Control method and device of piezoelectric fan, electronic device and storage medium

Abstract

The invention discloses a piezoelectric fan control method, a piezoelectric fan control device, an electronic device and a computer readable storage medium, and relates to the technical field of fan control. The piezoelectric fan is connected with a to-be-cooled device, and the control method comprises the steps that according to the hot spot temperature of a power device of the to-be-cooled device and the temperature of a shell of the to-be-cooled device, operation gears of the piezoelectric fan are determined, and the operation gears comprise the closing gear, the low-power-consumption optimal operation gear and the full-power gear; and under the condition that the operation gear of the piezoelectric fan is the low-power-consumption optimal operation gear, the driving voltage and the working frequency of the piezoelectric fan are adjusted according to a multi-objective function until the parameters of the multi-objective function are reduced to the minimum value, and then the piezoelectric fan is started. The parameters of the multi-objective function comprise fan power consumption and fan noise of the piezoelectric fan. According to the piezoelectric fan, low-power-consumption and low-noise operation can be kept on the premise that safe heat dissipation of the piezoelectric fan is ensured.

Description

Technical Field

[0001] The present application relates to the field of fan control technology, and more specifically, to a control method for a piezoelectric fan, a control device for a piezoelectric fan, an electronic device, and a computer-readable storage medium. Background Art

[0002] As devices like portable energy storage, electric vehicles, and inverters become increasingly miniaturized, the bulky and energy-intensive traditional motor-driven fans struggle to meet the demands of increasingly compact spaces. However, the compact, low-power piezoelectric blower has become an ideal heat dissipation device. The heat dissipation capacity of a piezoelectric blower is affected by parameters such as its vibration amplitude and frequency. Adjusting these parameters to ensure safe heat dissipation while maintaining low power consumption and low noise levels is a pressing issue. Summary of the Invention

[0003] The embodiments of the present application provide a control method for a piezoelectric blower, a control device for a piezoelectric blower, an electronic device, and a computer-readable storage medium, which can ensure that the piezoelectric blower can maintain low power consumption and low noise operation under the premise of safe heat dissipation.

[0004] A control method for a piezoelectric blower in an embodiment of the present application, wherein the piezoelectric blower is connected to a device to be cooled, and the control method comprises: determining an operating gear of the piezoelectric blower according to a hot spot temperature of a power device of the device to be cooled and a shell temperature of the device to be cooled, the operating gear comprising an off gear, a low-power optimal operating gear and a full-power gear; and when the operating gear of the piezoelectric blower is the low-power optimal operating gear, adjusting a driving voltage and an operating frequency of the piezoelectric blower according to a multi-objective function until the parameters of the multi-objective function are reduced to a minimum value, the parameters of the multi-objective function comprising the fan power consumption and fan noise of the piezoelectric blower.

[0005] In some embodiments, determining the operating gear of the piezoelectric blower based on the hot spot temperature of the power device of the device to be dissipated heat and the shell temperature of the device to be dissipated heat includes: when the hot spot temperature of the power device is less than or equal to a first device temperature threshold and the shell temperature is less than or equal to the first shell temperature threshold, determining that the operating gear of the piezoelectric blower is the off gear; when the hot spot temperature of the power device is greater than the first device temperature threshold and the shell temperature is less than the second shell temperature threshold, determining that the operating gear of the piezoelectric blower is the low-power optimal operating gear, and the first shell temperature threshold is less than the second shell temperature threshold; and when the hot spot temperature of the power device is greater than or equal to the second device temperature threshold and the shell temperature is greater than or equal to the second shell temperature threshold, determining that the operating gear of the piezoelectric blower is the full power gear, and the first device temperature threshold is less than the second device temperature threshold.

[0006] In some embodiments, the multi-objective function includes an initial function to be adjusted and an adjusted objective function, and adjusting the driving voltage and operating frequency of the piezoelectric blower according to the multi-objective function until the parameters of the multi-objective function are reduced to a minimum value includes: obtaining the initial function, the initial function including the power consumption weight of the blower power consumption and the noise weight of the blower noise; adjusting the power consumption weight and the noise weight according to the surrounding scene of the piezoelectric blower to obtain the objective function; and adjusting the driving voltage and operating frequency of the piezoelectric blower according to the objective function until the parameters of the objective function are reduced to a minimum value.

[0007] In some embodiments, adjusting the driving voltage and operating frequency of the piezoelectric blower according to the objective function until the parameters of the objective function are reduced to a minimum value includes: obtaining the maximum value of the driving voltage, the lower limit coefficient of the heat dissipation capacity of the piezoelectric blower, and the number of blades of the piezoelectric blower; obtaining the minimum value of the driving voltage according to the lower limit coefficient of the heat dissipation capacity and the number of blades; determining the value range of the driving voltage according to the minimum value of the driving voltage and the maximum value of the driving voltage; obtaining multiple preset initial frequencies, and obtaining multiple preset initial voltages according to the value range of the driving voltage; and calculating the objective function according to the preset initial frequencies and the preset initial voltages, and determining the preset initial frequency and the preset initial voltage corresponding to the minimum value of the objective function as the operating frequency and the driving voltage, respectively.

[0008] In some embodiments, obtaining the lower limit coefficient of the heat dissipation capacity of the piezoelectric blower includes: obtaining the heat generation of the piezoelectric blower based on the power loss ratio and the inverter output power; and determining the lower limit coefficient of the heat dissipation capacity based on the heat generation, the heat exchange surface area of ​​the piezoelectric blower, the hot spot temperature of the power device and the ambient temperature.

[0009] In some embodiments, the obtaining of multiple preset initial frequencies and the obtaining of multiple preset initial voltages based on the value range of the driving voltage include: obtaining multiple preset initial frequencies based on a preset frequency step, and obtaining multiple preset initial voltages based on a preset voltage step and the value range of the driving voltage.

