Fan driven by circumferentially-distributed multi-section type arc motor and control method of fan

Abstract

The invention provides a fan driven by a circumferentially-distributed multi-section type arc motor. The fan comprises an outer frame, a center shaft, an impeller and a multi-section type arc motor system. The central shaft is fixedly mounted on the outer frame; the impeller is rotatably arranged on the central shaft in a sleeving manner through a bearing; the multi-section type arc motor system comprises a plurality of sections of arc-shaped permanent magnet units which are fixedly arranged on the outer periphery of the impeller in the circumferential direction and jointly form a rotor of the motor; the multiple sections of arc-shaped armature winding units are fixedly arranged on the inner side of the outer frame in the circumferential direction and correspond to the permanent magnet units in position, and the multiple sections of arc-shaped armature winding units and the permanent magnet units jointly form a stator of the motor; and the motor driver is integrated in the outer frame, is electrically connected with each armature winding unit, and is used for controlling each section of arc motor to cooperatively work so as to drive the impeller to rotate. The fan is good in heat dissipation effect, high in torque and high in efficiency.

Description

Technical Field

[0001] This application relates to the field of fan and motor technology, and particularly to a fan structure and control method driven by a circumferentially distributed multi-segment circular arc motor. This invention is applicable to various scenarios requiring efficient, compact, and reliable fans, such as server cooling, home appliances, automotive cooling, and aerospace environmental control systems. Background Technology

[0002] Traditional fans typically employ a central motor that drives the impeller via a shaft system. This design suffers from problems such as a large hub ratio, low ventilation efficiency, difficulty in motor heat dissipation, and long axial dimensions. To address these issues, shaftless fan designs have emerged in the current technology, where the drive motor is positioned on the outer periphery of the impeller.

[0003] However, shaftless fans typically employ an integrated external rotor motor structure, with its stator windings arranged in a continuous ring, making manufacturing and maintenance inconvenient. Furthermore, the impeller relies entirely on a single-sided cantilever bearing support, placing high demands on the bearings and posing significant stability challenges at high speeds. In addition, the integrated design of the motor's magnetic circuit and structure limits the optimization space for heat dissipation and control. For example, an integrated motor requires complete replacement in case of failure, resulting in high costs; and the long heat dissipation path can easily lead to overheating of the windings, affecting its lifespan.

[0004] Therefore, there is an urgent need for a new type of fan structure that can balance high rigidity, high efficiency, easy maintenance, and good heat dissipation. Summary of the Invention

[0005] In view of the above problems, this application provides a fan driven by a circumferentially distributed multi-segment circular arc motor to solve the above technical problems.

[0006] This application provides a fan driven by a circumferentially distributed multi-segment circular arc motor, comprising: an outer frame, a central shaft, an impeller, and a multi-segment circular arc motor system; the central shaft is fixedly mounted on the outer frame; the impeller is rotatably mounted on the central shaft via bearings; the multi-segment circular arc motor system comprises: multiple segments of circular arc-shaped permanent magnet units, fixedly arranged circumferentially on the outer periphery of the impeller, collectively forming the motor's mover; multiple segments of circular arc-shaped armature winding units, fixedly arranged circumferentially on the inner side of the outer frame, corresponding to the positions of the permanent magnet units, collectively forming the motor's stator; a motor driver, integrated within the outer frame and electrically connected to each of the armature winding units, used to control the coordinated operation of each segment of the circular arc motor to drive the impeller to rotate; the motor driver is configured to implement unbalance compensation control on each segment of the circular arc-shaped armature winding units to suppress the vibration of the impeller.

[0007] In some embodiments, at least one pair of bearings are provided between the central shaft and the impeller.

[0008] In some embodiments, the central angle corresponding to each arc-shaped permanent magnet unit and the arc-shaped armature winding unit is less than 180°.

[0009] In some embodiments, the number of the multiple arc-shaped permanent magnet units is 1 to 8, with gaps between each segment.

[0010] In some embodiments, the motor driver is configured to provide phase-synchronized and current-independently controllable drive signals to each segment of the arc-shaped armature winding unit.

[0011] In some embodiments, the outer surface of the outer frame is provided with heat dissipation fins.

[0012] In some embodiments, the power devices of the motor driver are thermally connected to the external frame.

[0013] In some embodiments, the central flow channel region of the impeller is not obstructed by a motor structure.

[0014] In some embodiments, the multi-segment arc-shaped armature winding unit is wound using a concentrated winding method.

[0015] In some embodiments, the output of a particular arc-shaped armature winding unit is compensated and adjusted based on the impeller vibration or position feedback to achieve vibration suppression or torque fluctuation smoothing.

[0016] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit the disclosure of this application. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 A schematic diagram of a fan driven by a circumferentially distributed multi-segment circular arc motor is shown.

