Motor position detection system and pan-tilt unit using rotor magnetic ring

Abstract

This invention discloses a motor position detection system and a pan-tilt unit utilizing a rotor magnetic ring. The system includes: a motor rotor with a rotor magnetic ring having multiple magnetic poles; a first magnetic induction element; and a second magnetic induction element. The spatial arrangement of the first magnetic induction element relative to the second magnetic induction element is configured such that, when the rotor magnetic ring rotates, the second sine wave signal output by the second magnetic induction element forms a 90-degree phase difference with the first sine wave signal output by the first magnetic induction element. This invention, by constructing the relative spatial position between the first and second magnetic induction elements to output two sine wave signals with a 90-degree phase difference when the rotor magnetic ring rotates, utilizes the inherent rotor magnetic ring of the motor to replace the dedicated single-pole magnetic ring in traditional solutions. This significantly reduces material costs and simplifies the motor structure while ensuring high-precision angle detection.

Description

Technical Field

[0001] This utility model relates to the field of motor position detection technology, and in particular to a motor position detection system and gimbal using a rotor magnetic ring. Background Technology

[0002] Existing gimbal motors and other devices requiring high-precision angle positioning typically rely on an additional angle sensor system for rotation angle detection. This traditional approach usually includes two linear Hall effect sensors and a single-pole magnetic ring dedicated to angle detection.

[0003] However, this existing technical solution has the following inherent drawbacks: First, it requires an additional, high-precision single-pole magnetic ring, which not only increases material costs but also increases the complexity of motor assembly and overall size. Second, this solution has extremely high requirements for the magnetic declination accuracy of this dedicated magnetic ring; any manufacturing or installation error of the magnetic ring will directly lead to a decrease in angle detection accuracy. Utility Model Content

[0004] The main purpose of this invention is to provide a motor position detection system using a rotor magnetic ring. The main objective is to improve the system structure, eliminate the need for a dedicated single-pole magnetic ring, and achieve high-precision angle detection using the inherent rotor magnetic ring of the motor, thereby reducing costs and simplifying the structure.

[0005] To achieve the above objectives, the present invention proposes a motor position detection system using a rotor magnetic ring, comprising: An electric motor rotor having a rotor magnetic ring having multiple magnetic poles; First magnetic induction element; Second magnetic induction element; The spatial placement of the first magnetic induction element relative to the second magnetic induction element is configured such that when the rotor magnetic ring rotates, the second sine wave signal output by the second magnetic induction element forms a 90-degree phase difference with the first sine wave signal output by the first magnetic induction element.

[0006] Optionally, the motor position detection system using a rotor magnetic ring further includes: The processing unit is connected to the signal output terminals of the first magnetic induction element and the second magnetic induction element respectively, and is used to sample the first sine wave signal and the second sine wave signal; The processing unit is also used to calculate the motor rotation angle value based on the first sine wave signal and the second sine wave signal.

[0007] Optionally, the first and second magnetic sensing elements include Hall sensors.

[0008] Optionally, the spatial angle difference between the first magnetic induction element and the second magnetic induction element is one-quarter of an odd multiple of the mechanical angle of the magnetic field period.

[0009] Optionally, the spatial arrangement angle between the first magnetic induction element and the second magnetic induction element satisfies the following formula: , in, The spatial placement angle of the second magnetic induction element. Let P be the spatial placement angle of the first magnetic induction element, P be the number of magnetic poles of the rotor magnetic ring, and K be a natural number.

[0010] Optionally, when the spatial placement angle of the first magnetic induction element is 0° and the number of magnetic poles of the rotor magnetic ring is 8, the spatial placement angle of the second magnetic induction element is ±22.5°, 112.5°, 67.5°, 202.5°, 157.5°, 247.5°, 292.5° or 337.5°.

[0011] Optionally, when the spatial placement angle of the first magnetic induction element is 0° and the number of magnetic poles of the rotor magnetic ring is 10, the spatial placement angle of the second magnetic induction element is ±18°, 54°, 90°, 126°, 162°, 198°, 234°, 270°, 306° or 342°.

