Recoil current suppression method and system and range hood

Abstract

The invention relates to a recoil current suppression method and system and a smoke exhaust ventilator. The method comprises the steps that the bus voltage of a power supply bus is obtained; when the bus voltage is smaller than or equal to a preset voltage threshold value, the power supply bus is controlled to be disconnected from the IPM module, and a release channel of the IPM module is controlled to be connected; the release channel is used for releasing the recoil current generated by the fan, so that the recoil current generated by the range hood is effectively inhibited, the recoil current generated by the fan due to inertia or negative pressure continuously rotating cannot be transmitted to the power supply bus, the influence on other devices such as an auxiliary power supply at the rear end is avoided, the mistaken fault on the range hood is avoided, and the service life of the range hood is prolonged. And the reliability of the range hood is improved.

Description

Technical Field

[0001] This application relates to the technical field of range hoods, and particularly to a method and system for suppressing backflow current and a range hood. Background Art

[0002] A range hood, also known as an oil fume extractor, is an electrical appliance used to purify the kitchen environment. The range hood is installed above the kitchen stove and can quickly extract and discharge the oil fume and waste generated during the cooking process outdoors, thereby purifying the indoor air.

[0003] Currently, during the use of traditional range hoods, the fan of the range hood is driven by a drive board to operate the motor. In the case of shutdown and power-off, the fan will continue to rotate due to inertia or negative pressure, resulting in the generation of backflow current. The backflow current is likely to backflow to the bus bar end and affect other devices such as the auxiliary power supply at the rear end, causing the range hood to report a fault, resulting in abnormal working conditions of the range hood and affecting the user experience. Summary of the Invention

[0004] Based on this, a method and system for suppressing backflow current and a range hood are provided.

[0005] In a first aspect, this application provides a method for suppressing backflow current, which is applied to a range hood. The range hood includes a fan, an IPM module, and a power supply bus bar. The fan is connected to the IPM module, and the IPM module is connected to the power supply bus bar. The method for suppressing backflow current includes the following steps:

[0006] Obtain the bus bar voltage of the power supply bus bar;

[0007] When the bus bar voltage is less than or equal to a preset voltage threshold, control the disconnection between the power supply bus bar and the IPM module, and control the release channel of the IPM module to conduct; the release channel is used to release the backflow current generated by the fan.

[0008] In one embodiment, the IPM module includes an upper switching tube group and a lower switching tube group. The fan is respectively connected to the upper switching tube group and the lower switching tube group. The step of controlling the release channel of the IPM module to conduct includes:

[0009] Transmit a first level signal to the upper switching tube group to disconnect the upper switching tube group;

[0010] Transmit a second level signal to the lower switching tube group to conduct the lower switching tube group, so that the backflow current generated by the fan is released through the lower switching tube group.

[0011] In one embodiment, before the step of obtaining the bus bar voltage of the power supply bus bar includes:

[0012] When the range hood is in the shutdown state or the power-off state, detect the bus bar voltage of the power supply bus bar.

[0013] In one embodiment, after the step of obtaining the bus voltage of the power supply bus, the following steps are included:

[0014] When the bus voltage is greater than the preset voltage threshold, maintain the conduction between the power supply bus and the IPM module.

[0015] In a second aspect, the present application provides a backrush current suppression system, including a control chip and a switch control circuit; the control chip is respectively connected to the IPM module and the switch control circuit, the IPM module is used to connect the power supply bus and the fan, and the switch control circuit is used to conduct or disconnect the connection between the power supply bus and the IPM module;

[0016] The control chip is used to execute the steps of the backrush current suppression method as described in any one of the above.

[0017] In one embodiment, the switch control circuit includes a relay module and a switch module;

[0018] The switch module is connected between the relay module and the control chip, and the relay module is connected between the power supply bus and the IPM module.