[0010] In some embodiments, the objective function is calculated based on the preset initial frequency and the preset initial voltage, and the preset initial frequency and the preset initial voltage corresponding to the minimum value of the objective function are respectively determined as the operating frequency and the driving voltage, including: obtaining the load equivalent capacitance of the piezoelectric blower, and obtaining the initial power consumption based on the load equivalent capacitance, the preset initial frequency and the preset initial voltage; obtaining the initial noise based on the number of blades, the preset initial frequency and the preset initial voltage; and obtaining the objective function based on the initial power consumption and the initial noise, and determining the preset initial frequency and the preset initial voltage corresponding to the minimum value of the objective function as the operating frequency and the driving voltage, respectively.

[0011] In some embodiments, the control method further includes: when the operating gear of the piezoelectric blower is the off gear, controlling the piezoelectric blower to shut down; and when the operating gear of the piezoelectric blower is the full power gear, controlling the driving voltage and the operating frequency to increase to the maximum value.

[0012] The present application provides a control device for a piezoelectric blower, wherein the piezoelectric blower is connected to a device to be cooled. The control device includes a determination module and an adjustment module. The determination module is used to determine the operating position of the piezoelectric blower based on the hot spot temperature of the power device of the device to be cooled and the housing temperature of the device to be cooled, wherein the operating positions include an off position, a low-power optimal operating position, and a full-power position. The adjustment module is used to adjust the driving voltage and operating frequency of the piezoelectric blower according to a multi-objective function when the operating position of the piezoelectric blower is the low-power optimal operating position until the parameters of the multi-objective function are reduced to a minimum value. The parameters of the multi-objective function include the power consumption and noise of the piezoelectric blower.

[0013] The present application also provides an electronic device, which includes the control device of the piezoelectric blower described in any one of the above embodiments.

[0014] The present application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the control method described in any one of the above embodiments.

[0015] In the control method of the piezoelectric blower, the control device of the piezoelectric blower, the electronic device and the computer-readable storage medium provided in the present application, the piezoelectric blower is connected to the device to be cooled, and when the device to be cooled needs to cool, the piezoelectric blower can cool the device to be cooled. This method determines whether the operating gear of the piezoelectric blower is in the closed gear, the low-power optimal operating gear or the full-power gear through the hot spot temperature of the power device of the device to be cooled and the shell temperature of the device to be cooled, so as to ensure that the temperature of the internal power device and the temperature of the shell of the device to be cooled are not too high. While ensuring that the temperature of the internal power device and the shell temperature of the device to be cooled meet the conditions for normal operation, the driving voltage and operating frequency of the piezoelectric blower are adjusted with the goal of minimizing the two parameters of the piezoelectric blower power consumption and the blower noise in the multi-objective function, so as to ensure that the piezoelectric blower can maintain low power consumption and low noise operation under the premise of safe heat dissipation.

[0016] Additional aspects and advantages of the embodiments of the present application will be given in part in the description below, and in part will become obvious from the description below, or will be learned through practice of the embodiments of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which: Figure 1 is a flow chart of a control method for a piezoelectric blower according to some embodiments of the present application; Figure 2 is a schematic structural diagram of a control device for a piezoelectric blower in some embodiments of the present application; Figure 3 is an example diagram of a piezoelectric blower and a device to be cooled according to some embodiments of the present application; Figure 4 This is a flow chart of determining the operating position of the piezoelectric blower according to the hot spot temperature of the power device of the device to be cooled and the temperature of the housing of the device to be cooled in a control method of the piezoelectric blower in some embodiments of the present application; Figure 5 This is a flow chart of adjusting the driving voltage and operating frequency of a piezoelectric blower according to a multi-objective function until the parameters of the multi-objective function are reduced to a minimum value in a control method of a piezoelectric blower in some embodiments of the present application; Figure 6 This is a flow chart of adjusting the driving voltage and operating frequency of a piezoelectric blower according to an objective function until the parameters of the objective function are reduced to a minimum value in a control method of a piezoelectric blower in some embodiments of the present application; Figure 7 This is a flow chart of obtaining the maximum value of the driving voltage, the lower limit coefficient of the heat dissipation capacity of the piezoelectric blower, and the number of blades of the piezoelectric blower in a control method of a piezoelectric blower in some embodiments of the present application; Figure 8 This is a flow chart of obtaining a plurality of preset initial frequencies and obtaining a plurality of preset initial voltages according to a value range of a driving voltage in a control method for a piezoelectric blower according to some embodiments of the present application; Figure 9 1. A flow chart illustrating a method for controlling a piezoelectric blower according to some embodiments of the present invention, wherein an objective function is calculated based on a preset initial frequency and a preset initial voltage, and the preset initial frequency and the preset initial voltage corresponding to the minimum value of the objective function are determined as the operating frequency and the driving voltage, respectively. Figure 10 is a flow chart of a control method for a piezoelectric blower according to other embodiments of the present application; Figure 11 is a schematic structural diagram of an electronic device according to some embodiments of the present application; Figure 12 This is a schematic diagram of the connection status of a computer-readable storage medium and a processor in certain embodiments of the present application.

[0018] Description of main component symbols: electronic device 100; Control device 10 for piezoelectric blower; Determination module 11; Adjustment module 12; Processor 20; Computer readable storage medium 200; computer program 202; Energy storage inverter 30; Thermally conductive insulating material 40; Power radiator 50; Air duct plate 60; Piezoelectric blower 70. DETAILED DESCRIPTION

[0019] The embodiments of the present application are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the embodiments of the present application, and should not be understood as limiting the embodiments of the present application.