[0012] Optionally, when the spatial placement angle of the first magnetic induction element is 0° and the number of magnetic poles of the rotor magnetic ring is 14, the spatial placement angle of the second magnetic induction element is ±12.9°, 38.6°, 64.3°, 90°, 115.7°, 141.4°, 167.1°, 192.9°, 218.6°, 244.3°, 270°, 295.7°, 321.4°, or 347.1°.

[0013] Optionally, the first magnetic sensing element and the second magnetic sensing element are disposed on the same PCB board.

[0014] This utility model also proposes a gimbal, including: a motor and the motor position detection system using a rotor magnetic ring.

[0015] This invention discloses a motor position detection system and a pan-tilt unit utilizing a rotor magnetic ring. The motor position detection system includes: a motor rotor having a rotor magnetic ring with multiple magnetic poles; a first magnetic induction element; and a second magnetic induction element. The spatial arrangement of the first magnetic induction element relative to the second magnetic induction element is configured such that when the rotor magnetic ring rotates, the second sine wave signal output by the second magnetic induction element forms a 90-degree phase difference with the first sine wave signal output by the first magnetic induction element. This invention, by constructing the relative spatial position between the first and second magnetic induction elements to output two sine wave signals with a 90-degree phase difference when the rotor magnetic ring rotates, utilizes the inherent rotor magnetic ring of the motor to replace the dedicated single-pole magnetic ring in traditional solutions. This significantly reduces material costs and simplifies the motor structure while ensuring high-precision angle detection. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the first and second magnetic induction elements and the position of the rotor magnetic ring, as an example of a motor position detection system using a rotor magnetic ring according to this utility model. Figure 2 This is a spatial arrangement diagram showing the 90-degree phase difference between the output waveforms of the first Hall sensor and the second Hall sensor in an embodiment of the motor position detection system using a rotor magnetic ring according to this utility model. Figure 3 This is a list of common spatial placement angles of motors in the second embodiment of the motor position detection system using a rotor magnetic ring according to this utility model; Figure 4 This is a schematic diagram of the motor structure of an embodiment of the gimbal of this utility model.

[0018] The realization of the purpose, functional features and advantages of this utility model will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0019] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0020] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in this utility model embodiment are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.

[0021] In this utility model, unless otherwise explicitly specified and limited, the terms "connection," "fixing," etc., should be interpreted broadly. For example, "fixing" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0022] Furthermore, in this utility model, descriptions involving "first," "second," etc., are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this utility model.

[0023] This utility model proposes a motor position detection system using a rotor magnetic ring, comprising: An electric motor rotor having a rotor magnetic ring having multiple magnetic poles; First magnetic induction element; Second magnetic induction element; The spatial placement of the first magnetic induction element relative to the second magnetic induction element is configured such that when the rotor magnetic ring rotates, the second sine wave signal output by the second magnetic induction element forms a 90-degree phase difference with the first sine wave signal output by the first magnetic induction element.

[0024] It should be explained that the magnetic field of the multi-pole rotor magnetic ring used in motor drive is sinusoidally distributed in space. By carefully setting the relative spatial position of the two magnetic induction elements, their output signals can be made to have a 90-degree phase difference. In this way, the system does not require a dedicated single-pole magnetic ring; the angle can be calculated directly using the existing rotor magnetic ring through subsequent processing. The core concept of this utility model is to abandon the dedicated single-pole magnetic ring and instead use the multi-pole rotor magnetic ring inherent in the motor body used to drive the motor as the magnetic signal source for angle detection. By carefully designing the relative spatial position of the two magnetic induction elements, they can output two sinusoidal wave signals with a 90-degree phase difference.

[0025] When the magnetic ring rotates, the magnetic induction element outputs two sinusoidal signals with a 90-degree phase difference. The angle can be obtained by calculating the arctangent of the two sinusoidal signals.

[0026] A rotor magnetic ring is fixedly mounted on the motor rotor. This rotor magnetic ring has P magnetic poles (P is an even number greater than 2), such as 8 poles, 10 poles, 14 poles, etc. This rotor magnetic ring is an inherent component for the motor to achieve commutation and torque output. A first magnetic induction element is fixedly disposed around the rotor magnetic ring. A second magnetic induction element is fixedly disposed around the rotor magnetic ring. The key improvement of this utility model lies in the relative spatial relationship between the first magnetic induction element and the second magnetic induction element.