[0019] In one embodiment, the relay module includes a relay and a first diode; the switch module includes a switch transistor, a first resistor, a second resistor, a third resistor, and a first capacitor;

[0020] The base of the switch transistor is respectively connected to the first end of the first resistor and the first end of the second resistor, the emitter of the switch transistor is connected to the first end of the third resistor, and the collector of the switch transistor is respectively connected to the anode of the first diode and the control end of the relay; the second end of the first resistor is connected to the control chip, the second end of the second resistor is connected to the second end of the third resistor, the second end of the third resistor is connected to the signal ground, the positive electrode of the first capacitor is connected to the second end of the first resistor, and the negative electrode of the first capacitor is connected to the second end of the second resistor;

[0021] The power supply terminal of the relay is respectively connected to the cathode of the first diode and the first power supply, the common terminal of the relay is connected to the IPM module, and the load terminal of the relay is connected to the power supply bus.

[0022] In one embodiment, the switch control circuit further includes an isolation module;

[0023] The isolation module is connected between the control chip and the switch module.

[0024] In one embodiment, the isolation module includes an optocoupler, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, and a second capacitor;

[0025] The first input terminal of the optocoupler is connected to the first end of the fourth resistor. The second input terminal of the optocoupler is respectively connected to the first end of the fifth resistor and the positive electrode of the second capacitor. The first output terminal of the optocoupler is respectively connected to the first end of the sixth resistor and the first end of the seventh resistor. The second output terminal of the optocoupler is connected to the signal ground;

[0026] The second end of the fourth resistor is connected to the power supply pin of the control chip. The second end of the fifth resistor is connected to the signal pin of the control chip. The negative electrode of the second capacitor is connected to the power ground. The second end of the sixth resistor is connected to the second power supply. The second end of the seventh resistor is connected to the switch module.

[0027] In a third aspect, the present application provides an extractor hood, including a hood body and a backrush current suppression system as described in any one of the above; the backrush current suppression system is arranged on the hood body.

[0028] One of the above technical solutions has the following advantages and beneficial effects:

[0029] In the above backrush current suppression method, when applied to an extractor hood, the extractor hood includes a fan, an IPM module, and a power supply bus. The fan is connected to the IPM module, and the IPM module is connected to the power supply bus; by obtaining the bus voltage of the power supply bus; when the bus voltage is less than or equal to a preset voltage threshold, controlling the disconnection of the power supply bus and the IPM module, and controlling the conduction of the release channel of the IPM module; the release channel is used to release the backrush current generated by the fan, so as to effectively suppress the backrush current generated by the extractor hood. The present application processes the obtained bus voltage to judge whether the extractor hood is powered off. If the bus voltage is less than or equal to the preset voltage threshold, it is determined that the extractor hood is powered off, and then the power supply bus and the IPM module are controlled to be disconnected, so that the backrush current generated by the fan due to inertia or negative pressure continuing to rotate cannot be transmitted to the power supply bus; at the same time, by conducting the release channel of the IPM module, the backrush current generated by the fan is released, avoiding affecting other devices such as the auxiliary power supply at the back end, avoiding false fault reports of the hood, and improving the reliability of the extractor hood. Description of the Drawings

[0030] Figure 1 It is a schematic diagram of the application scenario of the backrush current suppression method in the embodiment of the present application;

[0031] Figure 2 It is a schematic flowchart of the backrush current suppression method in the embodiment of the present application;

[0032] Figure 3 It is a schematic flowchart of the step of controlling the conduction of the release channel in the embodiment of the present application;

[0033] Figure 4 It is a first structural schematic diagram of the backrush current suppression system in the embodiment of the present application;

[0034] Figure 5 It is the second structural schematic diagram of the recoil current suppression system in the embodiment of the present application;

[0035] Figure 6 It is the circuit schematic diagram of the recoil current suppression system in the embodiment of the present application. Detailed implementation manners

[0036] In order to enable those skilled in the art to better understand the solution of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

[0037] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and do not necessarily need to describe a specific order or sequence. It should be understood that such used data can be interchanged under appropriate circumstances for the embodiments of the present application described herein. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device comprising a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0038] In addition, the meaning of the term "plurality" should be two or more.

[0039] It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments can be combined with each other. The present application will be described in detail below with reference to the drawings and in conjunction with the embodiments.

