuit 203, and the first end of the first switching tube D4 It is also used for electrical connection with an external power supply; the second switch tube Q1 includes three terminals, and the first end of the second switch tube Q1 is electrically connected to the second end of the first switch tube D4. The second switch tube Q1 The second end of the first voltage dividing element R11 is electrically connected to the third end of the second switching tube Q1, and the second end of the first voltage dividing element R11 is connected to the pin REALY1 of the control unit. Electrical connection; the first end of the second voltage dividing element R13 is electrically connected to the third end of the second switching tube Q1 and the first end of the first voltage dividing element R11 respectively, and the third end of the second voltage dividing element R13 is electrically connected. Both ends are grounded. The control unit controls the switching state of the first switching circuit by controlling the switching state of the second switching tube.

In yet another specific embodiment of the present application, as shown in Figure 3, the above-mentioned second relay JDQ2 also includes a second output circuit 205, and the above-mentioned second switch circuit also includes a third switching tube D5, a fourth switching tube Q2, The fourth voltage dividing element R12 and the fifth voltage dividing element R14, wherein the first end of the third switching tube D5 is electrically connected to the first end of the second output circuit 205, and the first end of the third switching tube D5 It is also used for electrical connection with an external power supply; the fourth switching tube Q2 includes three terminals, and the first end of the fourth switching tube Q2 is electrically connected to the second end of the third switching tube D5. The fourth switching tube Q2 The second end of the fourth voltage dividing element R12 is electrically connected to the third end of the fourth switching tube Q2, and the second end of the fourth voltage dividing element R12 is electrically connected to the pin REALY2 of the control unit. Electrically connected; the first end of the fifth voltage dividing element R14 is electrically connected to the third end of the fourth switching tube Q2 and the first end of the fourth voltage dividing element R12 respectively, and the third end of the fifth voltage dividing element R14 is electrically connected. Both ends are grounded. The control unit controls the switching state of the second switching circuit by controlling the switching state of the fourth switching tube.

In another specific embodiment, as shown in Figures 2 and 3, the first switch D4 is a first diode, the second switch Q1 is a first transistor, and the third switch D5 is a second diode, the fourth switching tube Q2 is a second transistor, the first voltage dividing element R11 is a first resistor, the second voltage dividing element R13 is a second resistor, and the fourth voltage dividing element R12 is the fourth resistor, and the fifth voltage dividing element R14 is the fifth resistor. The cathode of the first diode is electrically connected to the external power supply, the anode of the first diode is electrically connected to the first end of the first output circuit; the base of the first transistor is the second switching tube. The third terminal of the above-mentioned first triode is the first terminal of the above-mentioned second switching tube, and the emitter of the above-mentioned first triode is the second terminal of the above-mentioned second switching tube; the above-mentioned second diode The anode of the above-mentioned second output circuit is electrically connected to the first terminal of the above-mentioned second output circuit, the cathode of the above-mentioned second diode is electrically connected to the above-mentioned external power supply; the base of the above-mentioned second transistor is the third terminal of the above-mentioned fourth switching tube, and the above-mentioned The collector of the second transistor is the first terminal of the fourth switch, and the emitter of the second transistor is the second terminal of the fourth switch.

In actual application process, the above-mentioned voltage discharge sub-circuit can be any feasible voltage clamping discharge circuit in the prior art, and the above-mentioned current limiting sub-circuit can also be any feasible current limiting circuit in the prior art. This field Technicians can flexibly select the above-mentioned voltage discharge sub-circuit and the above-mentioned current limiting sub-circuit according to the actual situation. In a specific embodiment, the voltage discharging sub-circuit includes a varistor and/or a TVS tube, and the current limiting sub-circuit includes a third voltage dividing element. In a more specific embodiment, as shown in Figures 2 and 3, the voltage discharge sub-circuit is a varistor RV2, the current limiting sub-circuit is the third voltage dividing element R31, and the third voltage dividing element Component R31 is the third resistor.

In the actual application process, the above-mentioned alternating current is commercial power (220V), and the conduction voltage of the above-mentioned varistor and the above-mentioned TVS tube is generally set to 300V.

