Self-protection fan control device and refrigerator

Abstract

The invention relates to a self-protection fan control device and a refrigerator, the device is used for the refrigerator, and the device comprises a hardware control module, a power module and a software control module; the software control module is connected with the fan and the power supply module and is used for acquiring the real-time current of the fan and generating a corresponding fan control signal based on the real-time current and a preset protection threshold value; the power supply module is also connected with the hardware control module and is used for outputting a corresponding power supply driving signal under the action of the fan control signal so as to control the working state of the fan; the hardware control module is further connected with the fan and used for being disconnected under the condition that the current of the fan is larger than the action current of the hardware control module and being connected under the condition that the current of the fan is smaller than the action current of the hardware control module; the problem that a traditional software overcurrent protection mechanism is poor in reliability is solved, software and hardware are combined, dual current protection is provided for the refrigerator, and the protection reliability is improved.

Description

Technical Field

[0001] The present application relates to the technical field of refrigerators, and in particular to a self-protection fan control device and a refrigerator. Background Art

[0002] Modern refrigerators commonly use fans (such as freezer fans, refrigerator fans, or cooling fans) to forcefully circulate cold air or dissipate heat. This is crucial for cooling efficiency, temperature uniformity, and energy efficiency. However, over long-term operation, fans can experience abnormal overcurrent due to factors such as blade obstruction, bearing wear and aging, voltage fluctuations, control circuit failures, or extreme operating conditions (such as poor heat dissipation due to heavy dust accumulation in the condenser). Sustained overcurrent can not only damage the fan motor itself but also cause the drive circuit to overheat or even catch fire, posing a safety hazard and impacting the overall performance and lifespan of the refrigerator.

[0003] Existing refrigerator fan circuits usually use software control methods for overcurrent protection, so that the microcontroller (MCU) cuts off the driving power when the fan current exceeds a preset threshold.

[0004] However, the traditional software overcurrent protection mechanism has poor reliability. Due to the reduced accuracy of current sampling or the existence of instantaneous large currents with extremely short duration, the software cannot respond in time, thereby losing the current protection function and causing damage to structures such as fans. Summary of the Invention

[0005] In this embodiment, a self-protection fan control device and a refrigerator are provided to solve the problem of poor reliability of the traditional software overcurrent protection mechanism in the related art.

[0006] In a first aspect, a self-protection fan control device is provided in this embodiment. The device is used in a refrigerator and includes: a hardware control module, a power module, and a software control module;

[0007] The software control module is connected to the fan and the power module, and is used to collect the real-time current of the fan and generate a corresponding fan control signal based on the real-time current and a preset protection threshold;

[0008] The power supply module is also connected to the hardware control module and is used to output a corresponding power drive signal under the action of the fan control signal to control the working state of the fan;

[0009] The hardware control module is also connected to the fan, and is used to disconnect when the current of the fan is greater than the action current of the hardware control module, and to connect when the current of the fan is less than the action current of the hardware control module; the action current is greater than the protection threshold.

[0010] In some embodiments, generating a corresponding wind turbine control signal based on the real-time current and a preset protection threshold includes:

[0011] If the real-time current is greater than a preset first protection threshold and lasts for a preset detection time, a fan shutdown signal is output;

[0012] If the real-time current is less than the first protection threshold and greater than or equal to a preset second protection threshold, the duty cycle of the fan start signal is reduced until the real-time current is less than the second protection threshold.

[0013] In some embodiments, the software control module is further configured to perform a restart determination after the hardware control module is triggered, and output a fan start signal if the restart determination meets the requirements and reaches a preset number of consecutive times;

[0014] The restart determination meeting the requirements includes: after a preset recovery time, the real-time current collected is greater than a preset third protection threshold.

[0015] In some embodiments, the software control module is further configured to diagnose and predict faults of the fan based on the real-time current, and generate a fan shutdown signal based on the diagnosis and prediction results.

[0016] In some of the embodiments, the device further comprises a temperature sensor connected to the software control module, the temperature sensor being used to collect the ambient temperature of the self-protection fan control device;

[0017] The software control module is further configured to increase the set value of the protection threshold according to a decrease in the ambient temperature.

[0018] In some of the embodiments, the power supply module includes: a switching circuit and a filtering and rectifying circuit;

[0019] The switching circuit is connected to the power supply, the filtering and rectifying circuit and the software control module, and is used to output an initial driving signal based on the received fan control signal;

[0020] The filtering and rectifying circuit is connected to the hardware control module and is used to rectify and filter the initial driving signal to obtain a power driving signal.

