Direct current fan motor control method, circuit, device, and storage medium

Abstract

The present application relates to the technical field of motor control, and particularly relates to a DC fan motor control method, circuit, device and storage medium, a DC fan motor control circuit comprises a control unit, a power supply unit, a signal detection unit and a driving unit, one end of the power supply unit and one end of the signal detection unit are connected with a speed regulator respectively, the other end of the power supply unit and the other end of the signal detection unit are connected with the control unit respectively, the control unit is connected with the driving unit, the driving unit is connected with the DC fan motor, the method comprises the following steps: after the power supply unit converts the AC voltage of the speed regulator into a stable voltage, the signal detection unit collects the voltage signal of the speed regulator multiple times within a preset time, the physical gear of the speed regulator is judged based on the obtained voltage signal set, the PWM control signal corresponding to the physical gear is confirmed, the execution instruction is generated based on the PWM control signal, the driving unit drives the DC fan motor based on the execution instruction, and the problem that the DC fan controller is incompatible with the traditional speed regulator is solved.

Description

Technical Field

[0001] This invention relates to the field of motor control technology, and in particular to a DC fan motor control method, circuit, device, and storage medium. Background Technology

[0002] Traditional AC fans generally use capacitor-type speed controllers, which use mechanical switches to switch capacitors of different capacities connected in series in the AC circuit, thereby changing the voltage and phase applied to the single-phase AC motor and achieving stepped speed regulation at high, medium, and low speeds. These speed controllers have a large market presence due to their simple structure, low cost, durability, and reliability, and have cultivated stable user habits, leading to their widespread application in various scenarios.

[0003] With the increasing demand for energy conservation and intelligent technology, fans using brushless DC motors are gradually replacing traditional AC fans and becoming the mainstream in the market due to their significant advantages such as high efficiency, low noise, and stepless speed regulation. However, existing DC fan controllers typically require dedicated electronic speed controllers and are incompatible with existing capacitor-type AC speed controllers, resulting in serious compatibility issues that hinder the market penetration and replacement of traditional AC fans by DC fans. If users directly connect a DC fan to an existing capacitor-type AC speed controller, the DC controller cannot correctly identify the speed signal, often resulting in the motor not turning, running at full speed, or malfunctioning, failing to achieve normal speed regulation. To enjoy the advantages of DC fans, users must replace the pre-installed speed control switch and related wiring in the wall, which not only involves a complex installation process but also incurs high upgrade costs, further restricting the market replacement speed of traditional AC fans by DC fans. Summary of the Invention

[0004] In order to overcome the shortcomings of the prior art, the present invention aims to provide a DC fan motor control method, circuit, device and storage medium, which aims to accurately detect and analyze the AC voltage waveform signal from the conventional capacitor AC speed controller, and map the different speed signals to the target speed of the DC motor.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A method for controlling a DC fan motor includes a DC fan motor control circuit comprising a control unit, a power supply unit, a signal detection unit, and a drive unit. One end of the power supply unit and one end of the signal detection unit are respectively connected to a speed controller, and the other ends of the power supply unit and the signal detection unit are respectively connected to the control unit. The control unit is connected to the drive unit, and the drive unit is connected to the DC fan motor. The method includes: controlling the power supply unit to convert the AC voltage of the speed controller into a stable voltage; controlling the signal detection unit to repeatedly collect the voltage signal of the speed controller within a preset time period to obtain a voltage signal set; determining the physical gear of the speed controller based on the voltage signal set; confirming the PWM control signal corresponding to the physical gear and generating an execution command based on the PWM control signal; and controlling the drive unit to drive the DC fan motor based on the execution command.

[0006] In the aforementioned DC fan motor control method, the power supply unit includes an AC / DC conversion group and a voltage regulator group, which are connected to each other. Controlling the power supply unit to convert the AC voltage of the speed controller into a stable voltage includes: controlling the AC / DC conversion group to acquire the AC voltage of the speed controller and performing DC-DC conversion on the AC voltage to obtain a DC voltage; and controlling the voltage regulator group to regulate the DC voltage to obtain the regulated voltage.

[0007] In the DC fan motor control method described above, the voltage signal set includes multiple square wave signals; the signal detection unit includes a voltage divider group, a filter group, and a zero-crossing detection group, which are connected sequentially; controlling the signal detection unit to acquire the voltage signal of the speed controller multiple times within a preset time period to obtain the voltage signal set includes: controlling the voltage divider group to acquire the voltage signal of the speed controller multiple times within a preset time period, and performing voltage divider processing on each voltage signal to obtain multiple low-voltage AC signals; controlling the filter group to filter each low-voltage AC signal to obtain multiple stable AC signals; and controlling the zero-crossing detection group to perform square wave conversion processing on each stable AC signal to obtain multiple square wave signals.