[0040] The recoil current suppression method provided by the present application can be applied to, for example Figure 1In the application environment shown. Among them, the processing device may include a processor 102 and a memory 104. The memory 104 can be used to store data such as bus voltage and preset voltage threshold. The processor 102 can be used to obtain the bus voltage of the power supply bus; when the bus voltage is less than or equal to the preset voltage threshold, control the disconnection of the power supply bus from the IPM (Intelligent Power Module) module, and control the conduction of the release channel of the IPM module; the release channel is used to release the backrush current generated by the fan. The processing device may also include a display 106, and the display 106 can display data such as bus voltage and preset voltage threshold through a graphical interface. Exemplarily, the processing device can be the control circuit board of a range hood, and the processing device is arranged on the range hood. The range hood is provided with a fan, an IPM module and a power supply bus. The fan is connected to the IPM module, the IPM module is connected to the power supply bus, the processor is respectively connected to the IPM module and the power supply bus, the power supply bus is used to supply power to the IPM module, and the IPM module is used to drive the fan to rotate. For example, the processor transmits a driving signal to the IPM, and alternately drives the upper and lower tubes of the IPM module to conduct through the driving signal, changes the rotor current flow direction of the fan, and further drives the motor to rotate.

[0041] In one embodiment, as Figure 2 shown, a method for suppressing backrush current is provided. Taking the processor 102 in Figure 1 as an example, the method includes the following steps:

[0042] Step S210, obtain the bus voltage of the power supply bus.

[0043] Among them, the power supply bus is used to connect to the commercial power. For example, the voltage of the power supply bus can be 220V. By sampling the voltage of the power supply bus, the bus voltage corresponding to the power supply bus can be obtained.

[0044] For example, the voltage of the power supply bus can be sampled based on a preset period; or, the voltage of the power supply bus can be sampled in real time after the range hood is powered off.

[0045] Step S220, when the bus voltage is less than or equal to the preset voltage threshold, control the disconnection of the power supply bus from the IPM module, and control the conduction of the release channel of the IPM module; the release channel is used to release the backrush current generated by the fan.

[0046] Compare the obtained bus voltage with the preset voltage threshold, and according to the comparison result, when the bus voltage is less than or equal to the preset voltage threshold, it is further determined that the range hood has performed a power-off operation. Exemplarily, the bus voltage can be the voltage difference within a unit time, then the preset voltage threshold can be the voltage drop threshold, and further, it can be determined whether the range hood has performed a power-off operation through the voltage drop threshold within a unit time.

[0047] When the bus voltage is less than or equal to the preset voltage threshold, the connection between the power supply bus and the IPM module is disconnected, so that the power supply bus and the IPM module are powered off. Thus, the backrush current generated due to inertia or negative pressure after the fan is powered off cannot be transmitted to the power supply bus through the IPM module; at the same time, by turning on the release channel of the IPM module, the backrush current generated by the fan can be released through the release channel of the IPM module. For example, the backrush current generated by the fan can be released to the ground through the release channel of the IPM module, thereby preventing the backrush current from flowing back to the power supply bus through the IPM module, avoiding affecting other devices such as the auxiliary power supply at the back end, making the auxiliary power supply not supply power, and keeping the state of the range hood unchanged, so as to prevent the influence of the backrush current on the fault and the board state.

[0048] In the above embodiment, it is applied to a range hood, which includes a fan, an IPM module and a power supply bus. The fan is connected to the IPM module, and the IPM module is connected to the power supply bus; by obtaining the bus voltage of the power supply bus; when the bus voltage is less than or equal to the preset voltage threshold, controlling the disconnection between the power supply bus and the IPM module, and controlling the release channel of the IPM module to be turned on; the release channel is used to release the backrush current generated by the fan, so as to effectively suppress the backrush current generated by the range hood. In this application, by processing the obtained bus voltage, it is judged whether the range hood is powered off. If the bus voltage is less than or equal to the preset voltage threshold, it is determined that the range hood is powered off, and then the connection between the power supply bus and the IPM module is controlled to be disconnected, so that the backrush current generated by the fan due to inertia or negative pressure continuing to rotate cannot be transmitted to the power supply bus; at the same time, by turning on the release channel of the IPM module, the backrush current generated by the fan is released, avoiding affecting other devices such as the auxiliary power supply at the back end, avoiding the range hood reporting false faults, and improving the reliability of the range hood.