[0027] Specifically, the spatial arrangement of the second magnetic induction element relative to the first magnetic induction element is configured such that when the rotor magnetic ring rotates, the second sine wave signal output by the second magnetic induction element forms a 90-degree phase difference with the first sine wave signal output by the first magnetic induction element.

[0028] Traditional methods use a single-pole magnetic ring, which generates a sinusoidal wave in one rotation, aiming to produce an ideal, pure sinusoidal magnetic field in space. As it rotates, fixed points around it experience a magnetic field whose intensity changes periodically according to a sinusoidal law. One rotation (360° mechanical angle) corresponds to one complete cycle of the magnetic field change (360° electrical angle), with two linear Hall sensors fixed around it at a 90-degree mechanical angle.

[0029] This invention discovers that the magnetic field of a multi-pole rotor magnetic ring used in motor drives is itself a near-sinusoidal periodic distribution in space. Each rotation of the rotor results in a fixed point in space experiencing P / 2 complete magnetic field cycles. Therefore, this rotor magnetic ring fully possesses the physical conditions to serve as an angle detection signal source. Although the motor rotor magnetic ring (multi-pole) has a large number of pole pairs (e.g., 4 pairs for 8 poles), the magnetic field generated by each pair of magnetic poles (NS poles) in its surrounding space, under ideal conditions, is also a sinusoidal periodic field. Each rotation of the rotor results in a fixed point in space experiencing multiple pairs of magnetic poles, thus sensing multiple (P / 2, where P is the number of magnetic poles) complete sinusoidal magnetic field cycles. The two are essentially identical in their physical essence of "generating a spatial sinusoidal periodic magnetic field." The motor rotor magnetic ring can be viewed as a compact spatial combination of multiple "single-pole magnetic rings." This provides the most fundamental physical premise for substitution.

[0030] A single-pole magnetic ring outputs one sine wave per revolution; while an 8-pole (4 pairs of poles) rotor magnetic ring outputs four sine waves per revolution. That is, their "electrical cycle" and "mechanical cycle" have different ratios.

[0031] The breakthrough of this invention lies in recognizing that to output two orthogonal signals using a rotor magnetic ring, it is not necessary to change the magnetic ring itself, but rather to achieve this by optimizing the relative positions of two stationary sensors. Traditional solutions rigidly assume that to obtain a signal with a 90-degree phase difference, the two Hall sensors must be placed at a 90-degree mechanical angle. This rule only applies to single-pole magnetic rings with a "one-rotation-one-cycle" pattern. This invention breaks this conventional thinking. What we truly need is not a fixed 90-degree mechanical angle, but rather a 90-degree phase difference between the two signals. For multi-pole rotor magnetic rings, as long as the mechanical angle between the two Hall sensors is an odd multiple of 1 / 4 of a "magnetic field spatial cycle," a 90-degree phase difference in the output signal can be guaranteed, thus completing motor position identification. For example, for an 8-pole motor, the magnetic field spatial cycle is 360° / 4 = 90°. A quarter period is 90° / 4 = 22.5°. Therefore, by placing the two sensors at a mechanical angle of 22.5° (or 67.5°, 112.5°, etc.), a sine wave with a 90-degree phase difference can be output.

[0032] This invention, by redefining the structural feature of the relative positional relationship between two sensors, successfully adapts multiple sinusoidal wave cycles output by a multi-pole rotor magnetic ring to a signal processing system originally designed for a single-pole magnetic ring. The key lies in transforming the fixed mindset of a "90-degree mechanical angle" into a dynamic design rule of a "1 / 4 magnetic field cycle mechanical angle." In signal processing, to unambiguously calculate angles using the arctangent function, two reference signals with a 90-degree phase difference (i.e., orthogonal) are required. This invention, through structural design, positions the two sensors spatially at an odd multiple of 1 / 4 of a magnetic field cycle, thereby forcibly introducing this crucial 90-degree phase difference between their output signals.

[0033] This specific relative position is something that those skilled in the art would not have considered in traditional solutions, because the conventional thinking is to use an independent single-pole magnetic ring with a magnetic field period of 360°, and the corresponding 1 / 4 period is a 90-degree mechanical angle. However, this utility model creatively adapts this requirement of "90-degree phase difference" to a driving magnetic ring with a completely different period, and achieves it through a brand-new structural angle related to the number of magnetic poles.