[0008] In the DC fan motor control method described above, determining the physical gear of the speed controller based on the voltage signal set includes: acquiring a preset gear identification rule; performing de-jittering and normalization processing on the voltage signal set using a gear identification algorithm, and determining a target voltage signal from the voltage signal set; and performing interval matching processing on the target voltage signal based on the gear identification rule to obtain the physical gear that matches the target voltage signal.

[0009] In the DC fan motor control method described above, confirming the PWM control signal corresponding to the physical gear position includes: obtaining a preset gear speed mapping table; performing a matching query based on the gear speed mapping table according to the physical gear position to obtain a target speed; and calculating the PWM control signal corresponding to the physical gear position based on the target speed.

[0010] The present invention also provides a DC fan motor control circuit, wherein the DC fan motor control circuit uses the DC fan motor control method described in any of the preceding claims to achieve operation control; the DC fan motor control circuit includes a control unit, a power supply unit, a signal detection unit, and a drive unit; one end of the power supply unit and one end of the signal detection unit are respectively connected to a speed controller, and the other end of the power supply unit and the other end of the signal detection unit are respectively connected to the control unit; the drive unit is connected to the DC fan motor; the power supply unit is used to convert the speed controller voltage of the speed controller into a stable voltage, and supply power to the control unit and the drive unit based on the stable voltage; the signal detection unit is used to collect the voltage signal of the speed controller multiple times within a preset time period to obtain a voltage signal set; the control unit is used to determine the physical gear of the speed controller based on the voltage signal set, confirm the PWM control signal corresponding to the physical gear, and generate an execution command based on the PWM control signal; the drive unit is used to drive the DC fan motor based on the execution command.

[0011] In the DC fan motor control circuit, the voltage signal set includes multiple square wave signals; the signal detection unit includes a voltage divider group, a filter group, and a zero-crossing detection group, which are connected in sequence; the voltage divider group is used to acquire the voltage signal of the speed controller multiple times within a preset time period, and perform voltage divider processing on each voltage signal to obtain multiple low-voltage AC signals; the filter group is used to filter each low-voltage AC signal to obtain multiple stable AC signals; the zero-crossing detection group is used to perform square wave conversion processing on each stable AC signal to obtain multiple square wave signals.

[0012] In the DC fan motor control circuit, the power supply unit includes an AC / DC conversion group and a voltage regulator group, which are connected together. The AC / DC conversion group is used to acquire the AC voltage of the speed controller and perform DC conversion processing on the AC voltage to obtain a DC voltage. The voltage regulator group is used to regulate the DC voltage to obtain a regulated voltage.

[0013] A third aspect of the present invention provides a DC fan motor control device, the DC fan motor control device comprising: a memory and at least one processor, the memory storing instructions; the at least one processor calling the instructions in the memory to cause the DC fan motor control device to execute the various steps of the DC fan motor control method described in any of the preceding claims.

[0014] A fourth aspect of the present invention provides a computer-readable storage medium storing instructions that, when executed by a processor, implement the steps of the DC fan motor control method described in any of the preceding claims.

[0015] In the technical solution of this invention, the DC fan motor control circuit includes a control unit, a power supply unit, a signal detection unit, and a drive unit. One end of the power supply unit and one end of the signal detection unit are respectively connected to a speed controller, and the other end of the power supply unit and the other end of the signal detection unit are respectively connected to the control unit. The control unit is connected to the drive unit, and the drive unit is connected to the DC fan motor. The method includes: after the control power supply unit converts the AC voltage of the speed controller into a stable voltage, the control signal detection unit collects the voltage signal of the speed controller multiple times within a preset time to obtain a voltage signal set. Then, based on the voltage signal set, the physical gear of the speed controller is determined. Next, the PWM control signal corresponding to the physical gear is confirmed, and an execution command is generated based on the PWM control signal. Finally, the control drive unit drives the DC fan motor based on the execution command. The aim is to accurately detect and analyze the AC voltage waveform signal from the traditional capacitor-type AC speed controller and map different gear signals to the target speed of the DC motor. Attached Figure Description

[0016] Figure 1 A logic flowchart of a DC fan motor control method provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of the structure of a DC fan motor control circuit provided in an embodiment of the present invention; Figure 3 A schematic diagram of a DC fan motor control circuit provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of the structure of a DC fan motor control device provided in an embodiment of the present invention.

[0017] Explanation of key component symbols: 100-Control unit, 110-Power supply unit, 120-Signal detection unit, 130-Drive unit. Detailed Implementation

[0018] This invention provides a DC fan motor control method, circuit, device, and storage medium. In this invention, the terms "first," "second," "third," "fourth," etc. (if present)," in the specification, claims, and accompanying drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments described herein can be implemented in a sequence other than that illustrated or described herein. Furthermore, the terms "comprising" or "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or device that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or devices.