[0021] In some embodiments, the switch circuit includes: a first switch unit and a second switch unit;

[0022] The first switch unit is connected to the software control module and the second switch unit, and is configured to be turned on or off under the control of the software control module;

[0023] The second switch unit is further connected to the power supply and the filter rectifier circuit, and is configured to be turned on when the first switch unit is turned on, and turned off when the first switch unit is turned off, so as to generate the corresponding initial drive signal.

[0024] In some embodiments, the first switch unit includes a first transistor, a first resistor, a second resistor, a first diode, and a second diode; the second switch unit includes a second transistor, a third resistor, and a fourth resistor;

[0025] The first end of the first transistor is connected to a power supply; the first end of the first transistor is also connected to the second end of the first transistor via the first resistor; the second end of the first transistor is connected to the first end of the second transistor via the second resistor, and the third end of the first transistor is connected to the filter rectifier circuit; the third end of the first transistor is also connected to the anode of the first diode and the cathode of the second diode respectively; the cathode of the first diode is connected to the power supply; and the anode of the second diode is grounded.

[0026] The second end of the second transistor is connected to the software control module through the third resistor; the second end of the second transistor is also grounded through the fourth resistor; and the third end of the second transistor is grounded.

[0027] In some embodiments, the filtering and rectifying circuit includes: an inductor, a first capacitor, and a fifth resistor;

[0028] One end of the inductor is connected to the switch circuit, and the other end of the inductor is connected to the hardware control module;

[0029] The other end of the inductor is also connected to the positive electrode of the first capacitor and one end of the fifth resistor respectively; the negative electrode of the first capacitor is grounded, and the other end of the fifth resistor is grounded.

[0030] In a second aspect, a refrigerator is provided in this embodiment, comprising a fan and the self-protection fan control device described in any one of the first aspects.

[0031] Compared with the related art, the self-protection fan control device and refrigerator provided in this embodiment are used in the refrigerator through the device, including: a hardware control module, a power supply module, and a software control module; the software control module is connected to the fan and the power supply module, and is used to collect the real-time current of the fan, and generate a corresponding fan control signal based on the real-time current and a preset protection threshold; the power supply module is also connected to the hardware control module, and is used to output a corresponding power drive signal under the action of the fan control signal to control the working state of the fan; the hardware control module is also connected to the fan, and is used to disconnect when the current of the fan is greater than the action current of the hardware control module, and to turn on when the current of the fan is less than the action current of the hardware control module; the action current is greater than the protection threshold, which solves the problem of poor reliability of the traditional software overcurrent protection mechanism, combines software and hardware, provides dual current protection for the refrigerator, and improves the reliability of protection.

[0032] The details of one or more embodiments of the present application are set forth in the following drawings and description to make other features, objects, and advantages of the present application more readily apparent. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0034] Figure 1 This is a structural block diagram of a self-protection wind turbine control device in an embodiment of the present application;

[0035] Figure 2 This is a flow chart of the software control module executing the control method in the embodiment of the present application;

[0036] Figure 3 This is a structural block diagram of a self-protection wind turbine control device in another embodiment of the present application;

[0037] Figure 4 This is a structural block diagram of a self-protection wind turbine control device in a preferred embodiment of the present application;

[0038] Figure 5 Schematic diagram of the circuit structure of the self-protection fan control device in an embodiment of the present application.

[0039] Figure numerals: 100, self-protection fan control device; 110, hardware control module; 120, power supply module; 121, switching circuit; 122, filter rectifier circuit; 130, software control module; 140, temperature sensor; 200, fan. DETAILED DESCRIPTION

[0040] In order to more clearly understand the purpose, technical solutions and advantages of the present application, the present application is described and illustrated below in conjunction with the accompanying drawings and embodiments.