According to another specific embodiment of the present application, as shown in Figure 1, Figure 3 to Figure 5, the above-mentioned zero-crossing detection circuit 40 includes a first sub-detection circuit 400 and a second sub-detection circuit 401, wherein the above-mentioned first sub-detection circuit 400 The sub-detection circuit 400 includes a first optical coupler U3. The first optical coupler U3 includes a first light emitter and a first light receiver. Both ends of the first light emitter are electrically connected to the input ends of the decoupling circuit 10 respectively. , the first end of the above-mentioned first light receiver is electrically connected to the pin ZERO1 of the above-mentioned control unit, and the second end of the above-mentioned first light receiver is grounded; the above-mentioned second sub-detection circuit 401 includes a second optical coupler U4, and the above-mentioned second The optical coupler includes a second light emitter and a second light receiver. The first end of the second light emitter is electrically connected to the second end of the second input loop 204 . The second end of the second light emitter is electrically connected to the decoupling device. The output end of the circuit 10 is electrically connected, the first end of the second light receiver is electrically connected to the pin ZERO2 of the control unit, and the second end of the second light receiver is grounded. The above-mentioned zero-crossing detection circuit detects the voltage signal at the mains input terminal before decoupling through the above-mentioned first sub-detection circuit, and detects the voltage signal at the mains output terminal after the relay switch through the above-mentioned second sub-detection circuit. The above-mentioned control unit detects the voltage signal at the mains input terminal after the relay switch. The signal is calculated to obtain the voltage zero point mentioned above. The zero-crossing signal is detected through the photoelectric isolation device, which further ensures that the detection result of the zero-crossing signal is relatively accurate, thereby further ensuring that the above-mentioned control unit can basically control the switching action of the above-mentioned relay at the zero voltage point, further ensuring that the generated arc smaller.

Specifically, the above-mentioned first sub-detection circuit and the above-mentioned second sub-detection circuit may be the same or different. The above-mentioned first sub-detection circuit and the above-mentioned second sub-detection circuit can be any suitable zero-crossing detection circuit in the prior art. Those skilled in the art can flexibly set the above-mentioned first sub-detection circuit and the above-mentioned second sub-detection circuit according to actual needs. . In yet another specific embodiment of the present application, the above-mentioned first sub-detection circuit also includes a sixth resistor R16, a seventh resistor R17, an eighth resistor R18, a ninth resistor R15, a first capacitor C10 and a third diode. D6, its connection relationship is shown in Figure 4. The above-mentioned second sub-detection circuit also includes a tenth resistor R20, an eleventh resistor R21, a twelfth resistor R22, a thirteenth resistor R19, a second capacitor C11 and a fourth diode D7. The connection relationship is as shown in Figure 5 Show.

According to another specific embodiment of the present application, as shown in Figure 6, the above-mentioned control unit includes a light-emitting device LED and a single-chip microcomputer U1. The first end of the above-mentioned light-emitting device LED is grounded; the above-mentioned single-chip computer U1, the above-mentioned relay switch, and the above-mentioned zero-crossing The detection circuit and the light-emitting device are electrically connected respectively. The microcontroller U1 is used to control the switching state of the relay switch according to the switch control instruction and the detection result, and to control the lighting state of the light-emitting device LED according to the lighting state of the relay switch. In this way, whether the above-mentioned relay switch is conductive is displayed by whether the above-mentioned light-emitting device is on or off, which facilitates the user to understand the switching state of the above-mentioned switch device.

In a more specific embodiment, as shown in Figure 6, the above-mentioned microcontroller U1 includes 8 pins, namely pin REALY1, pin REALY2, pin ZERO1, pin ZERO2, pin 1, and pin 8. , pin 5 and pin 6. The above-mentioned control unit also includes a third capacitor C6, a sixth voltage dividing element R8, a seventh voltage dividing element R10 and a contact KEY. Both ends of the above-mentioned third capacitor C6 are connected to the above-mentioned pins respectively. 1 and the above-mentioned pin 8, the above-mentioned pin 1 is also used to connect the external power supply, the above-mentioned pin 8 is also used for grounding, the above-mentioned pin REALY1 and the above-mentioned pin REALY2 are respectively used to connect the control end of the above-mentioned first switch circuit and the above-mentioned The control end of the second switch circuit, the above-mentioned pin ZERO1 and the above-mentioned pin ZERO2 are electrically connected to the output end of the above-mentioned first sub-detection circuit and the above-mentioned second sub-detection circuit respectively, the above-mentioned pin 6 and the above-mentioned sixth voltage divider The first end of the component R8 is electrically connected, the second end of the above-mentioned sixth voltage dividing element R8 is electrically connected to the first end of the above-mentioned contact KEY, the second end of the above-mentioned contact KEY is grounded, and the above-mentioned pin 5 is connected to the above-mentioned seventh The voltage dividing element R10 and the above-mentioned light-emitting device LED are connected in series in sequence.