[0020] As electronic devices such as portable energy storage devices, electric vehicle controllers, and high-density inverters continue to evolve toward miniaturization and high integration, the limitations of traditional motor-driven cooling fans are becoming increasingly prominent. The bulk of traditional motor-driven cooling fans, owing to their built-in motor structure and drive mechanism, not only squeezes already extremely tight internal space, but their high rotational energy consumption also conflicts with the current trend of energy conservation and consumption reduction. Therefore, piezoelectric blowers, with their slim and lightweight features, low power consumption, and lack of magnetic interference, have become the preferred cooling solution for these compact power electronic devices. However, the core heat dissipation mechanism of piezoelectric blowers stems from the high-frequency reciprocating oscillation of their metal or ceramic blades under the influence of a driving electric field. This periodic pushing and sucking action of the blades creates an effective fluid layer on their surface, enhancing local heat exchange. The heat dissipation performance of a piezoelectric blower depends on whether the oscillation amplitude can establish a sufficiently wide displacement range at the blade tip and whether it can complete a sufficient number of oscillations per unit time. Therefore, the vibration amplitude and vibration frequency of the piezoelectric blower will affect the heat dissipation effect of the piezoelectric blower. How to adjust these parameters so that the piezoelectric blower can achieve an effective heat dissipation effect while also taking into account low power consumption and low noise is a problem that needs to be solved urgently. To solve this problem, the present application provides a control method for a piezoelectric blower (such as Figure 1 As shown), the control device of the piezoelectric blower (as Figure 2 As shown), electronic devices (such as Figure 11 As shown) and computer readable storage media (such as Figure 12 shown).

[0021] See also Figures 1 to 3 The control method of the piezoelectric blower in the embodiment of the present application is connected to the device to be cooled, and the control method includes: 03: Determine the operating position of the piezoelectric blower according to the hot spot temperature of the power device of the equipment to be cooled and the shell temperature of the equipment to be cooled. The operating positions include the off position, the low power consumption optimal operating position and the full power position; and 05: When the piezoelectric blower is in the low-power optimal operating gear, adjust the driving voltage and operating frequency of the piezoelectric blower according to the multi-objective function until the parameters of the multi-objective function are reduced to the minimum value. The parameters of the multi-objective function include the power consumption and noise of the piezoelectric blower.

[0022] The above-mentioned control method of the piezoelectric blower can be applied to the control device 10 of the piezoelectric blower. The control device 10 of the piezoelectric blower in the embodiment of the present application includes a determination module 11 and an adjustment module 12. The determination module 11 is used to determine the operating gear of the piezoelectric blower according to the hot spot temperature of the power device of the equipment to be cooled and the shell temperature of the equipment to be cooled. The operating gear includes the off gear, the low-power optimal operating gear and the full-power gear. The adjustment module 12 is used to adjust the driving voltage and operating frequency of the piezoelectric blower according to the multi-objective function when the operating gear of the piezoelectric blower is the low-power optimal operating gear, until the parameters of the multi-objective function are reduced to the minimum value. The parameters of the multi-objective function include the fan power consumption and fan noise of the piezoelectric blower.

[0023] Specifically, the piezoelectric blower control device 10 is a core device for controlling the piezoelectric blower to achieve the heat dissipation function. The piezoelectric blower control device 10 is a physical device that integrates hardware and software logic. The piezoelectric blower control device 10 can be set on the internal control module, control device or controller of the piezoelectric blower, or it can be set on other devices for remotely controlling the operation of the piezoelectric blower. The piezoelectric blower control device 10 achieves the heat dissipation effect of the piezoelectric blower in the heat dissipation scenario through temperature perception, gear decision-making and operation parameter optimization, while also ensuring the low power consumption and low noise operation of the piezoelectric blower. The specific functions of the piezoelectric blower control device 10 include temperature monitoring, gear switching, drive parameter adjustment and multi-objective optimization algorithm, etc., which will be explained in detail below.

[0024] More specifically, the piezoelectric blower control device 10 includes a determination module 11 and an adjustment module 12. The determination module 11 is one of the core functional units of the piezoelectric blower control device 10. It is a logic module that determines the operating status of the piezoelectric blower based on data obtained from real-time monitoring of the hotspot temperature of the power device and the temperature of the device casing. The adjustment module 12 is also one of the core functional units of the piezoelectric blower control device 10. It is an execution module that optimizes various operating parameters of the piezoelectric blower (such as drive voltage and operating frequency) at the optimal low-power operating position.

[0025] Furthermore, the piezoelectric blower is connected to a device to be cooled. There is no special requirement for the type of device to be cooled. Any device that generates heat during operation can be a device to be cooled. Figure 3 ,exist Figure 3In the example, the device to be dissipated heat is the energy storage inverter 30. Energy storage inverter 30 is the source of heat and the object to be cooled. Thermally conductive insulating material 40 is provided on at least one side of the energy storage inverter 30. This material fills the tiny gap between the power device (e.g., energy storage inverter 30) and the power heat sink 50, reducing contact thermal resistance and efficiently transferring heat from the power device (e.g., energy storage inverter 30) to the power heat sink 50. The thermally conductive insulating material 40 can be any thin, flexible thermally conductive sheet, or silicone grease or phase change material applied to the power device (e.g., energy storage inverter 30). The power heat sink 50 receives heat transferred from the thermally conductive insulating material 40 and dissipates the heat to the surrounding air through conduction and convection, utilizing the large surface area provided by its numerous fins. The duct plate 60 forms a channel (air duct) around the fin area of ​​the power heat sink 50. This forces the airflow (driven by the piezoelectric blower 70) to flow through the narrow gaps between the fins of the power heat sink 50, maximizing the contact area between the airflow and the heat sink fins and improving heat exchange efficiency. The piezoelectric blower 70 is used to generate a directional airflow (usually along the direction of the duct), forcing air to flow through the fins of the power heat sink 50 within the duct at a specific speed and flow rate.

[0026] Furthermore, the core component of a piezoelectric blower is a piezoelectric element (such as a piezoelectric ceramic). When an alternating voltage is applied to the piezoelectric blower, the piezoelectric element deforms (bends upward or downward) due to the inverse piezoelectric effect. This deformation causes the attached metal or plastic blades to vibrate, which in turn promotes the flow of surrounding air, removing heat and achieving heat dissipation.