[0041] Unless otherwise defined, technical or scientific terms used in this application shall have the ordinary meanings as understood by persons of ordinary skill in the art to which this application belongs. The terms "a," "an," "the," "these," and similar expressions in this application do not denote limitations on quantity and may be singular or plural. The terms "comprise," "include," "have," and any variations thereof, as used in this application, are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or device comprising a series of steps or modules (units) is not limited to the listed steps or modules (units) but may include unlisted steps or modules (units) or other steps or modules (units) inherent to the process, method, product, or device. The terms "connected," "connected," "coupled," and similar expressions used in this application are not limited to physical or mechanical connections but may include electrical connections, whether direct or indirect. As used in this application, "plurality" means two or more. "And / or" describes an association between associated objects, indicating that three possible relationships exist. For example, "A and / or B" can mean: A exists alone; A and B exist simultaneously; or B exists alone. Generally, the character " / " indicates that the objects in the preceding and following relationship are in an "or" relationship. The terms "first", "second", "third", etc. involved in this application are only used to distinguish similar objects and do not represent a specific ordering of the objects.

[0042] In this embodiment, a self-protection fan control device 100 is provided, which is used in a refrigerator. Figure 1 is a structural block diagram of the self-protection wind turbine control device 100 in this embodiment, as shown in FIG. Figure 1 As shown, the device includes: a hardware control module 110 , a power module 120 and a software control module 130 .

[0043] The software control module 130 is connected to the fan 200 and the power module 120 , and is used to collect the real-time current of the fan 200 and generate a corresponding control signal for the fan 200 based on the real-time current and a preset protection threshold.

[0044] Specifically, the software control module 130 can be implemented by a sampling resistor and a microcontroller MCU, wherein one end of the sampling resistor is connected to the fan 200, and the other end of the sampling resistor is connected to the current detection I / O port of the MCU. The MCU calculates the real-time current based on the current data collected by the current detection I / O port, and outputs the corresponding fan 200 control signal at the power supply and speed regulation I / O port based on the real-time current, including a fan start signal and a fan stop signal.

[0045] The power module 120 is also connected to the hardware control module 110 and is used to output a corresponding power drive signal under the action of the fan 200 control signal to control the working state of the fan 200.

[0046] Specifically, the power module 120 connects the VDD power supply to the fan 200 via a switch circuit 121, which is controlled by the software control module 130. When the switch circuit 121 is on, the VDD power supply can power the fan 200 and regulate its speed. When the switch circuit 121 is off, the VDD power supply is disconnected from the fan 200. In situations such as when the fan 200 load experiences an overcurrent, a wiring short circuit occurs, or the fan 200 experiences a stall, the real-time current I_R collected by the software control module 130 will significantly increase. When this value exceeds a protection threshold, the software control module 130 will output a low-level signal, turning off the switch circuit 121 and disconnecting the VDD power supply. This will cause the fan 200 to cease operation, preventing damage to components within the circuit.

[0047] The hardware control module 110 is also connected to the fan 200, and is used to disconnect when the current of the fan 200 is greater than the operating current of the hardware control module 110, and to connect when the current of the fan 200 is less than the operating current of the hardware control module 110; the operating current is greater than the protection threshold.

[0048] Specifically, the hardware control module 110 is connected in series between the fan 200 and the power supply, enabling timely hardware-based current cutoff when necessary. Furthermore, the hardware control module 110 automatically resets after disconnection, eliminating the need to disassemble and replace a blown fuse. The hardware control module 110 can utilize a resettable fuse RF1. When the fan 200 is operating normally, the real-time current collected by the software control module 130 does not exceed the protection threshold. The software control module 130 outputs a high level, turning on the switch circuit 121. The VDD power supply flows through the resettable fuse RF1 to power the fan 200, ultimately connecting to the power ground via a sampling resistor. In situations such as a load overcurrent on the fan 200, a wiring short circuit in the fan 200, or a stall in the fan 200, the current Ia flowing through the resettable fuse RF1 will significantly increase. When Ia reaches the resettable fuse RF1's operating current, I_RF, the resettable fuse RF1 automatically disconnects the power circuit, halting the fan 200 and protecting the components in the circuit from damage. When there is no abnormality in the fan 200 or the connecting harness, Ia<I_RF, the resettable fuse RF1 automatically returns to the conducting state, and the fan 200 circuit can return to the normal working mode.

[0049] In this embodiment, the software control module 130 is connected to the fan 200 and the power module 120 to collect the real-time current of the fan 200, and generate a corresponding fan 200 control signal based on the real-time current and the preset protection threshold; the power module 120 is connected to the resettable fuse RF1 to output the corresponding power drive signal under the action of the fan 200 control signal to control the working state of the fan 200; the resettable fuse RF1 is connected to the fan 200 to disconnect when the current of the fan 200 is greater than the operating current of the resettable fuse RF1, and to turn on when the current of the fan 200 is less than the operating current of the resettable fuse RF1; the operating current is greater than the protection threshold, which solves the problem of poor reliability of the traditional software overcurrent protection mechanism, combines software and hardware, provides dual current protection for the refrigerator, and improves the reliability of protection.