[0019] Figure 2 A front structural schematic diagram of a fan driven by a circumferentially distributed multi-segment circular arc motor is shown.

[0020] Figure 3 A side cross-sectional view of a fan driven by a circumferentially distributed multi-segment circular arc motor is shown.

[0021] Figure 4A schematic diagram of the rear structure of a fan driven by a circumferentially distributed multi-segment circular arc motor is shown. Detailed Implementation

[0022] The embodiments of this application are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote 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 this application, and should not be construed as limiting this application.

[0023] To enable those skilled in the art to better understand the solutions of this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0024] In the embodiments of this application, it should be noted that, in this document, relational terms such as first and second are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations.

[0025] Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one…" does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0026] In the description of the embodiments of this application, the words "example" or "for example" are used to indicate exemplification, illustration, or description. Any embodiment or design described as "example" or "for example" in the embodiments of this application is not to be construed as being more preferred or having more advantages than another embodiment or design. The use of the words "example" or "for example" is intended to present relative concepts in a clear manner.

[0027] In addition, "multiple" in the embodiments of this application refers to two or more. Therefore, "multiple" can also be understood as "at least two" in the embodiments of this application. "At least one" can be understood as one or more, such as one, two or more. For example, including at least one means including one, two or more and is not limited to which ones are included. For example, including at least one of A, B and C, then it can be A, B, C, A and B, A and C, B and C, or A and B and C.

[0028] It should be noted that in the embodiments of this application, "and / or" describes the relationship between associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. In addition, the character " / ", unless otherwise specified, generally indicates that the associated objects before and after it are in an "or" relationship.

[0029] It should be noted that in the embodiments of this application, "connection" can be understood as electrical connection. The connection between two electrical components can be a direct or indirect connection between the two electrical components. For example, the connection between A and B can be a direct connection between A and B, or an indirect connection between A and B through one or more other electrical components.

[0030] This application provides a fan 11 driven by a circumferentially distributed multi-segment circular arc motor, wherein the fan is an axial flow fan or a centrifugal fan. The fan includes an outer frame 1, a central shaft 2, an impeller 3, and a multi-segment circular arc motor system 12.

[0031] The outer frame 1 serves as the main support structure for the fan, manufactured using die-cast aluminum alloy or high thermal conductivity composite materials (such as thermally conductive plastics), with heat dissipation fins 9 on its outer surface. The heat dissipation fins 9 are evenly distributed circumferentially, with a height of 5-20mm and a thickness of 1-3mm to maximize the heat dissipation area. The overall dimensions of the outer frame 1 can be adjusted according to the fan power; for example, for an axial flow fan with a diameter of 200mm, the wall thickness of the outer frame 1 is 3-5mm to ensure structural strength and thermal conductivity. A temperature sensor 10 can be installed on the outer frame 1 to monitor the temperature of the motor driver 7.

[0032] The central shaft 2 is fixed to the outer frame 1 by supports at both ends. The central shaft 2 is made of stainless steel or high-strength alloy steel, and its diameter ranges from 10-50mm, depending on the fan load. The central shaft 2 is fixed to the outer frame 1 by bolting or welding to ensure rigidity.

[0033] At least one pair of bearings 4 are provided between the impeller 3 and the central shaft 2, allowing it to rotate around the shaft. Specifically, the impeller 3 is mounted on the central shaft 2 via two sets of angular contact ball bearings 4. The impeller 3 is made of lightweight materials such as aluminum alloy or carbon fiber composite material, with 5-12 blades to achieve efficient airflow. The central flow channel 8 of the impeller 3 is free from any motor structure obstruction, achieving a minimum hub ratio, for example, a hub ratio (the ratio of hub diameter to impeller outer diameter) of less than 0.3, thereby minimizing airflow resistance and improving ventilation efficiency. The bearings 4 are preferably angular contact ball bearings, but can also be replaced with deep groove ball bearings or magnetic levitation bearings to adapt to different speed and precision requirements. The bearings 4 are installed at both ends of the impeller 3, forming a double-support structure to avoid cantilever problems. The bearings 4 are angular contact ball bearings, deep groove ball bearings, or magnetic levitation bearings.

[0034] The multi-segment circular arc motor system 12 includes a multi-segment circular arc permanent magnet unit 5, a multi-segment circular arc armature winding unit 6, and a motor driver 7.

[0035] Arc-shaped permanent magnet units 5 are evenly arranged circumferentially on the outer edge of the impeller 3, collectively forming the mover of the motor. The arc-shaped permanent magnet units 5 use neodymium iron boron (NdFeB) or samarium cobalt (SmCo) permanent magnet materials, with N / S poles arranged alternately. The central angle of each arc-shaped permanent magnet unit 5 is less than 180°, for example, 60°-120°, preferably 90°, and the number of segments is 1-8 (e.g., 4 segments). A gap of 1-5mm is left between each segment to accommodate thermal expansion and facilitate installation. The permanent magnet units 5 are fixed to the impeller 3 by adhesive bonding or mechanical snap-fit.