[0027] Furthermore, in step 03, the hotspot temperature of the power device within the heat dissipation device refers to the highest operating temperature of the power conversion elements (such as MOS tubes and insulated gate bipolar transistors) within the heat dissipation device. Therefore, the hotspot temperature of the power device directly reflects the thermal load status of the core heat-generating components of the heat dissipation device and is a key indicator for triggering the start, stop, and gear switching of the piezoelectric blower. The housing temperature of the heat dissipation device refers to the temperature of the outer surface of the heat dissipation device. This temperature reflects the overall heat dissipation status of the device. Together with the hotspot temperature of the power devices within the heat dissipation device, the housing temperature of the heat dissipation device forms the temperature criterion for fan gear switching, preventing misadjustment due to local temperature measurement errors. The operating gears of the piezoelectric blower include the off gear, the low-power optimal operating gear, and the full-power gear. Information about these gears is further explained below.

[0028] Furthermore, in step 05, the multi-objective function can be a mathematical model containing parameters and each parameter has a weight coefficient corresponding to itself. In the present application, the parameters of the multi-objective function include the fan power consumption and fan noise of the piezoelectric fan, and the fan power consumption and fan noise are related to the driving voltage and operating frequency of the piezoelectric fan. Relevant personnel can meet the requirements of different scenarios by adjusting the weight coefficient corresponding to the fan power consumption and the weight coefficient corresponding to the fan noise.

[0029] Furthermore, the driving voltage is the voltage applied to the piezoelectric element (such as a piezoelectric ceramic) of a piezoelectric blower. The higher the driving voltage, the greater the deformation of the piezoelectric element, the larger the amplitude, and the greater the air volume. The operating frequency refers to the frequency of the driving voltage and is proportional to the deformation frequency of the piezoelectric element.

[0030] It can be understood that the present application provides a control method for a piezoelectric blower, in which the piezoelectric blower is connected to a device to be cooled, and when the device to be cooled needs to dissipate heat, the piezoelectric blower can dissipate heat for the device to be cooled. This method determines whether the operating gear of the piezoelectric blower is in the closed gear, the low-power optimal operating gear, or the full-power gear through the hot spot temperature of the power device of the device to be cooled and the shell temperature of the device to be cooled, so as to ensure that the temperature of the internal power device and the shell temperature of the device to be cooled are not too high. While ensuring that the temperature of the internal power device and the shell temperature of the device to be cooled meet the conditions for normal operation, the driving voltage and operating frequency of the piezoelectric blower are adjusted with the goal of minimizing the two parameters of the piezoelectric blower power consumption and the blower noise in the multi-objective function, so as to ensure that the piezoelectric blower can maintain low power consumption and low noise operation under the premise of safe heat dissipation.

[0031] In certain embodiments, see Figure 4 ,03: According to the hot spot temperature of the power device of the equipment to be cooled and the shell temperature of the equipment to be cooled, determine the operating position of the piezoelectric blower, including: 031: when the hot spot temperature of the power device is less than or equal to the first device temperature threshold and the housing temperature is less than or equal to the first housing temperature threshold, determining that the operating gear of the piezoelectric blower is the off gear; 032: When the hot spot temperature of the power device is greater than a first device temperature threshold and the housing temperature is less than a second housing temperature threshold, determining that the operating gear of the piezoelectric blower is a low-power optimal operating gear, and the first housing temperature threshold is less than the second housing temperature threshold; and 033: When the hot spot temperature of the power device is greater than or equal to the second device temperature threshold and the housing temperature is greater than or equal to the second housing temperature threshold, it is determined that the operating gear of the piezoelectric blower is the full power gear and the first device temperature threshold is less than the second device temperature threshold.

[0032] The above-mentioned control method of the piezoelectric blower can be applied to the control device 10 of the piezoelectric blower. The determination module 11 of the embodiment of the present application is also used to determine that the operating gear of the piezoelectric blower is the closed gear when the hot spot temperature of the power device is less than or equal to the first device temperature threshold and the shell temperature is less than or equal to the first shell temperature threshold; when the hot spot temperature of the power device is greater than the first device temperature threshold and the shell temperature is less than the second shell temperature threshold, the operating gear of the piezoelectric blower is determined to be the low-power optimal operating gear, and the first shell temperature threshold is less than the second shell temperature threshold; when the hot spot temperature of the power device is greater than or equal to the second device temperature threshold and the shell temperature is greater than or equal to the second shell temperature threshold, the operating gear of the piezoelectric blower is determined to be the full power gear, and the first device temperature threshold is less than the second device temperature threshold.

[0033] Specifically, if the hot spot temperature of the power device is less than or equal to the first device temperature threshold (which can be set by relevant personnel according to actual conditions) and the casing temperature is less than or equal to the first casing temperature threshold (which can be set by relevant personnel according to actual conditions), it indicates that the temperature of the device to be cooled has not risen to the level that requires the piezoelectric blower to dissipate heat. At this time, the device to be cooled may have just been started or has not yet been started. Therefore, the piezoelectric blower is determined to be in the off position.

[0034] Specifically, if the hot spot temperature of the power device is greater than the first device temperature threshold (which can be set by relevant personnel according to actual conditions) and the casing temperature is less than the second casing temperature threshold (which can be set by relevant personnel according to actual conditions, and the first casing temperature threshold is less than the second casing temperature threshold), it indicates that the temperature of the device to be cooled has risen to a level that requires a piezoelectric blower to dissipate heat. At this time, the device to be cooled may have been running for a period of time. Therefore, the piezoelectric blower is determined to be in the low-power optimal operating position.

[0035] Specifically, if the hot spot temperature of the power device is greater than or equal to the second device temperature threshold (which can be set by relevant personnel according to actual conditions, and the first device temperature threshold is less than the second device temperature threshold) and the casing temperature is greater than or equal to the second casing temperature threshold (which can be set by relevant personnel according to actual conditions, and the first casing temperature threshold is less than the second casing temperature threshold), it indicates that the temperature of the device to be cooled has risen to a high level and needs to be lowered as soon as possible. At this time, the device to be cooled may have been running for a long time. Therefore, the piezoelectric blower is determined to be at full power gear at this time to lower the temperature of the device to be cooled as soon as possible.