[0050] In some of these embodiments, see Figure 2 Based on the real-time current and the preset protection threshold, a corresponding fan 200 control signal is generated, including: step S101, if the real-time current is greater than the preset first protection threshold and lasts for the preset detection time, a fan shutdown signal is output.

[0051] Specifically, the first protection threshold is preset to 2 times the rated current value I_FAN of fan 200, and the operating current I_RF can be preset to 3 times the rated current value I_FAN of fan 200 for 200ms. The detection time is preset to 200ms. When I_R ≥ 2I_FAN and the detection time lasts for more than 200ms, a fan shutdown signal is output to disconnect the VDD power supply of fan 200, at which point fan 200 will cease operation. The above preset data is for illustration only, and its value can be set according to specific usage and is not limited in this embodiment.

[0052] In this embodiment, the dual conditional restrictions of the first protection threshold and the detection time are used to avoid frequent false triggering of the software overcurrent protection, thereby preventing the normal operation of the wind turbine 200 from being affected.

[0053] In some of these embodiments, see Figure 2 , based on the real-time current and the preset protection threshold, generating a corresponding fan 200 control signal, also includes: step S102, if the real-time current is less than the first protection threshold and greater than or equal to the preset second protection threshold, then reducing the duty cycle of the fan start signal until the real-time current is less than the second protection threshold.

[0054] Specifically, when dust accumulation or foreign matter causes increased rotational resistance but does not completely stall, fan 200 must output greater torque to maintain speed, and the current typically rises to 1.5 to 2 times the rated value. Based on this, protection thresholds are set: the first protection threshold is preset to 2I_FAN, and the second protection threshold is preset to 1.5I_FAN. When the real-time current I_R ≥ 1.5I_FAN but I_R < 2I_FAN, the software control module 130 linearly reduces the PWM duty cycle (for example, by 5% every 0.1 second), reducing the speed of fan 200 and thus the current of fan 200.

[0055] In this embodiment, a hierarchical response mechanism is implemented: Level 1 protection (hardware rapid disconnection): When the operating current of the resettable fuse RF1 exceeds the first protection threshold, the resettable fuse RF1 quickly disconnects the circuit within 10ms when the operating current of the fan 200 increases to the operating current, preventing component burnout. Level 2 protection (software dynamic adjustment): The software control module 130 monitors the fan 200 current in real time. When the collected current is between the first and second protection thresholds, the duty cycle of the fan start signal is reduced, gradually reducing the current to a safe range. Hardware protection handles extreme faults (such as short circuits), while software protection handles mild anomalies (such as the initial stage of a stall), with clear division of labor.

[0056] In some of these embodiments, see Figure 2The software control module 130 is further configured to execute step S103, and perform a restart determination after the hardware control module 110 is triggered. If the restart determination meets the requirements and reaches a preset number of consecutive times, a fan start signal is output; wherein, the restart determination meets the requirements including: after a preset recovery time interval, the real-time current collected is greater than a preset third protection threshold.

[0057] Specifically, when the current Ia flowing through hardware control module 110 increases and reaches or exceeds the operating current I_RF of hardware control module 110, hardware control module 110 disconnects, indicating that hardware control module 110 is triggered. Typically, hardware control module 110 automatically reconnects after being triggered. In this case, software control module 130 can check the real-time current every 5 seconds. If the real-time current is detected to be less than 1.5I_FAN for 6 consecutive times (30 seconds), it automatically sends a high-level signal to restart fan 200.

[0058] In this embodiment, combined with software control, the wind turbine 200 is restarted with a delay to avoid frequent triggering of hardware protection due to instantaneous overcurrent, thereby extending the life of the fuse.

[0059] It should be noted that Figure 2 The steps shown in the flowchart can be executed in a computer system such as a set of computer-executable instructions. Although a logical order is shown in the flowchart, in some cases, the steps shown or described can be performed in an order different from that shown.