[0019] For ease of understanding, the specific process of this embodiment of the invention is described below. The DC fan motor control circuit includes a control unit, a power supply unit, a signal detection unit, and a drive unit. One end of the power supply unit and one end of the signal detection unit are respectively connected to a speed controller. The other end of the power supply unit and the other end of the signal detection unit are respectively connected to the control unit. The control unit is connected to the drive unit, and the drive unit is connected to the DC fan motor. Please refer to [link to relevant documentation]. Figure 1 One embodiment of the DC fan motor control method in this invention includes: 101. After the power supply unit converts the AC voltage of the speed controller into a stable voltage, the signal detection unit is controlled to collect the voltage signal of the speed controller multiple times within a preset time period to obtain a voltage signal set; In this embodiment, after the control power supply unit converts the AC voltage of the speed controller into a stable voltage, the control signal detection unit collects the voltage signal of the speed controller multiple times within a preset time to obtain a voltage signal set. Specifically, the power supply unit is connected to the output terminal of the speed controller and adopts a wide-range input AC-DC conversion structure, which can convert the differentiated AC voltage output of each speed setting of the speed controller, and stably convert the AC voltage of tens to two hundred volts into DC voltage suitable for the operation of subsequent circuit modules. In particular, it provides a stable working power supply for the signal detection unit and the control unit, ensuring that each module can operate normally and stably.

[0020] After the power supply unit completes the conversion from AC voltage to stable DC voltage and achieves stable power supply, the signal detection unit starts its data acquisition. This unit, connected in parallel to the AC input of the power supply unit, captures the original AC voltage signal modulated by the speed controller. Within a preset time period (the preset time must be determined based on the speed controller's operating characteristics to ensure comprehensive capture of the speed controller's output voltage fluctuations and stability features), the unit continuously acquires the AC voltage signal from the speed controller multiple times through its integrated voltage divider network, filter circuit, and analog-to-digital conversion channel. This data is then integrated to form a voltage signal set containing multiple effective voltage signals, and the electrical characteristics representing different speed settings are extracted simultaneously. This well-planned timing of the power supply and signal detection units avoids signal distortion and excessive errors caused by unstable power supply. The voltage signal set formed by multiple acquisitions comprehensively reflects the characteristics of the speed controller's output voltage, providing sufficient and reliable data support for subsequent speed setting identification, thereby achieving accurate adaptation to existing capacitor-type speed controllers. It effectively solves the technical problem of incompatibility between existing DC fan controllers and traditional capacitor speed controllers, eliminating the need to replace existing wall-mounted speed control switches and wiring, reducing user upgrade and renovation costs, promoting the market replacement of traditional AC fans by DC brushless fans, improving the accuracy and stability of speed recognition, ensuring the reliability and smoothness of DC fan operation, and further leveraging the advantages of DC brushless fans such as high efficiency, low noise, and stepless speed regulation.

[0021] 102. Determine the physical gear of the speed controller based on the voltage signal set; In this embodiment, the control unit first performs in-depth analysis on the acquired voltage signal set. For multiple sets of effective voltage signals in the signal set, it extracts the core electrical characteristic quantities representing the speed controller's gear position and calculates the stable value of these characteristic quantities within one or more power frequency cycles. This eliminates random errors from single-sample acquisition and ensures that the characteristic quantities accurately reflect the speed controller's output state. The characteristic quantities may include effective voltage values, average values, phase offsets, or waveform distortion rates, all of which are key parameters for accurately distinguishing different gear positions. Their calculation process must follow strict signal processing logic to ensure the accuracy and reliability of the data.

[0022] The control unit has a pre-stored gear characteristic threshold table. This threshold table is based on preset electrical characteristic standards corresponding to different physical gears, covering the characteristic threshold range of each gear and the off gear, providing a clear comparison basis for gear determination. After completing the characteristic quantity calculation, the control unit compares the actually calculated characteristic quantity with the preset standards in the gear characteristic threshold table one by one. Through precise threshold matching, it determines the physical gear of the current speed controller and simultaneously identifies the off gear, ensuring no gear omission or misjudgment. This effectively solves the technical problem that existing DC fan controllers cannot correctly identify the gear of capacitor-type speed controllers, achieving deep compatibility with existing capacitor-type speed controllers.

[0023] 103. Confirm the PWM control signal corresponding to the physical gear position, and generate an execution command based on the PWM control signal; 104. Control the drive unit to drive the DC fan motor based on the execution command.