[0036] Please combine Figure 5 In some embodiments, the multi-objective function includes an initial function to be adjusted and an adjusted objective function. 05: According to the multi-objective function, adjusting the driving voltage and operating frequency of the piezoelectric blower until the parameters of the multi-objective function are reduced to a minimum value includes: 051: Obtain an initial function, which includes a power consumption weight of the fan power consumption and a noise weight of the fan noise; 053: According to the surrounding scene of the piezoelectric blower, adjust the power consumption weight and noise weight to obtain the objective function; and 055: According to the objective function, adjust the driving voltage and operating frequency of the piezoelectric blower until the parameters of the objective function are reduced to the minimum value.

[0037] The above-mentioned control method of the piezoelectric blower can be applied to the control device 10 of the piezoelectric blower. The adjustment module 12 of the embodiment of the present application is also used to: obtain an initial function, the initial function includes the power consumption weight of the blower power consumption and the noise weight of the blower noise; adjust the power consumption weight and noise weight according to the surrounding scene of the piezoelectric blower to obtain the target function; according to the target function, adjust the driving voltage and operating frequency of the piezoelectric blower until the parameters of the target function are reduced to the minimum value.

[0038] Specifically, the initial function includes the power consumption weight of the fan power consumption and the noise weight of the fan noise. The initial function can be a weighted and multi-objective optimization model: J = w1 • P fan (fan power consumption) + w2•L noise (fan noise), where w1 is the weight coefficient corresponding to fan power consumption, and w2 is the weight coefficient corresponding to fan noise.

[0039] Furthermore, relevant personnel can adjust the power consumption weight and noise weight according to the surrounding scene of the piezoelectric fan to obtain the objective function. For example, if the current scene is nighttime, the priority can be to reduce noise and increase the weight coefficient corresponding to fan noise, that is, increase w2 and reduce w1. If the current scene is nighttime, the priority can be to reduce fan power consumption and increase the weight coefficient corresponding to fan power consumption, that is, increase w1 and reduce w2.

[0040] Furthermore, after adjusting the power consumption and noise weights based on the surrounding scene to obtain the objective function, the piezoelectric blower's drive voltage and operating frequency can be adjusted according to the objective function until the parameters of the objective function are reduced to the minimum value. This process is explained in detail below.

[0041] See also Figure 6 In some embodiments, 055: adjusting the driving voltage and operating frequency of the piezoelectric blower according to the objective function until the parameters of the objective function are reduced to a minimum value, including: 0551: Get the maximum value of the driving voltage, the lower limit coefficient of the heat dissipation capacity of the piezoelectric fan, and the number of blades of the piezoelectric fan; 0552: According to the lower limit coefficient of heat dissipation capacity and the number of blades, the minimum value of the driving voltage is obtained; 0553: Determine the value range of the driving voltage according to the minimum value and the maximum value of the driving voltage; 0554: Obtain multiple preset initial frequencies, and obtain multiple preset initial voltages according to the value range of the driving voltage; and 0555: Calculate the objective function according to the preset initial frequency and the preset initial voltage, and determine the preset initial frequency and the preset initial voltage corresponding to the minimum value of the objective function as the operating frequency and the driving voltage, respectively.

[0042] The above-mentioned control method of the piezoelectric blower can be applied to the control device 10 of the piezoelectric blower. The adjustment module 12 of the embodiment of the present application is also used to: obtain the maximum value of the driving voltage, the lower limit coefficient of the heat dissipation capacity of the piezoelectric blower and the number of blades of the piezoelectric blower; obtain the minimum value of the driving voltage according to the lower limit coefficient of the heat dissipation capacity and the number of blades; determine the value range of the driving voltage according to the minimum value of the driving voltage and the maximum value of the driving voltage; obtain multiple preset initial frequencies, and obtain multiple preset initial voltages according to the value range of the driving voltage; calculate the objective function according to the preset initial frequencies and the preset initial voltages, and determine the preset initial frequency and the preset initial voltage corresponding to the minimum value of the objective function as the operating frequency and the driving voltage, respectively.

[0043] Specifically, based on the lower limit coefficient of the heat dissipation capacity and the number of blades, the minimum value of the driving voltage can be obtained, and the maximum value of the driving voltage is the calibration parameter of the piezoelectric blower itself. Therefore, after obtaining the minimum value and the maximum value of the driving voltage, the value range of the driving voltage can be obtained. The operating frequency also has an upper limit (which is also a calibration parameter of the piezoelectric blower). The adjustment module 12 takes multiple initial frequencies and multiple initial voltages according to a certain rule within the interval and substitutes them into the objective function for calculation. Afterwards, the adjustment module 12 determines the initial frequency and initial voltage corresponding to the minimum value of the objective function as the operating frequency and driving voltage of the piezoelectric blower.

[0044] Furthermore, since the objective function is J=w1•P fan (fan power consumption) + w2•L noise (fan noise), therefore, by substituting multiple initial frequencies and multiple initial voltage groups into the objective function, different objective function values ​​can be obtained. Among them, the formula for fan power consumption is as follows: ; Among them, P fan Refers to the fan power consumption, C load Refers to the equivalent capacitance of the piezoelectric blower, V drv= is the driving voltage, and f is the operating frequency. This formula essentially comes from the calculation of AC power consumption for capacitive loads. The driving voltage provided to the piezoelectric blower is a high-frequency AC voltage applied to the piezoelectric ceramic, so the piezoelectric blower is essentially a pure capacitive load. In a pure capacitive load, there is no resistance dissipation, and energy is entirely determined by the establishment and release of the electric field. Each cycle is charged and discharged once, and the energy consumed is 1 / 2*C (capacitance)*V. 2 (the square of the driving voltage), which occurs f (the operating frequency) times per second, so the power consumption is the above energy multiplied by the operating frequency.