[0036] An arc-shaped armature winding unit 6 is fixedly mounted circumferentially inside the outer frame 1, corresponding to the position of the arc-shaped permanent magnet unit 5, together forming the stator of the motor. Each arc-shaped armature winding unit 6 includes an arc-shaped iron core and a concentrated winding, forming an effective magnetic circuit coupling with the arc-shaped permanent magnet unit 5. The central angle of the arc-shaped armature winding unit 6 is less than 180°, for example, it can be 60°-120°, preferably 90°. The arc-shaped iron core is made of laminated silicon steel sheets, and the concentrated winding is made of copper wire with 10-50 turns, specifically designed according to the motor parameters. The air gap between the armature winding unit 6 and the permanent magnet unit 5 is 0.5-2mm to ensure efficient magnetic circuit coupling. Each armature winding unit 6 is fixed to the outer frame 1 with screws, and the gap is filled with thermally conductive adhesive to enhance heat dissipation.

[0037] The motor driver 7 is integrated within the external frame 1, specifically, it is mounted within the internal cavity of the frame 1. It is electrically connected to each of the arc-shaped armature winding units 6 to control the coordinated operation of each arc-shaped motor segment to drive the impeller rotation. The motor driver 7 is configured to implement unbalance compensation control for each arc-shaped armature winding unit 6 to suppress impeller vibration. The motor driver 7 is configured to provide phase-synchronized and independently controllable drive signals to each arc-shaped armature winding unit 6. The power devices (such as IGBTs or MOSFETs) of the motor driver 7 are in close contact with the thermally conductive substrate of the external frame 1, achieving thermal connection through a thermal interface material (such as thermal grease). The motor driver 7 includes a multi-channel inverter circuit, a microprocessor (such as a DSP or ARM), and a sensor interface. The motor driver 7 is connected to each arc-shaped armature winding unit 6 through multiple output ports, each output of which can independently control current and phase. The motor driver 7 can also be configured to perform overheating de-load or protection operations based on feedback signals from the temperature sensor 10.

[0038] The fan 11 also includes a position detection element for detecting the rotational position or speed of the impeller 3 and feeding it back to the motor driver 7 to achieve closed-loop control.

[0039] This application also provides a method for controlling the above-mentioned fan, the specific steps of which are as follows: System initialization: After power-on, the motor driver 7 performs a self-test, including sensor calibration and inter-segment communication synchronization.

[0040] Receive external control commands: Commands come from the host computer or user interface, including speed setpoints (such as 1000-5000 RPM) or torque commands.

[0041] Generating Multiple Drive Signals: The microprocessor of the motor driver 7 generates multiple synchronous and independently controllable drive signals according to instructions and through control algorithms. The control algorithms include: a phase synchronization module: ensuring the current phase of each armature winding unit 6 is consistent, and adjusting in real time based on the impeller 3's rotational position feedback from the position sensor. A current independent control module: independently adjusting the current amplitude of each winding segment according to load requirements, ranging from 0-10A with an accuracy of ±1%. For example, during startup, all segments output maximum current to provide high starting torque; during steady-state operation, adjusting the current of specific segments based on vibration feedback to suppress vibration. A fault-tolerant control module: if a motor segment fails (e.g., a winding short circuit), the system detects the anomaly, automatically reducing the current of the faulty segment to zero and increasing the current of other segments to maintain total output torque. A thermal management module: based on feedback from the temperature sensor 10 (temperature range -40°C to 150°C), if the temperature exceeds a threshold (e.g., 80°C), an overheating load reduction operation is performed, proportionally reducing the output power.

[0042] Apply drive signals: Convert each drive signal into AC power through the inverter circuit and apply it to the corresponding armature winding unit 6 to drive the impeller 3 to rotate.

[0043] Closed-loop feedback: The rotational speed and position of impeller 3 are monitored in real time by a position sensor and fed back to the motor driver 7 to achieve closed-loop control. Simultaneously, data from vibration sensors (such as accelerometers) is used for torque fluctuation compensation; by adjusting the current phase in a specific segment, the output torque is smoothed. Based on the vibration or position feedback of impeller 3, the output of a specific arc-shaped armature winding unit 6 is compensated and adjusted to achieve vibration suppression or torque fluctuation smoothing. This method achieves efficient and stable operation with noise levels below 50dB, making it suitable for high-precision environments.