[0024] In this embodiment, after identifying the physical gear of the speed controller, the control unit calls an internally preset gear-speed mapping table to determine the PWM control signal corresponding to the physical gear. This mapping table is pre-calibrated based on the inherent characteristics, operating efficiency, and user preferences of the brushless DC motor. It can be set using linear or non-linear mapping relationships according to actual application needs, ensuring that the target speed corresponding to different physical gears conforms to the motor's operating rules while also meeting the user's differentiated needs for fan speed, achieving optimal matching between gear and speed. Furthermore, to adapt to unknown models of capacitor-type speed controllers, a self-learning mode can be added. During the process of the user sequentially switching each physical gear of the speed controller, including the off position, the control unit automatically collects and records the voltage signal characteristics corresponding to each gear, simultaneously establishing a gear-speed mapping table adapted to the current unknown model of capacitor-type speed controller. This table can be directly used for subsequent target speed determination and PWM control signal confirmation, eliminating the need for manual calibration of signal characteristics and speed mapping relationships, significantly improving the adaptability of the control unit. After determining the target speed corresponding to the current physical gear, the control unit calculates the PWM signal duty cycle adapted to the target speed based on the correspondence between the speed and the PWM control signal duty cycle. This confirms the corresponding PWM control signal. The duty cycle of the PWM control signal directly determines the output power of the motor drive module, and its magnitude is positively correlated with the motor speed. By precisely adjusting the duty cycle, precise control of the motor speed can be achieved. After confirming the PWM control signal, the control unit integrates the core parameters of the PWM control signal with relevant control requirements such as motor start-up timing and operation protection logic to generate standardized execution instructions. These instructions can be directly parsed and executed by the motor drive module, ensuring that the motor drive module can stably output drive signals to the brushless DC motor according to the preset speed requirements. Through precise confirmation of the PWM control signal and standardized generation of execution instructions, precise control of the motor speed is achieved, effectively avoiding problems such as speed fluctuations and uneven airflow, ensuring the smoothness and stability of the brushless DC fan operation.

[0025] In this embodiment of the invention, the power supply unit includes an AC / DC conversion group and a voltage regulator group, which are connected to each other. Controlling the power supply unit to convert the AC voltage of the speed controller into a stable voltage includes: controlling the AC / DC conversion group to acquire the AC voltage of the speed controller and performing DC-DC conversion on the AC voltage to obtain a DC voltage; and controlling the voltage regulator group to perform voltage regulation on the DC voltage to obtain the regulated voltage.

[0026] In this embodiment, the AC / DC converter is directly connected to the output terminal of the speed controller, which can acquire the differentiated AC voltage output of each speed controller position in real time. This AC voltage fluctuates over a wide range from tens to over two hundred volts due to the speed controller position switching. The AC / DC converter has a built-in wide-range input AC / DC conversion circuit, which can efficiently convert such fluctuating AC voltage. Through core operations such as rectification and inversion, it converts the sinusoidal AC voltage into a unidirectional DC voltage, completing the basic AC to DC conversion and providing a qualified initial DC signal for subsequent voltage regulation. Its conversion efficiency and input adaptation range directly determine the power supply section's ability to adapt to different speed controller positions. The voltage regulator is connected to the AC / DC converter and is used to regulate the DC voltage output by the AC / DC converter. Since the DC voltage has a certain voltage ripple and fluctuation, it cannot directly meet the power supply requirements of sensitive circuits such as the control unit and signal detection unit. In particular, the control unit has extremely high requirements for power supply stability. The voltage regulator performs ripple suppression, voltage calibration and stable output control on the DC voltage, effectively filtering out noise interference in the DC voltage and suppressing voltage fluctuations. Finally, it outputs a stable voltage of a fixed specification, usually 5V or 3.3V, which can directly provide a stable and clean operating voltage for subsequent circuit modules such as the control unit and signal detection unit. This ensures the stability of the operating parameters of each module circuit and avoids problems such as signal acquisition distortion, misjudgment of gear position recognition and abnormal control commands caused by unstable power supply.

[0027] In this embodiment of the invention, the voltage signal set includes multiple square wave signals; the signal detection unit includes a voltage divider group, a filter group, and a zero-crossing detection group, which are connected sequentially; controlling the signal detection unit to acquire the voltage signal of the speed controller multiple times within a preset time to obtain the voltage signal set includes: controlling the voltage divider group to acquire the voltage signal of the speed controller multiple times within a preset time, and performing voltage divider processing on each voltage signal to obtain multiple low-voltage AC signals; controlling the filter group to filter each low-voltage AC signal to obtain multiple stable AC signals; and controlling the zero-crossing detection group to perform square wave conversion processing on each stable AC signal to obtain multiple square wave signals.