[0045] Furthermore, the fan noise is publicized as follows: ; Among them, L noise is the fan noise, α and β are fitting coefficients, which can be determined through prototype testing or based on the experience of relevant personnel. blades is the number of blades of the piezoelectric blower. N blades •V drv • f represents the intensity factor of the noise source (e.g., the product of velocity, air volume, and power). The product of these three parameters represents the equivalent vibration intensity factor of the fan (the higher the air volume, the greater the noise). The logarithmic function reflects the human ear's perception of noise (which is logarithmic). α determines the sensitivity to noise increase (for example, when α = 20, a 10-fold change in sound pressure equates to a 20dB increase in noise). β determines the minimum noise baseline (the background noise) when there is no air flow.

[0046] Furthermore, for example, assuming that the power consumption weight and noise weight are determined to be 0.7 and 0.3 respectively based on the surrounding scene, the following table can be obtained based on the calibration parameters of the piezoelectric blower (such as the maximum drive voltage, the number of blades, the maximum operating frequency, etc.): Table 1 Parameter example table

[0047] From Table 1 above, we can assume that the operating frequency f=100 Hz and calculate the corresponding lower limit of the driving voltage as V drv,min =K / N blades •f=200 / (5×100)=200 / 500=0.4 V, voltage upper limit V drv,max =12 V, so the driving voltage range is V drv ∈[0.4 V, 12 V]. Take an example voltage V in the driving voltage range drv =6 V Fan power consumption: P fan =1 / 2•0.01•(6) 2• 100 = 18, fan noise: L noise =10•log(5•6•100)+30=110.06. At this time, the objective function J=0.7•18+0.3•110.06=45.618.

[0048] Further, change V drv and f, repeatedly repeat the above steps, and finally find the minimum value of the objective function. For example, take: V drv =8 V, f=120 Hz Similarly, calculate: V drv,min =200 / 5•120≈0.33 V, the value range of the driving voltage is 0.33V~12V. At this time, the fan power consumption is 38.4. The fan noise is 114.7. The objective function: J=0.7•38.4+0.3•114.7=61.2. Comparing the two sets of results can see that the value of the objective function of the second group is higher, indicating that the compromise of energy efficiency and noise under the first group of parameters is better. The numerical value of the objective function represents the comprehensive cost when the fan is running. The smaller the numerical value of the objective function, the better the comprehensive score (taking into account low energy consumption and low noise).

[0049] Please refer to Figure 7 In some embodiments, 0551: obtaining the heat dissipation capacity lower limit coefficient of the piezoelectric fan, comprising: 05511: obtaining the heat generation of the piezoelectric fan according to the power loss ratio and the inverter output power; and 05513: determining the heat dissipation capacity lower limit coefficient according to the heat generation, the heat exchange surface area of the piezoelectric fan, the power device hotspot temperature, and the environment temperature.

[0050] The control method of the piezoelectric fan described above can be applied to the control device 10 of the piezoelectric fan. The adjustment module 12 of the embodiment of the application is further used for: obtaining the heat generation of the piezoelectric fan according to the power loss ratio and the inverter output power; and determining the heat dissipation capacity lower limit coefficient according to the heat generation, the heat exchange surface area of the piezoelectric fan, the power device hotspot temperature, and the environment temperature.

[0051] Specifically, the calculation formula of the fan heat generation is as follows: Q gen =η loss •P out , wherein η loss ∈[0.03, 0.1] is used to reflect the device loss ratio. Qgen is the heat generation, and Pout is the output power of the inverter. Then, the heat dissipation capacity lower limit coefficient can be calculated according to the following formula: ; wherein K is the heat dissipation capacity lower limit coefficient, A surf is the heat exchange surface area of the piezoelectric fan, T coreis the hot spot temperature of the power device, T amb is the ambient temperature, and C is the specific heat capacity of the surrounding air. A higher C indicates better heat dissipation. The exponent 1 / n is added because air volume and heat transfer capacity are often not completely linearly related. As air volume increases, the cooling capacity per unit volume gradually decreases. Therefore, a nonlinear factor is introduced to correct the formula.

[0052] See also Figure 8 In some embodiments, 0554: obtaining a plurality of preset initial frequencies, and obtaining a plurality of preset initial voltages according to a value range of the driving voltage, includes: 05541: According to a preset frequency step, a plurality of preset initial frequencies are obtained, and according to a preset voltage step and a value range of a driving voltage, a plurality of preset initial voltages are obtained.

[0053] The above-mentioned control method of the piezoelectric blower can be applied to the control device 10 of the piezoelectric blower. The adjustment module 12 of the embodiment of the present application is also used to obtain multiple preset initial frequencies according to the preset frequency step, and to obtain multiple preset initial voltages according to the preset voltage step and the value range of the driving voltage.

[0054] Specifically, the preset frequency step size and the preset voltage step size can be set by the relevant personnel. For example, assuming the preset frequency step size is set to 10Hz and the preset voltage step size is set to 0.1V, then the initial frequency value is taken from 0 to the maximum operating frequency, taking a value every 10Hz. The initial voltage value is taken from the minimum value of the driving voltage, taking a value every 0.1V until the maximum driving voltage. Then, all combinations of initial frequencies and initial voltages are exhausted to calculate the value of the objective function.

[0055] See also Figure 9 In some embodiments, 0555: calculating an objective function based on a preset initial frequency and a preset initial voltage, and determining the preset initial frequency and the preset initial voltage corresponding to the minimum value of the objective function as the operating frequency and the driving voltage, respectively, includes: 05551: Obtain the load equivalent capacitance of the piezoelectric blower, and obtain the initial power consumption based on the load equivalent capacitance, the preset initial frequency, and the preset initial voltage; 05553: Obtaining initial noise according to the number of blades, the preset initial frequency, and the preset initial voltage; and 05555: According to the initial power consumption and the initial noise, an objective function is obtained, and a preset initial frequency and a preset initial voltage corresponding to the minimum value of the objective function are respectively determined as the operating frequency and the driving voltage.