[0049] In one embodiment, the IPM module includes an upper switch tube group and a lower switch tube group, and the fan is respectively connected to the upper switch tube group and the lower switch tube group.

[0050] For example, the upper switch tube group may include 3 upper switch tubes, the lower switch tube group may include 3 lower switch tubes, and the upper switch tubes and the lower switch tubes may be MOS tubes. The processor can transmit drive signals to the upper switch tube group and the lower switch tube group, and then the drive signals alternately drive the upper switch tube group and the lower switch tube group to conduct, so as to drive the fan to rotate. It should be noted that the fan includes an impeller and a motor, and the motor is used to drive the impeller to rotate, and the motor is respectively connected to the upper switch tube group and the lower switch tube group.

[0051] As Figure 3 shown, the steps of controlling the release channel of the IPM module to conduct include:

[0052] Step S310: Transmit a first level signal to the upper switch tube group to turn off the upper switch tube group.

[0053] Among them, the first level signal can be a low level signal.

[0054] For example, when the bus voltage is less than or equal to the preset voltage threshold, control the disconnection between the power supply bus and the IPM module. Then, when the fan is powered off, the backflow current generated due to inertia or negative pressure cannot be transmitted to the power supply bus through the IPM module; at the same time, transmit the first level signal to each upper switch tube in the upper switch tube group, and then each upper switch tube is turned off based on the first level signal.

[0055] Step S320: Transmit a second level signal to the lower switch tube group to turn on the lower switch tube group, so that the backflow current generated by the fan is released through the lower switch tube group.

[0056] Among them, the second level signal can be a high level signal.

[0057] For example, when the bus voltage is less than or equal to the preset voltage threshold, transmit the first level signal to the upper switch tube group, and at the same time transmit the second level signal to each lower switch tube in the lower switch tube group. Then, each lower switch tube is turned on based on the second level signal, and then the release channel of the IPM module is turned on, so that the backflow current generated by the fan can be released to the ground through the release channel of the IPM module. Thus, it is avoided that the backflow current rushes back to the power supply bus through the IPM module, which affects other devices such as the auxiliary power supply at the back end, causing the auxiliary power supply not to supply power and the state of the range hood to remain unchanged, realizing the prevention of the impact of the backflow current on the fault and the board state. For example, it is avoided that the backflow current causes the LED or the button light to flash, and it is also avoided that the backflow current causes the motor state to cause the reporting of the fault light phenomenon, etc., improving the reliability of the range hood.

[0058] In one embodiment, before the step of obtaining the bus voltage of the power supply bus, it includes:

[0059] When the range hood is in the shutdown state or the power-off state, detect the bus voltage of the power supply bus.

[0060] Among them, the range hood being in the shutdown state means that the range hood is not powered on; the range hood being in the power-off state means that the range hood is powered on but suddenly powered off and stops working.

[0061] When the range hood is in the shutdown state, the range hood is easily affected by negative pressure, causing the fan to rotate, and then the fan generates a backrush current. By detecting the bus voltage of the power supply bus when the range hood is in the shutdown state, if the detected bus voltage is less than or equal to the preset voltage threshold, the power supply bus is controlled to be disconnected from the IPM module, and the release channel of the PM module is turned on. Then, when the fan generates a backrush current due to negative pressure, the backrush current cannot be transmitted to the power supply bus, but is released to the ground through the release channel of the IPM module, avoiding affecting other devices such as the auxiliary power supply at the back end, preventing the range hood from reporting false faults, and improving the reliability of the range hood.