[0060] In some embodiments, the software control module 130 is further configured to diagnose and predict faults of the fan 200 based on the real-time current, and generate a fan shutdown signal based on the diagnosis and prediction results.

[0061] Specifically, the real-time current rise slope (di / dt) can be used to distinguish between a stalled rotor and a normal startup. During a normal startup, the current rises from 0 to 2I_FAN within 100ms and falls back to below 1.5I_FAN within 200ms. In a stalled rotor fault, the current rises to 3I_FAN within 100ms and persists for 200ms or longer without falling back. Protection is only triggered for a stalled rotor event, preventing false tripping during a normal startup.

[0062] Furthermore, the software control module 130 has a built-in fault code library, which can match the fault type according to the characteristics of the real-time current: Code E1: continuous high current (wiring harness short circuit); Code E2: periodic current fluctuation (fan 200 fault); Code E3: current drop (connector loose); thereby determining the fault type.

[0063] Furthermore, software control module 130 is used for predictive maintenance. This involves recording the daily peak starting current of wind turbine 200 and using a moving average algorithm to predict trends. If the peak current increases by more than 5% for three consecutive days, a "Maintenance Recommended" prompt is triggered. Fault codes and current data can also be sent to the cloud platform to generate maintenance reports.

[0064] In some of these embodiments, see Figure 3 The device further includes a temperature sensor 140 connected to the software control module 130, and the temperature sensor 140 is used to collect the ambient temperature of the self-protection fan control device 100. The software control module 130 is also used to increase the set value of the protection threshold according to the decrease in ambient temperature.

[0065] Specifically, refrigerators are often placed in low-temperature or high-humidity environments (such as cold storage rooms or winter kitchens), requiring fan 200 to maintain stable operation even under extreme conditions such as -20°C. The low temperature environment within the refrigerator can affect motor operation. For example, in low-temperature environments, the resistance of the refrigerator fan 200 motor winding decreases, and the instantaneous startup current may exceed the normal threshold (such as 2I_FAN), causing frequent triggering of software and hardware protections and affecting the stability of the refrigeration system. For another example, low temperatures can cause performance changes in circuit components (such as resistors and MOSFETs), reducing current sampling accuracy. Traditional fixed threshold designs are unable to adapt to dynamic environments. Traditional fixed thresholds are prone to triggering protection in low temperatures due to current fluctuations. Dynamic adjustment can reduce false tripping. Therefore, the built-in temperature sensor 140 reads the ambient temperature (T) in real time. When T ≤ 0°C, the first protection threshold is increased to 2.5I_FAN; when T > 0°C, the threshold is restored to the default value of 2I_FAN.

[0066] In some of these embodiments, see Figure 4 The power module 120 includes a switching circuit 121 and a filtering and rectifying circuit 122 .

[0067] The switch circuit 121 is connected to the power supply, the filter and rectifier circuit 122 and the software control module 130 , and is configured to output an initial drive signal based on the received control signal of the fan 200 .

[0068] The filtering and rectifying circuit 122 is connected to the hardware control module 110 and is used to rectify and filter the initial driving signal to obtain a power driving signal, thereby providing a stable operating current for the fan 200 .

[0069] In some embodiments, the switch circuit 121 includes a first switch unit and a second switch unit.

[0070] The first switch unit is connected to the software control module 130 and the second switch unit, and is configured to be turned on or off under the control of the software control module 130 .

[0071] The second switch unit is also connected to the power supply and the filter rectifier circuit 122, and is configured to be turned on when the first switch unit is turned on, and turned off when the first switch unit is turned off, so as to output a corresponding initial driving signal.

[0072] In some of these embodiments, see Figure 5 The first switch unit includes a first transistor Q1, a first resistor R1, a second resistor R2, a first diode D1 and a second diode D2; the second switch unit includes a second transistor Q2, a third resistor R3 and a fourth resistor R4.

[0073] The first end of the first transistor Q1 is connected to the power supply VDD; the first end of the first transistor Q1 is also connected to the second end of the first transistor Q1 through the first resistor R1; the second end of the first transistor Q1 is connected to the first end of the second transistor Q2 through the second resistor R2, and the third end of the first transistor Q1 is connected to the filtering and rectifying circuit 122; the third end of the first transistor Q1 is also connected to the anode of the first diode D1 and the cathode of the second diode D2 respectively; the cathode of the first diode D1 is connected to the power supply VDD; and the anode of the second diode D2 is grounded.