[0056] The above-mentioned control method of the piezoelectric blower can be applied to the control device 10 of the piezoelectric blower. The adjustment module 12 of the embodiment of the present application is also used to: obtain the load equivalent capacitance of the piezoelectric blower, and obtain the initial power consumption based on the load equivalent capacitance, the preset initial frequency and the preset initial voltage; obtain the initial noise based on the number of blades, the preset initial frequency and the preset initial voltage; and obtain the objective function based on the initial power consumption and the initial noise, and determine the preset initial frequency and the preset initial voltage corresponding to the minimum value of the objective function as the operating frequency and the driving voltage, respectively.

[0057] Specifically, the calculation process of the initial power consumption and the initial noise has been explained above and will not be repeated here.

[0058] See also Figure 10 In some embodiments, the control method further comprises: 04: When the operating gear of the piezoelectric blower is the off gear, control the piezoelectric blower to be off; and 06: When the piezoelectric blower is operating at full power, the control drive voltage and operating frequency are both increased to the maximum value.

[0059] The above-described piezoelectric blower control method can be applied to a piezoelectric blower control device 10, which further includes a first control module and a second control module. The first control module is configured to control the piezoelectric blower to shut down when the piezoelectric blower is in the off position. The second control module is configured to control the drive voltage and operating frequency to their maximum values ​​when the piezoelectric blower is in the full power position.

[0060] It can be understood that when the operating gear of the piezoelectric blower is the off gear, the piezoelectric blower no longer needs to run, and the first control module controls the piezoelectric blower to shut down. When the operating gear of the piezoelectric blower is the full power gear, the piezoelectric blower needs to run at the maximum amplitude and maximum operating frequency, and the second control module controls the driving voltage and operating frequency to increase to the maximum value.

[0061] In summary, in the control method of the piezoelectric blower provided in the present application, the piezoelectric blower is connected to the device to be cooled, and when the device to be cooled needs to dissipate heat, the piezoelectric blower can dissipate heat for the device to be cooled. This method determines whether the operating gear of the piezoelectric blower is in the closed gear, the low-power optimal operating gear, or the full-power gear through the hot spot temperature of the power device of the device to be cooled and the shell temperature of the device to be cooled, so as to ensure that the temperature of the internal power device and the temperature of the shell of the device to be cooled are not too high. While ensuring that the temperature of the internal power device and the shell temperature of the device to be cooled meet the conditions for normal operation, the driving voltage and operating frequency of the piezoelectric blower are adjusted with the goal of minimizing the two parameters of the piezoelectric blower power consumption and the blower noise in the multi-objective function, so as to ensure that the piezoelectric blower can maintain low power consumption and low noise operation under the premise of safe heat dissipation.

[0062] See also Figure 11 In certain embodiments, the present application further provides an electronic device 100, comprising the piezoelectric blower control device 10 in any of the above embodiments. See also Figure 12 In some embodiments, the present application further provides a computer-readable storage medium 200 on which a computer program 202 is stored. When the program is executed by a processor, the method in any of the above embodiments is implemented.

[0063] For example, when the computer program 202 is executed by the processor 20, the following method is implemented: 03: Determine the operating position of the piezoelectric blower according to the hot spot temperature of the power device of the equipment to be cooled and the shell temperature of the equipment to be cooled. The operating positions include the off position, the low power consumption optimal operating position and the full power position; and 05: When the piezoelectric blower is in the low-power optimal operating gear, adjust the driving voltage and operating frequency of the piezoelectric blower according to the multi-objective function until the parameters of the multi-objective function are reduced to the minimum value. The parameters of the multi-objective function include the power consumption and noise of the piezoelectric blower.

[0064] For another example, when the computer program 202 is executed by the processor 20, the following method is implemented: 031: when the hot spot temperature of the power device is less than or equal to the first device temperature threshold and the housing temperature is less than or equal to the first housing temperature threshold, determining that the operating gear of the piezoelectric blower is the off gear; 032: When the hot spot temperature of the power device is greater than a first device temperature threshold and the housing temperature is less than a second housing temperature threshold, determining that the operating gear of the piezoelectric blower is a low-power optimal operating gear, and the first housing temperature threshold is less than the second housing temperature threshold; and 033: When the hot spot temperature of the power device is greater than or equal to the second device temperature threshold and the housing temperature is greater than or equal to the second housing temperature threshold, it is determined that the operating gear of the piezoelectric blower is the full power gear and the first device temperature threshold is less than the second device temperature threshold.

[0065] For another example, when the computer program 202 is executed by the processor 20, the methods in 04, 051, 053, 055, 0551, 05511, 05513, 0552, 0553, 0554, 05541, 0555, 05551, 05553, 05555 and 06 can also be implemented.

[0066] In the computer-readable storage medium 200 in the present application, the piezoelectric blower is connected to the device to be cooled, and when the device to be cooled needs to dissipate heat, the piezoelectric blower can dissipate heat for the device to be cooled. This method determines whether the operating gear of the piezoelectric blower is in the closed gear, the low-power optimal operating gear, or the full-power gear through the hot spot temperature of the power device of the device to be cooled and the shell temperature of the device to be cooled, so as to ensure that the temperature of the internal power device of the device to be cooled and the temperature of the shell are not too high. While ensuring that the temperature of the internal power device and the shell temperature of the device to be cooled meet the conditions for normal operation, the driving voltage and operating frequency of the piezoelectric blower are adjusted with the goal of minimizing the two parameters of the piezoelectric blower power consumption and the blower noise in the multi-objective function, so as to ensure that the piezoelectric blower can maintain low power consumption and low noise operation under the premise of safe heat dissipation.

[0067] In the description of this specification, the reference terms "certain embodiments", "in an example", "exemplarily", etc. mean that the specific features, structures, materials or characteristics described in conjunction with the embodiments or examples are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are mutually inconsistent.

[0068] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, segment or portion of code comprising one or more executable instructions for implementing the steps of a specific logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may be performed out of the order shown or discussed, including performing functions in a substantially simultaneous manner or in the reverse order depending on the functions involved, which should be understood by those skilled in the art to which the embodiments of the present application belong.