[0062] When the range hood is in the power-off state, the fan is easily affected by inertia and continues to rotate, and then the fan generates a backrush current. By detecting the bus voltage of the power supply bus when the range hood is in the power-off state, if the detected bus voltage is less than or equal to the preset voltage threshold, the power supply bus is controlled to be disconnected from the IPM module, and the release channel of the PM module is turned on. Then, when the fan generates a backrush current due to inertial rotation, the backrush current cannot be transmitted to the power supply bus, but is released to the ground through the release channel of the IPM module, avoiding affecting other devices such as the auxiliary power supply at the back end, preventing the range hood from reporting false faults, and improving the reliability of the range hood.

[0063] In one embodiment, after the step of obtaining the bus voltage of the power supply bus, it includes:

[0064] When the bus voltage is greater than the preset voltage threshold, maintain the conduction between the power supply bus and the IPM module.

[0065] Among them, the preset voltage threshold can be, but is not limited to, 214V.

[0066] By monitoring the bus voltage, if the bus voltage is greater than the preset voltage threshold, it is determined that the range hood is in the normal working state, and then the conduction between the power supply bus and the IPM module is maintained to ensure that the range hood can work normally.

[0067] It should be understood that although Figures 2 to 3 the steps in the flowchart of Figures 2 to 3At least some of the steps may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily executed and completed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed alternately or in turn with at least some of the other steps or sub-steps or stages of the other steps.

[0068] In one embodiment, the present application provides a backrush current suppression device, including:

[0069] A voltage acquisition unit for acquiring the bus voltage of the power supply bus.

[0070] A current suppression unit for controlling the disconnection of the power supply bus from the IPM module and the conduction of the release channel of the IPM module when the bus voltage is less than or equal to a preset voltage threshold; the release channel is used to release the backrush current generated by the fan.

[0071] For the specific limitations of the backrush current suppression device, reference can be made to the limitations of the backrush current suppression method in the above text, which will not be elaborated here. Each module in the above backrush current suppression device can be implemented in whole or in part by software, hardware, and their combination. The above modules can be embedded in the processor in the backrush current suppression system in hardware form or independent of it, or stored in the memory in the backrush current suppression system in software form, so as to facilitate the processor to call and execute the operations corresponding to the above modules.

[0072] In one embodiment, as Figure 4 shown, a backrush current suppression system is further provided, including a control chip 410 and a switch control circuit 420; the control chip 410 is respectively connected to the IPM module 430 and the switch control circuit 420, the IPM module 430 is used to connect the power supply bus and the fan 440, and the switch control circuit 420 is used to conduct or disconnect the connection between the power supply bus and the IPM module 430; the control chip 410 is used to execute the steps of the backrush current suppression method as described in any one of the above.

[0073] Among them, the control chip 410 can be used to transmit driving signals to the IPM module 430, thereby driving the IPM module 430 to work, so that the IPM module 430 controls the rotation of the fan 440. Exemplarily, the control chip 410 can also be used to drive the upper switching tube group of the IPM module 430 to turn off and the lower switching tube group to turn on, so that the recoil current can be released to the ground through the lower switching tube group of the IPM module 430. The control chip 410 is also used to drive the on / off of the switch control circuit 420, thereby connecting or disconnecting the power supply bus and the IPM module 430 through the switch control circuit 420. The IPM module 430 has an upper switching tube group and a lower switching tube group. When the upper switching tube group is turned off and the lower switching tube group is turned on, the release channel of the IPM module 430 is turned on. The power supply bus is used to supply power to the IPM module 430 and can be used to connect to the commercial power. The fan 440 has a motor and an impeller, and the impeller is arranged on the motor.

[0074] Based on the connection between the fan 440 and the IPM module 430, and the IPM module 430 is connected to the power supply bus through the switch control circuit 420. Then, when the range hood is in the shutdown state, the control chip 410 can control the disconnection of the power bus and the IPM module 430, and control the release channel of the IPM module 430 to be turned on. If the fan 440 rotates due to negative pressure, the generated recoil current can be released to the ground through the release channel of the IPM module 430; when the range hood is in the power-off state, the control chip 410 can control the disconnection of the power bus and the IPM module 430, and control the release channel of the IPM module 430 to be turned on. If the fan 440 rotates due to inertia, the generated recoil current can be released to the ground through the release channel of the IPM module 430.