[0074] The second end of the second transistor Q2 is connected to the software control module 130 via the third resistor R3 ; the second end of the second transistor Q2 is also grounded via the fourth resistor R4 ; and the third end of the second transistor Q2 is grounded.

[0075] In some of these embodiments, see Figure 5 The filter and rectifier circuit 122 includes an inductor L1, a first capacitor EC1, and a fifth resistor R5. One end of the inductor L1 is connected to the switch circuit 121, and the other end of the inductor L1 is connected to the hardware control module 110. The other end of the inductor L1 is also connected to the positive electrode of the first capacitor EC1 and one end of the fifth resistor R5, respectively. The negative electrode of the first capacitor EC1 is grounded, and the other end of the fifth resistor R5 is grounded.

[0076] In some of these embodiments, see Figure 5 The software control module 130 includes a sixth resistor R6, a seventh resistor R7, a second capacitor C1, and a microcontroller MCU. One end of the sixth resistor R6 is connected to the wind turbine 200, and the other end of the sixth resistor R6 is grounded. One end of the sixth resistor R6 is also connected to one end of the seventh resistor R7, and the other end of the seventh resistor R7 is connected to the current detection port (current detection I / O) of the microcontroller MCU. The other end of the seventh resistor R7 is also connected to ground via the second capacitor C1. The sixth resistor R6 serves as a current sampling resistor connected in series between the wind turbine 200 and the MCU. The seventh resistor R7 and the second capacitor C1 provide current limiting and filtering functions.

[0077] In some of these embodiments, see Figure 5 Software control module 130 also includes an eighth resistor R8, a ninth resistor R9, and a third capacitor C2. Fan 200 is connected to power supply VCC via eighth resistor R8. Fan 200 is also connected to the speed detection port (speed detection I / O) of the microcontroller MCU via ninth resistor R9. The speed detection port is also connected to ground via third capacitor C2. During operation, fan 200 actively outputs speed feedback signals with varying duty cycles. After processing by resistors R8 and R9, these signals are provided to the MCU as a stable signal for speed calculation and real-time monitoring of the current speed.

[0078] In this embodiment, a refrigerator is provided. The refrigerator includes a fan 200 and the self-protection fan control device 100 in any of the above embodiments.

[0079] In this embodiment, the problem of poor reliability of the refrigerator overcurrent protection mechanism is solved. Software and hardware protection are combined to provide dual current protection for the refrigerator, thereby improving the reliability of the protection.

[0080] The present embodiment is described and illustrated below through preferred embodiments.

[0081] See also Figure 4 and Figure 5 The self-protection wind turbine control device 100 of this preferred embodiment includes: a hardware control module 110 , a power supply module 120 and a software control module 130 .

[0082] The software control module 130 includes a sixth resistor R6, a seventh resistor R7, a second capacitor C1, and a microcontroller MCU. The current detection I / O of the microcontroller MCU collects the real-time current I_R of the fan 200 through the sixth resistor R6. The seventh resistor R7 and the second capacitor C1 play a filtering and rectifying role when collecting the real-time current. The software control module 130 is also used to perform the following steps: if the real-time current I_R is greater than a preset first protection threshold and lasts for a preset detection time, then the power supply and speed control I / O outputs a fan shutdown signal; if the real-time current I_R is less than the first protection threshold and greater than or equal to a preset second protection threshold, then the duty cycle of the fan start signal output by the power supply and speed control I / O is reduced until the real-time current is less than the second protection threshold. After the hardware control module 110 is triggered, a restart determination is performed. If the restart determination meets the requirements and reaches a preset number of consecutive times, the fan start signal is output; wherein, the restart determination meeting the requirements includes: after a preset recovery time interval, the collected real-time current is greater than a preset third protection threshold. The fan 200 fault is diagnosed and predicted based on the real-time current, and a fan shutdown signal is generated based on the diagnosis and prediction results. The ambient temperature detected by the temperature sensor 140 is obtained, and the set value of the protection threshold is increased as the ambient temperature decreases.

[0083] The power supply and speed control I / O of the software control module 130 are connected to the power supply module 120. The power supply module 120 includes a switching circuit 121 and a filtering and rectifying circuit 122. The switching circuit 121 is connected to the power supply, filtering and rectifying circuit 122, and the software control module 130 and is configured to output an initial drive signal based on the received fan start signal. The filtering and rectifying circuit 122 is connected to the hardware control module 110 and is configured to rectify and filter the initial drive signal to generate a power drive signal, thereby providing a stable operating current for the fan 200.