[0028] In this embodiment, the signal detection unit is connected in parallel to the AC input terminal of the power supply unit. This connection method ensures direct capture of the original AC voltage signal modulated by the speed controller, avoiding the loss of key features such as phase and waveform distortion related to the gear position after the signal undergoes AC-DC conversion by the power supply unit. The voltage divider group is controlled to acquire the voltage signal of the speed controller multiple times within a preset time. The preset time setting needs to be combined with the working characteristics of the speed controller to ensure that the fluctuation pattern and stability characteristics of the output voltage of the speed controller can be fully captured. This voltage divider group can adapt to a wide range of AC voltages from tens to over two hundred volts output by the speed controller at each gear position. Through the internally integrated resistor network, each acquired AC voltage is proportionally divided to reduce the high-voltage AC signal to a low-voltage AC signal suitable for the operation of the filter group and zero-crossing detection group. This effectively avoids the high-voltage signal from damaging subsequent circuit modules and retains the voltage amplitude, phase and other features related to the gear position in the original AC signal, ensuring the basic reliability of signal conditioning. After multiple acquisitions, multiple sets of low-voltage AC signals are formed. Subsequently, the control filter group filters each low-voltage AC signal. Through circuit structures such as RC filters, it filters out grid noise, transient interference generated by speed governor gear switching, and other useless signal components, suppresses fluctuations and noise in the signal, and eliminates the influence of interference factors on signal characteristics. This ensures that each stable AC signal after filtering can truly reflect the output state of the speed governor at the current gear, laying the foundation for subsequent square wave conversion and feature extraction. Finally, the zero-crossing detection group performs square wave conversion processing on each stable AC signal. Based on the working principle of zero-crossing trigger level switching, the zero-crossing detection group quickly triggers level switching when the stable AC signal passes through the zero point, that is, the critical node where the voltage changes from positive to negative and from negative to positive. This converts the continuously changing analog AC signal into a square wave signal with alternating high and low levels. The rising and falling edges of the square wave signal precisely correspond to the zero-crossing point of the stable AC signal, which can effectively capture the phase information that characterizes the gear difference of the speed controller. At the same time, as a digital signal, the square wave signal can be directly recognized and processed by the control unit. Finally, it is integrated to form a voltage signal set containing multiple square wave signals, realizing the conversion of analog signals to digital signals and solving the technical problem that the control unit cannot directly recognize analog AC signals.

[0029] In this embodiment of the invention, determining the physical gear of the speed controller based on the voltage signal set includes: acquiring a preset gear identification rule; performing de-jittering and normalization processing on the voltage signal set using a gear identification algorithm, and determining a target voltage signal from the voltage signal set; and performing interval matching processing on the target voltage signal based on the gear identification rule to obtain the physical gear that matches the target voltage signal.

[0030] In this embodiment, the preset gear position recognition rules need to be formulated based on the electrical characteristics of the capacitor speed controller and the adaptation requirements of the DC fan motor. This covers the signal characteristic threshold ranges corresponding to each physical gear and the off position, while also being compatible with various recognition logics such as time-domain analysis, frequency-domain analysis, time-frequency combined analysis, and machine learning, providing a clear and flexible basis for accurate gear position determination. The gear position recognition algorithm adopted is based on time-domain analysis, taking into account both anti-interference and jitter reduction capabilities. Its core logic is to accurately extract key information representing the gear position by calculating signal characteristic values ​​within one or more power frequency cycles. During algorithm execution, the voltage signal set is first subjected to jitter reduction processing. Multiple continuously acquired square wave signals are smoothed and filtered using the moving average method to eliminate abnormal signals caused by power grid noise, poor mechanical contact of the speed controller, and transient circuit interference. This eliminates judgment errors caused by signal jitter, ensures the stability and authenticity of signal data, and avoids misjudgments caused by transient interference. Following this, normalization is performed to map the characteristic values ​​of square wave signals, which exhibit amplitude or period differences under different acquisition scenarios, to a unified data range. This eliminates inconsistencies in signal characteristic scale caused by subtle differences in speed controller models and deviations in acquisition circuit parameters, thus standardizing the signal data. After jitter reduction and normalization, the algorithm calculates characteristic values ​​based on one or more power frequency cycles, focusing on extracting core characteristic quantities such as the effective voltage value and average value corresponding to the square wave signal. Combining the phase information corresponding to the rising and falling edges of the square wave, it filters characteristic data from the voltage signal set that can completely and accurately reflect the current operating state of the speed controller. This determines the target voltage signal, ensuring that the target voltage signal can fully carry the core electrical characteristics of the current speed controller gear and avoids interference from invalid signals. Subsequently, based on preset gear identification rules, the characteristic value corresponding to the target voltage signal is compared one by one with the threshold ranges of each gear and the off gear in the rules. When the characteristic value falls into a certain preset threshold range, the accurate determination of the current physical gear of the speed controller can be completed, ensuring accurate identification of all physical gears and the off gear without omissions or misjudgments.

[0031] In addition, it is understandable that for diverse and non-standard capacitor speed controllers, a simple classifier can be used to build a machine learning model. First, the model is trained offline using waveform data from multiple sets of different non-standard speed controllers. The gear characteristics of the non-standard speed controllers are incorporated into the model recognition system. Then, based on the trained model, the pre-processed voltage signal is identified online, replacing the traditional interval matching method to determine the gear of the non-standard speed controller and adapting to the differences in signal characteristics of non-standard speed controllers.

[0032] In this embodiment of the invention, confirming the PWM control signal corresponding to the physical gear position includes: obtaining a preset gear-speed mapping table; performing a matching query based on the gear-speed mapping table according to the physical gear position to obtain a target speed; and calculating the PWM control signal corresponding to the physical gear position based on the target speed.