[0075] In the above embodiment, the control chip 410 processes the obtained bus voltage to determine whether the range hood is powered off. If the bus voltage is less than or equal to the preset voltage threshold, it is determined that the range hood is powered off. Then, the power supply bus and the IPM module 430 are disconnected through the switch control circuit 420, so that the recoil current generated by the fan 440 continuing to rotate due to inertia or negative pressure cannot be transmitted to the power supply bus; at the same time, by turning on the release channel of the IPM module 430, the recoil current generated by the fan 440 is released, avoiding affecting other devices such as the auxiliary power supply at the back end, avoiding the range hood reporting false faults, and improving the reliability of the range hood.

[0076] In one embodiment, as Figure 5 shown, the switch control circuit 420 includes a relay module 422 and a switch module 424; the switch module 424 is connected between the relay module 422 and the control chip 410, and the relay module 422 is connected between the power supply bus and the IPM module 430.

[0077] Among them, the relay module 422 is used to disconnect or conduct the connection between the power supply bus and the IPM module 430.

[0078] Based on the fact that the switch module 424 is connected between the relay module 422 and the control chip 410, and the relay module 422 is connected between the power supply bus and the IPM module 430. Furthermore, when the bus voltage is less than or equal to the preset voltage threshold, the control chip 410 controls the switch module 424 to conduct, and the relay module 422 is powered on and works through the conduction of the switch module 424, so that the relay module 422 disconnects the connection between the power supply bus and the IPM module 430. Thus, the backrush current generated by the fan 440 continuing to rotate due to inertia or negative pressure cannot be transmitted to the power supply bus; at the same time, the control chip 410 controls the release channel of the IPM module 430 to conduct, so as to release the backrush current generated by the fan 440 through the release channel, avoid affecting other devices such as the auxiliary power supply at the back end, avoid the smoke machine reporting false faults, and improve the reliability of the range hood.

[0079] When the bus voltage is greater than the preset voltage threshold, the control chip 410 controls the switch module 424 to turn off. Furthermore, the disconnection of the switch module 424 causes the relay module 422 to disconnect, and the connection between the power supply bus and the IPM module 430 is conducted, so that the power supply bus normally supplies power to the IPM module 430, realizing the normal operation of the range hood.

[0080] In one example, as Figure 6 shown, the relay module includes a relay T1 and a first diode D1; the switch module includes a switching transistor Q1, a first resistor R1, a second resistor R2, a third resistor R3 and a first capacitor C1; the base of the switching transistor Q1 is respectively connected to the first end of the first resistor R1 and the first end of the second resistor R2, the emitter of the switching transistor Q1 is connected to the first end of the third resistor R3, and the collector of the switching transistor Q1 is respectively connected to the anode of the first diode D1 and the control terminal of the relay T1; the second end of the first resistor R1 is connected to the control chip, the second end of the second resistor R2 is connected to the second end of the third resistor R3, the second end of the third resistor R3 is connected to the signal ground, the positive electrode of the first capacitor C1 is connected to the second end of the first resistor R1, and the negative electrode of the first capacitor C1 is connected to the second end of the second resistor R2; the power supply terminal of the relay T1 is respectively connected to the cathode of the first diode D1 and the first power supply, the common terminal of the relay T1 is connected to the IPM module, and the load terminal of the relay T1 is connected to the power supply bus HV.

[0081] For example, when the bus voltage is less than or equal to a preset voltage threshold, the control chip first transmits a high-level signal through the switching module. Then, the switching transistor Q1 conducts according to the high-level signal, enabling the relay T1 to be powered on and work. Subsequently, the connection between the power supply bus HV and the IPM module is disconnected. As a result, the backrush current generated when the fan continues to rotate due to inertia or negative pressure cannot be transmitted to the power supply bus HV, preventing impacts on other devices such as the auxiliary power supply at the back end, avoiding false fault reports of the range hood, and improving the reliability of the range hood.

[0082] In one embodiment, as Figure 5 shown, the switch control circuit 420 further includes an isolation module 426; the isolation module 426 is connected between the control chip 410 and the switching module 424.