In actual application process, as shown in Figure 1, the above-mentioned switching device also includes a power supply circuit 60. The input end of the above-mentioned power supply circuit 60 is electrically connected to the output end of the above-mentioned decoupling circuit 10. The output end of the above-mentioned power supply circuit 60 is connected to the above-mentioned decoupling circuit 10. The zero-crossing detection circuit 40 and the control unit 50 are electrically connected respectively. The power supply circuit 60 is used to convert the decoupled alternating current into direct current, and the voltage of the direct current is smaller than the voltage of the alternating current. The above-mentioned power supply circuit is used to supply power to the above-mentioned zero-crossing detection circuit and the above-mentioned control unit.

In a specific embodiment, the power supply circuit includes a resistor-capacitor step-down subcircuit, an isolated power supply, a non-isolated power supply or a low-voltage linear regulator. Of course, the above-mentioned power supply circuit is not limited to the above-mentioned circuit. The above-mentioned power supply circuit can also be any feasible step-down AC-DC conversion circuit in the prior art. For example, resistance analysis and other methods are used to realize the function of the above-mentioned power supply circuit. This application shows a power supply circuit structure diagram as shown in Figure 7. In addition, the above-described decoupling circuit of this application can also be any feasible decoupling circuit in the prior art. This application provides a structural diagram of a decoupling circuit as shown in Figure 8.

According to another typical embodiment of the present application, an electrical appliance is also provided, including any one of the above switching devices.

The above-mentioned electrical appliances include any one of the above-mentioned switching devices. The above-mentioned switching device ensures that the relay switch basically performs on-off switching in the zero-crossing state through the above-mentioned control unit, ensuring that the voltage during on-off is low, and when an arc occurs, The above-mentioned protection circuit limits and discharges the arc, thereby mitigating the damage caused by the arc to the switching device, thereby ensuring a long service life of the switching device. Moreover, the above-mentioned switching device filters out the voltage fluctuation of the above-mentioned alternating current through the above-mentioned decoupling circuit, ensuring better performance of the switching device.

In actual application, the above-mentioned electrical appliances may be sockets or charging piles that require electronic switch control. Of course, they may also be other electrical appliances with the above-mentioned switching devices, which will not be described again here.

From the above description, it can be seen that the above-mentioned embodiments of the present application achieve the following technical effects:

1). The above-mentioned switching device in this application includes a decoupling circuit, a relay switch, a protection circuit, a zero-crossing detection circuit and a control unit. The above-mentioned decoupling circuit decouples the alternating current; the above-mentioned relay switch is connected to the above-mentioned decoupling circuit and load respectively. Electrical connection, used to perform switching actions; the above-mentioned zero-crossing detection circuit detects the voltage zero point of the above-mentioned alternating current; the above-mentioned control unit is used to receive switch control instructions, and is also used to receive the detection results of the zero-crossing detection circuit, and according to the above-mentioned switch control instructions and The above detection results are used to control the on-off of the above-mentioned relay switch; the above-mentioned protection circuit is used to protect the above-mentioned relay switch and limit and discharge the arc when the arc is generated by the on-off of the relay switch. The above-mentioned switching device, through the above-mentioned control unit, ensures that the relay switch basically performs on-off switching in the zero-crossing state, ensuring a low voltage during on-off. When an arc occurs, the above-mentioned protection circuit limits and discharges the arc. The arc damage to the switching device is alleviated, thereby ensuring a longer service life of the switching device. Moreover, the above-mentioned switching device filters out the voltage fluctuation of the above-mentioned alternating current through the above-mentioned decoupling circuit, ensuring better performance of the switching device.

2). The above-mentioned electrical appliances in this application include any one of the above-mentioned switching devices. The above-mentioned switching device ensures that the relay switch basically performs on-off switching in the zero-crossing state through the above-mentioned control unit, ensuring that the voltage during on-off is low, and When an arc occurs, the arc is restricted and discharged through the above protection circuit, which alleviates the damage of the arc to the switching device, thus ensuring a long service life of the switching device. Moreover, the above-mentioned switching device filters out the voltage fluctuation of the above-mentioned alternating current through the above-mentioned decoupling circuit, ensuring better performance of the switching device.

The above descriptions are only preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of this application shall be included in the protection scope of this application.