[0033] In this embodiment, the preset speed-gear mapping table is pre-calibrated based on the inherent characteristics, operating efficiency, and user preferences of the brushless DC motor. It can be set using linear or non-linear mapping relationships according to actual application needs, ensuring that the target speed corresponding to different physical gears conforms to the motor's operating characteristics while also meeting the user's differentiated requirements for fan speed, achieving optimal matching between gear and speed. Furthermore, to adapt to unknown capacitor speed controller models, a self-learning mode can be added. During the user's sequential switching of each physical gear of the speed controller, including the off position, the control unit automatically collects and records the voltage signal characteristics corresponding to each gear, simultaneously establishing a speed-gear mapping table adapted to the current unknown capacitor speed controller model. This table can be directly used for subsequent target speed determination and PWM control signal confirmation, eliminating the need for manual calibration of signal characteristics and speed mapping relationships, significantly improving the control unit's adaptability.

[0034] After identifying the physical gear position of the speed controller, a matching query is performed in a preset gear-speed mapping table based on this physical gear position. Through gear matching, the target speed corresponding to the current physical gear position is determined. To achieve a high-quality conversion from stepped gear position signals to stepless smooth speed output, after the matching query is completed, a closed-loop motor control algorithm, such as the PID algorithm, is used to dynamically optimize and adjust the target speed. This effectively eliminates the speed abrupt changes caused by traditional stepped speed regulation, allowing the motor speed to transition smoothly and avoiding issues such as speed fluctuations and uneven wind speed that affect the user experience. Based on the optimized target speed, and considering the inherent correlation between speed and PWM control signal duty cycle, the PID algorithm calculates the PWM signal duty cycle adapted to the target speed, thereby generating a PWM control signal corresponding to the current physical gear position. The duty cycle of the PWM control signal directly determines the output power of the motor drive unit, and its magnitude is positively correlated with the motor speed. By accurately setting the duty cycle, precise control of the motor speed can be achieved, ensuring that the motor speed stably matches the target speed. This effectively solves the technical problems of incompatibility between existing DC fan controllers and traditional capacitor-type speed controllers, as well as the high cost of upgrades and modifications.

[0035] Please see Figure 2 and Figure 3The present invention also provides a DC fan motor control circuit, wherein the DC fan motor control circuit uses the DC fan motor control method described in any of the preceding claims to achieve operation control; the DC fan motor control circuit includes a control unit 100, a power supply unit 110, a signal detection unit 120, and a drive unit 130, wherein one end of the power supply unit 110 and one end of the signal detection unit 120 are respectively connected to a speed controller, the other end of the power supply unit 110 and the other end of the signal detection unit 120 are respectively connected to the control unit 100, and the drive unit 130 is connected to the DC fan motor; The power supply unit 110 is used to convert the speed regulator voltage of the speed regulator into a stable voltage, and to supply power to the control unit 100 and the drive unit 130 based on the stable voltage; the signal detection unit 120 is used to collect the voltage signal of the speed regulator multiple times within a preset time period to obtain a voltage signal set; the control unit 100 is used to determine the physical gear of the speed regulator based on the voltage signal set, confirm the PWM control signal corresponding to the physical gear, and generate an execution command based on the PWM control signal; the drive unit 130 is used to drive the DC fan motor based on the execution command.

[0036] In this embodiment, the DC fan motor control circuit includes a control unit 100, a power supply unit 110, a signal detection unit 120, and a drive unit 130. These parts are connected by circuitry to form a complete control system, ensuring that the DC fan motor can respond to the speed regulator's gear adjustment and achieve stable and efficient operation. One end of the power supply unit 110 and one end of the signal detection unit 120 are respectively connected to the speed regulator, while the other ends of the power supply unit 110 and the signal detection unit 120 are respectively connected to the control unit 100. The drive unit 130 is connected to the DC fan motor. This connection method not only ensures stable transmission of signals and electrical energy between modules but also achieves accurate acquisition of speed regulator signals and efficient execution of motor drive, which is the foundation for the normal operation of the entire control circuit.

[0037] The core function of the power supply unit 110 is to convert the speed controller voltage output by the speed controller into a stable voltage, and then use this stable voltage to power the control unit 100 and the drive unit 130. Connected to the output of the speed controller, it uses a wide-range input AC-DC conversion circuit, which can adapt to the wide range of AC voltages from tens to over two hundred volts output by the speed controller at various speed settings. Through the coordinated work of AC-DC conversion and voltage regulation, it converts the fluctuating AC speed controller voltage into a stable DC voltage of a fixed specification, usually 5V or 3.3V. This stable voltage not only provides a clean and reliable operating power supply for the control unit 100, ensuring the stable operation of the control unit 100 algorithm, but also provides sufficient power to the drive unit 130, ensuring that the drive unit 130 can output sufficient drive power to meet the power requirements of the DC fan motor at different speeds, and avoiding problems such as abnormal operation of various modules and fluctuations in motor speed due to unstable power supply.

[0038] The signal detection unit 120 is used to collect the voltage signal of the speed controller multiple times within a preset time period to obtain a voltage signal set. It synchronously extracts the electrical characteristic quantities that represent the current gear position, including the effective value and average value of the voltage corresponding to different gear positions, the waveform peak value and distortion rate difference caused by different capacitors in series, and the voltage phase change obtained by zero-crossing detection, so as to provide comprehensive and reliable data support for the gear position recognition of the control unit 100.