[0083] Among them, the isolation module 426 can be used to isolate strong electrical signals and weak electrical signals, thereby eliminating signal interference and improving the reliability and stability of the backrush current control.

[0084] Exemplarily, as Figure 6 shown, the isolation module includes an optocoupler OC1, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, and a second capacitor C2; the first input terminal of the optocoupler OC1 is connected to the first end of the fourth resistor R4, the second input terminal of the optocoupler OC1 is respectively connected to the first end of the fifth resistor R5 and the positive electrode of the second capacitor C2, the first output terminal of the optocoupler OC1 is respectively connected to the first end of the sixth resistor R6 and the first end of the seventh resistor R7, the second output terminal of the optocoupler OC1 is connected to the signal ground; the second end of the fourth resistor R4 is connected to the power supply pin of the control chip, the second end of the fifth resistor R5 is connected to the signal pin of the control chip, the negative electrode of the second capacitor C2 is connected to the power ground, the second end of the sixth resistor R6 is connected to the second power supply, and the second end of the seventh resistor R7 is connected to the switching module.

[0085] For example, based on the isolation module being connected between the control chip and the switching module, when the bus voltage is less than or equal to a preset voltage threshold, the control chip outputs a control signal. The control signal is transmitted to the switching module after passing through the isolation module, and then the switching module is turned on to power on the relay module, causing the relay module to disconnect the connection between the power supply bus and the IPM module. As a result, the backrush current generated when the fan continues to rotate due to inertia or negative pressure cannot be transmitted to the power supply bus, preventing impacts on other devices such as the auxiliary power supply at the back end, avoiding false fault reports of the range hood, and improving the reliability of the range hood.

[0086] In one embodiment, a range hood is further provided, including a range hood body and a backrush current suppression system as described in any one of the above; the backrush current suppression system is provided in the range hood body.

[0087] The recoil current suppression system is provided on the main body of the range hood. The main body of the range hood is provided with a fan, an IPM module, and a power supply busbar. The recoil current suppression system is respectively connected to the IPM module and the power supply busbar. The fan is connected to the IPM module, and the IPM module is connected to the power supply busbar. By obtaining the bus voltage of the power supply busbar, when the bus voltage is less than or equal to the preset voltage threshold, the connection between the power supply busbar and the IPM module is controlled to be disconnected, and the release channel of the IPM module is controlled to be turned on. The release channel is used to release the recoil current generated by the fan, so as to effectively suppress the recoil current generated by the range hood.

[0088] In the above embodiment, the recoil current suppression system processes the obtained bus voltage to determine whether the range hood is powered off. If the bus voltage is less than or equal to the preset voltage threshold, it is determined that the range hood is powered off, and then the connection between the power supply busbar and the IPM module is controlled to be disconnected, so that the recoil current generated by the fan due to inertia or negative pressure continuing to rotate cannot be transmitted to the power supply busbar. At the same time, by turning on the release channel of the IPM module, the recoil current generated by the fan is released, avoiding affecting other devices such as the auxiliary power supply at the back end, avoiding false fault reports of the range hood, and improving the reliability of the range hood.

[0089] In one embodiment, the present application provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of any one of the above recoil current suppression methods are implemented.

[0090] For example, when the computer program is executed by a processor, the steps of the following recoil current suppression method are implemented:

[0091] Obtain the bus voltage of the power supply busbar; when the bus voltage is less than or equal to the preset voltage threshold, control the disconnection between the power supply busbar and the IPM module, and control the release channel of the IPM module to be turned on. The release channel is used to release the recoil current generated by the fan, so as to effectively suppress the recoil current generated by the range hood.

[0092] Those of ordinary skill in the art can understand that all or part of the processes in the methods of the above embodiments can be completed by instructing relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above division operation methods. Among them, any reference to a memory, storage, database, or other medium used in the various embodiments provided in the present application can include non-volatile and / or volatile memories. Non-volatile memories can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memories can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), Rambus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and Rambus dynamic RAM (RDRAM), etc.