Claims (9)

1. A switching device, characterized in that it includes: A decoupling circuit for receiving alternating current and decoupling said alternating current; Relay switch, the relay switch includes an input end, an output end and a control end, the input end of the relay switch is electrically connected to the output end of the decoupling circuit, and the output end of the relay switch is used to be electrically connected to the load; A protection circuit, connected in parallel with the relay switch, the protection circuit is used to limit and discharge the arc generated during the switching state change process of the relay switch, and the conduction voltage of the protection circuit is greater than the alternating current; A zero-crossing detection circuit is used to detect zero-crossing of the alternating current and output the detection result; A control unit is electrically connected to the output end of the zero-crossing detection circuit and the control end of the relay switch respectively. The control unit is used to receive the switch control instruction and the detection result, and perform the control according to the switch control instruction and the detection result. The detection results control the switching state of the relay switch, The relay switch includes a first switch circuit and a second switch circuit, the first switch circuit includes a first relay, the first relay includes a first input circuit, the second switch circuit includes a second relay, and the The second relay includes a second input loop, a first end of the first input loop is electrically connected to the output end of the decoupling circuit, and a second end of the first input loop is electrically connected to a third end of the second input loop. One end is electrically connected, and the second end of the second input loop is used to be electrically connected to the load, The protection circuit includes a voltage discharge sub-circuit and a current limiting sub-circuit. The voltage discharge sub-circuit is connected in parallel with the first input circuit. The conduction voltage of the voltage discharge sub-circuit is greater than the alternating current. The current limiting sub-circuit is connected in parallel with the second input loop. 2. The switching device according to claim 1, wherein the first relay further includes a first output circuit, and the first switching circuit further includes: A first switch tube, the first end of the first switch tube is electrically connected to the first end of the first output circuit, and the first end of the first switch tube is also used to be electrically connected to an external power supply; The second switch tube includes three terminals, the first end of the second switch tube is electrically connected to the second end of the first switch tube, and the second end of the second switch tube is grounded; A first voltage dividing element, the first end of the first voltage dividing element is electrically connected to the third end of the second switching tube, and the second end of the first voltage dividing element is electrically connected to the control unit; A second voltage dividing element, the first end of the second voltage dividing element is electrically connected to the third end of the second switching tube and the first end of the first voltage dividing element respectively. The second voltage dividing element The second terminal of the component is connected to ground. 3. The switching device according to claim 1, characterized in that the voltage discharge sub-circuit includes a varistor and/or a TVS tube. 4. The switching device according to claim 1, wherein the current limiting sub-circuit includes a third voltage dividing element. 5. The switching device according to claim 1, wherein the zero-crossing detection circuit includes: The first sub-detection circuit includes a first optical coupler. The first optical coupler includes a first light emitter and a first light receiver. Both ends of the first light emitter are connected to the input end of the decoupling circuit respectively. Electrically connected, the first end of the first light receiver is electrically connected to the control unit, and the second end of the first light receiver is grounded; The second sub-detection circuit includes a second optical coupler. The second optical coupler includes a second light emitter and a second light receiver. The first end of the second light emitter is connected to the second end of the second input loop. Two ends are electrically connected, the second end of the second light emitter is electrically connected to the output end of the decoupling circuit, the first end of the second light receiver is electrically connected to the control unit, the second light receiver The second end of the device is grounded. 6. The switching device according to any one of claims 1 to 5, characterized in that the control unit includes: A light-emitting device, the first end of the light-emitting device is grounded; A single-chip computer, which is electrically connected to the relay switch, the zero-crossing detection circuit, and the light-emitting device respectively. The single-chip computer is used to control the switching state of the relay switch according to the switch control instruction and the detection result. , and control the lighting state of the light-emitting device according to the lighting state of the relay switch. 7. The switching device according to any one of claims 1 to 5, characterized in that the switching device further includes: Power supply circuit, the input end of the power supply circuit is electrically connected to the output end of the decoupling circuit, the output end of the power supply circuit is electrically connected to the zero-crossing detection circuit and the control unit respectively, the power supply circuit is The decoupled alternating current is converted into direct current, and the voltage of the direct current is smaller than the voltage of the alternating current. 8. The switching device according to claim 7, characterized in that the power supply circuit includes a resistance-capacitance step-down sub-circuit, an isolated power supply, a non-isolated power supply or a low-voltage linear regulator. 9. An electrical appliance, characterized by comprising the switching device according to any one of claims 1 to 8.