[0084] The switch circuit 121 includes a first transistor Q1, a first resistor R1, a second resistor R2, a first diode D1, a second diode D2, a second transistor Q2, a third resistor R3, and a fourth resistor R4. The filter rectifier circuit 122 includes an inductor L1, a first capacitor EC1, and a fifth resistor R5.

[0085] The first end of the first transistor Q1 is connected to the power supply VDD; the first end of the first transistor Q1 is also connected to the second end of the first transistor Q1 via a first resistor R1; the second end of the first transistor Q1 is connected to the first end of the second transistor Q2 via a second resistor R2; the third end of the first transistor Q1 is connected to one end of the inductor L1 of the filter and rectifier circuit 122; the third end of the first transistor Q1 is also connected to the anode of the first diode D1 and the cathode of the second diode D2, respectively; the cathode of the first diode D1 is connected to the power supply VDD; the anode of the second diode D2 is grounded. The second end of the second transistor Q2 is connected to the power supply and speed control I / O of the software control module 130 via a third resistor R3; the second end of the second transistor Q2 is also grounded via a fourth resistor R4; and the third end of the second transistor Q2 is grounded.

[0086] The other end of the inductor L1 is connected to the hardware control module 110; the other end of the inductor L1 is also connected to the positive electrode of the first capacitor EC1 and one end of the fifth resistor R5 respectively; the negative electrode of the first capacitor EC1 is grounded, and the other end of the fifth resistor R5 is grounded.

[0087] Hardware control module 110 uses a resettable fuse RF1. One end of the resettable fuse RF1 is connected to inductor L1, and the other end is connected to fan 200. It is designed to disconnect when the current of fan 200 exceeds the operating current of hardware control module 110, and to conduct when the current of fan 200 is less than the operating current of hardware control module 110; the operating current is greater than the protection threshold. The specific selection parameters of resettable fuse RF1 require that the operating current I_RF be three times the rated current I_FAN of fan 200, that is, I_RF = 3I_FAN. Furthermore, the rated current of the first transistor Q1 in the circuit is often much greater than I_RF.

[0088] The specific method of implementing hardware overcurrent and short-circuit protection in this circuit is as follows: (1) When the refrigerator turns on the fan 200, the MUC outputs a high level to the power supply and speed control I / O port. At this time, Q2 and tube Q1 are in a saturated working state. The VDD power supply is supplied to the external fan 200 working current after passing through L1, EC1, and R6 in the filter rectifier circuit 122, and then through the self-resettable fuse RF1, and finally returns to the power ground after passing through the second resistor R2. (2) When the fan 200 load is overcurrent, the fan 200 wiring harness is short-circuited, or the fan 200 is stalled, the current Ia flowing through the self-resettable fuse RF1 in the circuit will increase significantly. When Ia>I_RF, it reaches the operating current of RF1, and the self-resettable fuse RF1 is activated, disconnecting the power circuit. At this time, the fan 200 will stop working, and all components in the circuit will also stop working, protecting all components in the circuit from damage. When there is no abnormality in the fan 200 or the connecting harness, Ia<I_RF, the resettable fuse RF1 automatically returns to the conducting state, and the fan 200 circuit returns to the normal working mode.

[0089] In this preferred embodiment, hardware protection and software protection functions are included. The two protection functions work simultaneously. When either function fails, the other protection function still exists, which can protect the circuit, extend the circuit working life, and improve reliability and stability.

[0090] It should be understood that the specific embodiments described herein are only used to explain this application and are not used to limit it. Based on the embodiments provided in this application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0091] Obviously, the accompanying drawings are merely examples or embodiments of the present application. A person skilled in the art can also apply the present application to other similar situations based on these drawings without inventive effort. Furthermore, it is understandable that, although the work involved in this development process may be complex and lengthy, certain design, manufacturing, or production changes based on the technical content disclosed in this application are merely routine technical means for a person skilled in the art and should not be considered to constitute a deficiency in the disclosure of the present application.

[0092] The term "embodiment" as used in this application refers to specific features, structures, or characteristics described in conjunction with the embodiment that can be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily mean that the embodiment is the same, nor does it mean that it is mutually exclusive with other embodiments and is independent or optional. It is understood, either explicitly or implicitly, by those skilled in the art that the embodiments described in this application can be combined with other embodiments when there is no conflict.