[0069] Although the embodiments of the present application have been shown and described above, it is understood that the above-described embodiments are exemplary and are not to be construed as limiting the present application, and that changes, modifications, substitutions and variations can be made by those skilled in the art without departing from the scope of the present application.

Claims

1. A method for controlling a piezoelectric blower, characterized in that: The piezoelectric blower is connected to the device to be cooled, and the control method includes: Determining an operating position of the piezoelectric blower according to a hot spot temperature of a power device of the device to be cooled and a shell temperature of the device to be cooled, wherein the operating position includes an off position, a low power consumption optimal operating position, and a full power position; and When the operating gear of the piezoelectric blower is the low-power optimal operating gear, the driving voltage and operating frequency of the piezoelectric blower are adjusted according to the multi-objective function until the parameters of the multi-objective function are reduced to the minimum value. The parameters of the multi-objective function include the blower power consumption and blower noise of the piezoelectric blower.

2. The control method according to claim 1, characterized in that: The step of determining the operating position of the piezoelectric blower according to the hot spot temperature of the power device of the device to be cooled and the shell temperature of the device to be cooled comprises: When the hot spot temperature of the power device is less than or equal to a first device temperature threshold and the housing temperature is less than or equal to a first housing temperature threshold, determining that the operating gear of the piezoelectric blower is the closed gear; When the hot spot temperature of the power device is greater than a first device temperature threshold and the housing temperature is less than a second housing temperature threshold, determining that the operating gear of the piezoelectric blower is the low-power optimal operating gear, and the first housing temperature threshold is less than the second housing temperature threshold; and When the hot spot temperature of the power device is greater than or equal to the second device temperature threshold and the casing temperature is greater than or equal to the second casing temperature threshold, the operating gear of the piezoelectric blower is determined to be the full power gear, and the first device temperature threshold is less than the second device temperature threshold.

3. The control method according to claim 1, wherein: The multi-objective function includes an initial function to be adjusted and an adjusted objective function, and adjusting the driving voltage and operating frequency of the piezoelectric blower according to the multi-objective function until the parameters of the multi-objective function are reduced to a minimum value includes: Obtaining the initial function, where the initial function includes a power consumption weight of the fan power consumption and a noise weight of the fan noise; Adjusting the power consumption weight and the noise weight according to the surrounding scene of the piezoelectric blower to obtain the objective function; and According to the objective function, the driving voltage and the operating frequency of the piezoelectric blower are adjusted until the parameters of the objective function are reduced to a minimum value.

4. The control method according to claim 3, characterized in that: The step of adjusting the driving voltage and operating frequency of the piezoelectric blower according to the objective function until the parameters of the objective function are reduced to a minimum value includes: Obtaining the maximum value of the driving voltage, the lower limit coefficient of the heat dissipation capacity of the piezoelectric blower, and the number of blades of the piezoelectric blower; Obtaining a minimum value of the driving voltage according to the heat dissipation capacity lower limit coefficient and the number of blades; determining a value range of the driving voltage according to the minimum value of the driving voltage and the maximum value of the driving voltage; Acquire a plurality of preset initial frequencies, and acquire a plurality of preset initial voltages according to the value range of the driving voltage; and The objective function is calculated according to the preset initial frequency and the preset initial voltage, and the preset initial frequency and the preset initial voltage corresponding to the minimum value of the objective function are respectively determined as the operating frequency and the driving voltage.

5. The control method according to claim 4, wherein: The obtaining of the lower limit coefficient of the heat dissipation capacity of the piezoelectric blower includes: Obtaining the heat generated by the piezoelectric blower according to the power loss ratio and the inverter output power; and The heat dissipation capacity lower limit coefficient is determined according to the heat generation, the heat exchange surface area of ​​the piezoelectric blower, the hot spot temperature of the power device and the ambient temperature.

6. The control method according to claim 4, characterized in that: The step of obtaining a plurality of preset initial frequencies and obtaining a plurality of preset initial voltages according to the value range of the driving voltage includes: According to the preset frequency step, a plurality of the preset initial frequencies are obtained, and according to the preset voltage step and the value range of the driving voltage, a plurality of preset initial voltages are obtained.

7. The control method according to claim 4, characterized in that: The step of calculating the objective function according to the preset initial frequency and the preset initial voltage, and determining the preset initial frequency and the preset initial voltage corresponding to the minimum value of the objective function as the operating frequency and the driving voltage, respectively, includes: Obtaining a load equivalent capacitance of the piezoelectric blower, and obtaining an initial power consumption according to the load equivalent capacitance, the preset initial frequency, and the preset initial voltage; Obtaining initial noise according to the number of blades, the preset initial frequency, and the preset initial voltage; and The objective function is obtained according to the initial power consumption and the initial noise, and the preset initial frequency and the preset initial voltage corresponding to the minimum value of the objective function are respectively determined as the operating frequency and the driving voltage.

8. The control method according to claim 1, wherein: The control method further includes: When the operating gear of the piezoelectric blower is the closing gear, controlling the piezoelectric blower to close; and When the operating gear of the piezoelectric blower is the full-power gear, the driving voltage and the operating frequency are controlled to be increased to maximum values.

9. A control device for a piezoelectric blower, characterized in that: The piezoelectric blower is connected to the device to be cooled, and the control device includes: a determination module, configured to determine an operating position of the piezoelectric blower according to a hot spot temperature of a power device of the device to be cooled and a temperature of a housing of the device to be cooled, wherein the operating position includes an off position, a low power consumption optimal operating position, and a full power position; and An adjustment module is used to adjust the driving voltage and operating frequency of the piezoelectric blower according to a multi-objective function when the operating gear of the piezoelectric blower is the low-power optimal operating gear, until the parameters of the multi-objective function are reduced to a minimum value. The parameters of the multi-objective function include the blower power consumption and blower noise of the piezoelectric blower.

10. An electronic device, characterized in that: The electronic device includes the control device of the piezoelectric blower according to claim 9.

11. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the control method according to any one of claims 1 to 8 is implemented.

Images