[0039] The control unit 100 integrates a main control unit that receives voltage signal sets transmitted by the signal detection unit 120. Based on these signal sets, it determines the physical gear position of the speed controller. Specifically, this is achieved by executing a gear position recognition algorithm. The algorithm analyzes and processes the square wave signal in the voltage signal set, calculates the signal characteristic values ​​within one or more power frequency cycles, and compares them one by one with an internally stored gear position characteristic threshold table. Simultaneously, it incorporates anti-interference and de-jitter processing to effectively eliminate abnormal signals and suppress interference, ensuring accurate determination of the current physical gear position of the speed controller, including the off position, avoiding misjudgments or omissions. After completing gear position recognition, the control unit 100 further executes speed mapping and control logic, queries an internally preset gear-speed mapping table, and determines the target speed corresponding to the current physical gear position. This mapping relationship can be flexibly set linearly or nonlinearly according to the inherent characteristics of the brushless DC motor and user preferences, balancing motor operating efficiency and user experience. Subsequently, the control unit 100 generates a corresponding PWM control signal by executing a motor control algorithm. This algorithm employs a PID closed-loop control strategy, combining the Hall sensor signal or back EMF signal fed back from the motor to detect the actual motor speed in real time, calculate the deviation between the actual speed and the target speed, and dynamically adjust the duty cycle of the PWM control signal. This ensures that the actual motor speed accurately tracks the target speed, while simultaneously achieving smooth motor start-stop and gear shift transitions, avoiding noise, vibration, and other problems caused by sudden speed changes. Finally, based on the optimized PWM control signal, the control unit 100 integrates the timing, protection, and other relevant parameters required for motor drive, generates standardized execution instructions, and transmits them to the drive unit 130.

[0040] Further, please refer to Figure 2 and Figure 3 The voltage signal set includes multiple square wave signals; the signal detection unit 120 includes a voltage divider group, a filter group, and a zero-crossing detection group, which are connected in sequence; the voltage divider group is used to acquire the voltage signal of the speed controller multiple times within a preset time period, and perform voltage divider processing on each voltage signal to obtain multiple low-voltage AC signals; the filter group is used to filter each low-voltage AC signal to obtain multiple stable AC signals; the zero-crossing detection group is used to perform square wave conversion processing on each stable AC signal to obtain multiple square wave signals.

[0041] Further, please refer to Figure 2 and Figure 3 The power supply unit 110 includes an AC / DC conversion group and a voltage regulator group, which are connected to each other. The AC / DC conversion group is used to acquire the AC voltage of the speed controller and perform DC conversion processing on the AC voltage to obtain a DC voltage. The voltage regulator group is used to perform voltage regulation processing on the DC voltage to obtain a regulated voltage.

[0042] In this embodiment, the DC fan motor control circuit also includes LED indicator lights and a buzzer, which are used to provide intuitive prompts of status information through dual feedback of light and sound when the control unit identifies the physical gear of the speed controller and the operating fault status of various circuits. This provides clear information reference for user operation and fault diagnosis, and improves the status interaction function of the control circuit.

[0043] Figure 4 This is a schematic diagram of the structure of a DC fan motor control device 400 provided in an embodiment of the present invention. The DC fan motor control device 400 can vary significantly due to different configurations or performance characteristics. It may include one or more central processing units (CPUs) 410 (e.g., one or more processors) and a memory 420, and one or more storage media 430 (e.g., one or more mass storage devices) storing application programs 433 or data 432. The memory 420 and storage media 430 can be temporary or persistent storage. The program stored in the storage media 430 may include one or more modules (not shown in the diagram), each module including a series of instruction operations on the DC fan motor control device 400. Furthermore, the processor 410 may be configured to communicate with the storage media 430 and execute the series of instruction operations in the storage media 430 on the DC fan motor control device 400 to implement the steps of the DC fan motor control method provided in the above-described method embodiments.

[0044] The DC fan motor control device 400 may also include one or more power supplies 440, one or more wired or wireless network interfaces 450, one or more input / output interfaces 460, and / or one or more operating systems 431, such as Windows Server, Mac OS X, Unix, Linux, FreeBSD, etc. Those skilled in the art will understand that... Figure 4 The structure of the DC fan motor control device shown does not constitute a limitation on the DC fan motor control device, and may include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0045] The present invention also provides a computer-readable storage medium, which can be a non-volatile computer-readable storage medium or a volatile computer-readable storage medium, wherein the computer-readable storage medium stores instructions that, when executed on a computer, cause the computer to perform the steps of a DC fan motor control method.