[0093] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of patent protection. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present application shall be determined by the appended claims.

Claims

1. A self-protection fan control device, characterized in that: The device is used for a refrigerator, and comprises: a hardware control module, a power module, and a software control module; The software control module is connected to the fan and the power module, and is used to collect the real-time current of the fan and generate a corresponding fan control signal based on the real-time current and a preset protection threshold; The power supply module is also connected to the hardware control module and is used to output a corresponding power drive signal under the action of the fan control signal to control the working state of the fan; The hardware control module is also connected to the fan, and is used to disconnect when the current of the fan is greater than the action current of the hardware control module, and to connect when the current of the fan is less than the action current of the hardware control module; the action current is greater than the protection threshold.

2. The self-protection fan control device according to claim 1, characterized in that: Based on the real-time current and the preset protection threshold, a corresponding wind turbine control signal is generated, including: If the real-time current is greater than a preset first protection threshold and lasts for a preset detection time, a fan shutdown signal is output; If the real-time current is less than the first protection threshold and greater than or equal to a preset second protection threshold, the duty cycle of the fan start signal is reduced until the real-time current is less than the second protection threshold.

3. The self-protection fan control device according to claim 2, characterized in that: The software control module is further configured to perform a restart determination after the hardware control module is triggered, and output a fan start signal if the restart determination meets the requirements and reaches a preset number of consecutive times; The restart determination meeting the requirements includes: after a preset recovery time, the real-time current collected is greater than a preset third protection threshold.

4. The self-protection fan control device according to claim 1, characterized in that: The software control module is further configured to diagnose and predict faults of the fan according to the real-time current, and generate a fan shutdown signal in combination with the diagnosis and prediction results.

5. The self-protection wind turbine control device according to claim 1, characterized in that: The device further comprises a temperature sensor connected to the software control module, the temperature sensor being used to collect the ambient temperature of the self-protection fan control device; The software control module is further configured to increase the set value of the protection threshold according to a decrease in the ambient temperature.

6. The self-protection wind turbine control device according to claim 1, characterized in that: The power supply module includes: a switching circuit and a filtering and rectifying circuit; The switching circuit is connected to the power supply, the filtering and rectifying circuit and the software control module, and is used to output an initial driving signal based on the received fan control signal; The filtering and rectifying circuit is connected to the hardware control module and is used to rectify and filter the initial driving signal to obtain a power driving signal.

7. The self-protection wind turbine control device according to claim 6, characterized in that: The switch circuit includes: a first switch unit and a second switch unit; The first switch unit is connected to the software control module and the second switch unit, and is configured to be turned on or off under the control of the software control module; The second switch unit is further connected to the power supply and the filter rectifier circuit, and is configured to be turned on when the first switch unit is turned on, and turned off when the first switch unit is turned off, so as to generate the corresponding initial drive signal.

8. The self-protection wind turbine control device according to claim 7, characterized in that: The first switch unit includes a first transistor, a first resistor, a second resistor, a first diode and a second diode; the second switch unit includes a second transistor, a third resistor and a fourth resistor; The first end of the first transistor is connected to a power supply; the first end of the first transistor is also connected to the second end of the first transistor via the first resistor; the second end of the first transistor is connected to the first end of the second transistor via the second resistor, and the third end of the first transistor is connected to the filter rectifier circuit; the third end of the first transistor is also connected to the anode of the first diode and the cathode of the second diode respectively; the cathode of the first diode is connected to the power supply; and the anode of the second diode is grounded. The second end of the second transistor is connected to the software control module through the third resistor; the second end of the second transistor is also grounded through the fourth resistor; and the third end of the second transistor is grounded.

9. The self-protection wind turbine control device according to claim 6, characterized in that: The filtering and rectifying circuit comprises: an inductor, a first capacitor and a fifth resistor; One end of the inductor is connected to the switch circuit, and the other end of the inductor is connected to the hardware control module; The other end of the inductor is also connected to the positive electrode of the first capacitor and one end of the fifth resistor respectively; the negative electrode of the first capacitor is grounded, and the other end of the fifth resistor is grounded.

10. A refrigerator, characterized in that: The invention comprises a wind turbine and the self-protection wind turbine control device according to any one of claims 1 to 9.

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