[0044] The fans described in this application can be applied to a variety of devices, including server cooling fans, automotive cooling fans, and aerospace environmental control systems. The server cooling fan has a 100mm diameter, four-segment design, and a rotational speed of 3000 RPM, achieving low noise and efficient cooling through independent control. The automotive cooling fan has a 300mm diameter, six-segment design, a waterproof design, and fault-tolerant control to ensure reliability. The aerospace environmental control system fan has a 500mm diameter, eight-segment design, uses magnetic levitation bearings and high-temperature materials, and is adapted to extreme environments.

[0045] This application solves the key technical bottlenecks of existing wind turbines through modular design and advanced control, and has the advantages of high reliability, easy maintenance and low cost, making it suitable for large-scale production.

[0046] Compared to existing technologies, the beneficial effects of this application include: High structural rigidity: The impeller is mainly supported by the central shaft and combined with the multi-segment motor drive on the outer periphery to form a hybrid structure of "central positioning + circumferential drive", which greatly improves the system's resistance to shock and vibration and is suitable for high-speed and high-load conditions.

[0047] High torque and high efficiency: The motor stator and rotor are arranged at the maximum diameter of the impeller, resulting in a large lever arm and high torque density; the parallel drive of multiple arc motors results in a large total output torque and a significant increase in power density.

[0048] Excellent heat dissipation: The armature winding unit is directly installed in the external frame, with a large heat dissipation area and low thermal resistance; the motor driver is thermally connected to the frame and can be cooled by the airflow of the fan itself, without the need for an external cooling device.

[0049] Modular and fault-tolerant: Multi-segment circular arc motors can be manufactured, tested and replaced independently, making maintenance convenient; when a segment of the motor fails, the system can achieve fault-tolerant operation by adjusting the output of the remaining segments, resulting in high reliability.

[0050] Flexible control: Independent current and phase control can be implemented for each section of the motor to achieve advanced control functions such as vibration suppression and torque fluctuation compensation, thereby improving operational stability and noise performance.

[0051] The above are merely preferred embodiments of this application and are not intended to limit this application in any way. Although this application has disclosed preferred embodiments as above, it is not intended to limit this application. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the technical solution of this application. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of this application without departing from the scope of the technical solution of this application shall still fall within the scope of the technical solution of this application.

Claims

1. A fan driven by a circumferentially distributed multi-segment circular arc motor, characterized in that, Includes an external frame, central shaft, impeller, and multi-segment circular arc motor system; The central shaft is fixedly installed on the external frame; The impeller is rotatably mounted on the central shaft via bearings; The multi-segment circular arc motor system includes: Multiple arc-shaped permanent magnet units are fixedly arranged circumferentially on the outer periphery of the impeller, together forming the motor's mover; Multiple arc-shaped armature winding units are fixedly disposed circumferentially on the inner side of the outer frame and connected to the permanent magnet unit. Their corresponding positions together constitute the stator of the motor; A motor driver, integrated within the external frame and electrically connected to each of the armature winding units, is used to control the coordinated operation of each segment of the arc-shaped motor to drive the impeller to rotate; the motor driver is configured to implement unbalance compensation control on each segment of the arc-shaped armature winding unit to suppress the vibration of the impeller.

2. The fan driven by a circumferentially distributed multi-segment circular arc motor as described in claim 1, characterized in that, At least one pair of bearings is provided between the central shaft and the impeller.

3. The fan driven by a circumferentially distributed multi-segment circular arc motor as described in claim 1, characterized in that, The central angle of each arc-shaped permanent magnet unit and the arc-shaped armature winding unit is less than 180°.

4. The fan driven by a circumferentially distributed multi-segment circular arc motor as described in claim 1, characterized in that, The number of the multi-segment arc-shaped permanent magnet units ranges from 1 to 8 segments, with gaps between each segment.

5. The fan driven by a circumferentially distributed multi-segment circular arc motor as described in claim 1, characterized in that, The motor driver is configured to provide phase-synchronized and independently current-controllable drive signals to each segment of the arc-shaped armature winding unit.

6. The fan driven by a circumferentially distributed multi-segment circular arc motor as described in claim 1, characterized in that, The outer surface of the external frame is provided with heat dissipation fins.

7. The fan driven by a circumferentially distributed multi-segment circular arc motor as described in claim 1, characterized in that, The power devices of the motor driver are thermally connected to the external frame.

8. The fan driven by a circumferentially distributed multi-segment circular arc motor as described in claim 1, characterized in that, The central flow channel area of ​​the impeller is not obstructed by any motor structure.

9. The fan driven by a circumferentially distributed multi-segment circular arc motor as described in claim 1, characterized in that, The multi-segment arc-shaped armature winding unit is wound using a concentrated winding method.

10. The fan driven by a circumferentially distributed multi-segment circular arc motor as described in claim 1, characterized in that, The output of a specific arc-shaped armature winding unit is compensated and adjusted based on the impeller vibration or position feedback to achieve vibration suppression or torque fluctuation smoothing.

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