[0046] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working process of the system, device, or unit described above can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0047] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0048] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A DC fan motor control method, characterized in that, The DC fan motor control circuit includes a control unit, a power supply unit, a signal detection unit, and a drive unit. One end of the power supply unit and one end of the signal detection unit are respectively connected to a speed controller. The other end of the power supply unit and the other end of the signal detection unit are respectively connected to the control unit. The control unit is connected to the drive unit, and the drive unit is connected to the DC fan motor. The method includes: After the power supply unit converts the AC voltage of the speed controller into a stable voltage, the signal detection unit is controlled to collect the voltage signal of the speed controller multiple times within a preset time period to obtain a voltage signal set. The physical gear of the speed controller is determined based on the voltage signal set; Identify the PWM control signal corresponding to the physical gear position, and generate an execution command based on the PWM control signal; The drive unit is controlled to drive the DC fan motor based on the executed command.

2. The DC fan motor control method according to claim 1, characterized in that, The power supply unit includes an AC / DC converter and a voltage regulator, which are connected together; controlling the power supply unit to convert the AC voltage of the speed controller into a stable voltage includes: The AC / DC converter group is controlled to acquire the AC voltage of the speed controller, and the AC voltage is converted into DC voltage. The voltage regulator is controlled to regulate the DC voltage to obtain the regulated voltage.

3. The DC fan motor control method according to claim 1, characterized in that, The voltage signal set includes multiple square wave signals; the signal detection unit includes a voltage divider group, a filter group, and a zero-crossing detection group, which are connected in sequence. The control signal detection unit acquires the voltage signal of the speed controller multiple times within a preset time period to obtain a voltage signal set, including: The voltage divider group is controlled to collect the voltage signal of the speed controller multiple times within a preset time period, and each voltage signal is divided to obtain multiple low-voltage AC signals. The filter group is controlled to filter each of the low-voltage AC signals to obtain multiple stable AC signals; The zero-crossing detection group is controlled to perform square wave conversion processing on each of the stable AC signals to obtain multiple square wave signals.

4. The DC fan motor control method according to claim 1, characterized in that, The step of determining the physical gear of the speed controller based on the voltage signal set includes: Obtain the preset gear recognition rules; A gear position recognition algorithm is used to perform de-jitter processing and normalization processing on the voltage signal set, and the target voltage signal is determined from the voltage signal set; Based on the gear identification rule, the target voltage signal is subjected to interval matching processing to obtain the physical gear that matches the target voltage signal.

5. The DC fan motor control method according to claim 1, characterized in that, The confirmation of the PWM control signal corresponding to the physical gear position includes: Obtain the preset gear speed mapping table; Based on the gear-speed mapping table, a matching query is performed according to the physical gear to obtain the target speed, and the PWM control signal corresponding to the physical gear is calculated based on the target speed.

6. A DC fan motor control circuit, wherein the DC fan motor control circuit uses the DC fan motor control method as described in any one of claims 1-5 to achieve operation control; the DC fan motor control circuit includes a control unit, a power supply unit, a signal detection unit, and a drive unit; one end of the power supply unit and one end of the signal detection unit are respectively connected to a speed controller, the other end of the power supply unit and the other end of the signal detection unit are respectively connected to the control unit, and the drive unit is connected to the DC fan motor; the power supply unit is used to convert the speed controller voltage of the speed controller into a stable voltage, and supply power to the control unit and the drive unit based on the stable voltage; the signal detection unit is used to collect the voltage signal of the speed controller multiple times within a preset time period to obtain a voltage signal set; the control unit is used to determine the physical gear of the speed controller based on the voltage signal set, confirm the PWM control signal corresponding to the physical gear, and generate an execution command based on the PWM control signal; the drive unit is used to drive the DC fan motor based on the execution command.

7. The DC fan motor control circuit according to claim 6, characterized in that, The voltage signal set includes multiple square wave signals; the signal detection unit includes a voltage divider group, a filter group, and a zero-crossing detection group, which are connected in sequence; the voltage divider group is used to acquire the voltage signal of the speed controller multiple times within a preset time period, and perform voltage divider processing on each voltage signal to obtain multiple low-voltage AC signals; the filter group is used to filter each low-voltage AC signal to obtain multiple stable AC signals; the zero-crossing detection group is used to perform square wave conversion processing on each stable AC signal to obtain multiple square wave signals.

8. The DC fan motor control circuit according to claim 6, characterized in that, The power supply unit includes an AC / DC conversion group and a voltage regulator group, which are connected to each other. The AC / DC conversion group is used to acquire the AC voltage of the speed controller and perform DC conversion processing on the AC voltage to obtain a DC voltage. The voltage regulator group is used to perform voltage regulation processing on the DC voltage to obtain a regulated voltage.

9. A DC fan motor control device, characterized in that, The DC fan motor control device includes: a memory and at least one processor, wherein the memory stores instructions; At least one of the processors invokes the instructions in the memory to cause the DC fan motor control device to perform the steps of the DC fan motor control method as described in any one of claims 1-5.

10. A computer-readable storage medium storing instructions thereon, characterized in that, When the instructions are executed by the processor, they implement the various steps of the DC fan motor control method as described in any one of claims 1-5.

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