[0093] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0094] The above-described embodiments merely represent several implementation manners of the present application. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the patent application. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can still be made, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A method for suppressing a kickback current, characterized in that: Applied to a range hood, the range hood comprises a fan, an IPM module and a power supply bus, the fan is connected to the IPM module, and the IPM module is connected to the power supply bus; the backwash current suppression method comprises the following steps: Obtaining a bus voltage of the power supply bus; When the bus voltage is less than or equal to a preset voltage threshold, the power supply bus is controlled to be disconnected from the IPM module, and the release channel of the IPM module is controlled to be turned on; the release channel is used to release the recoil current generated by the fan.

2. The method for suppressing the kickback current according to claim 1, characterized in that: The IPM module comprises an upper switch tube group and a lower switch tube group, and the fan is connected to the upper switch tube group and the lower switch tube group respectively; The step of controlling the release channel of the IPM module to be turned on comprises: Transmitting a first level signal to the upper switch tube group to disconnect the upper switch tube group; A second level signal is transmitted to the lower switch tube group to turn on the lower switch tube group, so that the recoil current generated by the fan is released through the lower switch tube group.

3. The method for suppressing a kickback current according to claim 1, characterized in that: The step of obtaining the bus voltage of the power supply bus includes: When the range hood is in a shutdown state or a power-off state, the bus voltage of the power supply bus is detected.

4. The method for suppressing a kickback current according to any one of claims 1 to 3, characterized in that: The step of obtaining the bus voltage of the power supply bus comprises: When the bus voltage is greater than a preset voltage threshold, the power supply bus and the IPM module are maintained in conduction.

5. A kickback current suppression system, characterized in that: It includes a control chip and a switch control circuit; the control chip is connected to the IPM module and the switch control circuit respectively, the IPM module is used to connect the power supply bus and the fan, and the switch control circuit is used to turn on or off the connection between the power supply bus and the IPM module; The control chip is used to execute the steps of the kickback current suppression method as described in any one of claims 1 to 4.

6. The kickback current suppression system according to claim 5, characterized in that: The switch control circuit includes a relay module and a switch module; The switch module is connected between the relay module and the control chip, and the relay module is connected between the power supply bus and the IPM module.

7. The kickback current suppression system according to claim 6, characterized in that: The relay module includes a relay and a first diode; the switch module includes a switch tube, a first resistor, a second resistor, a third resistor and a first capacitor; The base of the switch tube is respectively connected to the first end of the first resistor and the first end of the second resistor, the emitter of the switch tube is connected to the first end of the third resistor, and the collector of the switch tube is respectively connected to the anode of the first diode and the control end of the relay; the second end of the first resistor is connected to the control chip, the second end of the second resistor is connected to the second end of the third resistor, the second end of the third resistor is connected to the signal ground, the positive electrode of the first capacitor is connected to the second end of the first resistor, and the negative electrode of the first capacitor is connected to the second end of the second resistor; The power supply end of the relay is respectively connected to the cathode of the first diode and the first power supply, the common end of the relay is connected to the IPM module, and the load end of the relay is connected to the power supply bus.

8. The kickback current suppression system according to claim 6, characterized in that: The switch control circuit also includes an isolation module; The isolation module is connected between the control chip and the switch module.

9. The kickback current suppression system according to claim 8, characterized in that: The isolation module includes a photoelectric coupler, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor and a second capacitor; The first input end of the photoelectric coupler is connected to the first end of the fourth resistor, the second input end of the photoelectric coupler is respectively connected to the first end of the fifth resistor and the positive electrode of the second capacitor, the first output end of the photoelectric coupler is respectively connected to the first end of the sixth resistor and the first end of the seventh resistor, and the second output end of the photoelectric coupler is connected to the signal ground; The second end of the fourth resistor is connected to the power supply pin of the control chip, the second end of the fifth resistor is connected to the signal pin of the control chip, the negative electrode of the second capacitor is connected to the power ground, the second end of the sixth resistor is connected to the second power supply, and the second end of the seventh resistor is connected to the switch module.

10. A range hood, characterized in that: It comprises a range hood body and a recoil current suppression system as described in any one of claims 5 to 9; the recoil current suppression system is arranged on the range hood body.

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