[0034] Since the rotor magnetic ring is the core component of the motor, its manufacturing and installation precision is typically very high. Using it for angle detection avoids errors introduced by additional magnetic ring installation deviations (such as misalignment or magnetic declination), thus improving the potential accuracy of the angle detection system from the source. Furthermore, it directly eliminates the need for a high-precision single-pole magnetic ring, utilizing only the motor's inherent rotor magnetic ring for angle detection, significantly reducing material costs. Additionally, it's important to emphasize that this solution is a universal design method; once the number of poles of the rotor magnetic ring is determined, the placement of the two magnetic induction elements can be calculated, making it widely applicable to brushless motors with various pole numbers. Figure 1 As shown, Figure 1 This is a schematic diagram showing the positions of the first magnetic induction element, the second magnetic induction element, and the rotor magnetic ring in one example.

[0035] This invention discloses a motor position detection system using a rotor magnetic ring, comprising: a motor rotor having a rotor magnetic ring with multiple magnetic poles; a first magnetic induction element; and a second magnetic induction element. The spatial arrangement of the first magnetic induction element relative to the second magnetic induction element is configured such that, when the rotor magnetic ring rotates, the second sine wave signal output by the second magnetic induction element forms a 90-degree phase difference with the first sine wave signal output by the first magnetic induction element. This invention, by constructing the relative spatial position between the first and second magnetic induction elements to output two sine wave signals with a 90-degree phase difference when the rotor magnetic ring rotates, utilizes the inherent rotor magnetic ring of the motor to replace the dedicated single-pole magnetic ring in traditional solutions. This significantly reduces material costs and simplifies the motor structure while ensuring high-precision angle detection.

[0036] In one example, the first and second magnetic sensing elements include Hall sensors.

[0037] In the first embodiment, the spatial angle difference between the first magnetic induction element and the second magnetic induction element is one-quarter of an odd multiple of the mechanical angle of the magnetic field period.

[0038] It needs to be explained that for a rotor magnetic ring with P poles, its magnetic field is not randomly distributed in space, but exhibits a strong periodicity. The angle spanned by a complete magnetic field cycle (i.e., one N pole and one S pole) in mechanical space is the mechanical angle of the magnetic field cycle, calculated using the following formula: For example, for an 8-pole motor, the corresponding mechanical angle is 90°, which means that inside the motor, the magnetic field distribution repeats every 90° of mechanical angle; for a 10-pole motor, the corresponding mechanical angle is 72°. This parameter is the core bridge linking the motor's electrical characteristics with its mechanical structure design.

[0039] We need the electrical signals output by the two magnetic sensing elements to have a 90-degree phase difference in time. Because the rotor rotates continuously, the spatial differences in the magnetic field distribution are converted into a temporal signal phase difference. If the two sensors are spatially separated by 1 / 4 of a magnetic field cycle, then when the same magnetic pole (e.g., the N pole) rotates past both sensors sequentially, the change in the magnetic field sensed by the second sensor will be delayed by 1 / 4 of a cycle compared to the first sensor. A complete cycle is 360°, and this 1 / 4-cycle delay is exactly the 90-degree phase lag.

[0040] Furthermore, since the magnetic field is periodic, taking an 8-pole motor as an example, the relative magnetic field relationship is exactly the same whether the position is offset by 1 / 4 of the cycle (i.e., 22.5°) in the first cycle or by 1 / 4 of the cycle (i.e., 90° + 22.5° = 112.5°) in the second cycle. This is because 112.5° = 90° (one complete cycle) + 22.5°. The extra entire cycle does not affect the relative phase relationship.

[0041] Only a quarter of a cycle of the offset magnetic field period mechanical angle (i.e., Only when the formula expression (which may differ, but is not limited here) is the orthogonality condition of the two signals always guaranteed, can this be ensured. Take an 8-pole motor as an example: 1 / 4 cycle: Angle difference = 22.5° -> Output Sin and Cos signals.

[0042] 2 / 4 period: Angle difference = 45°. At this point, the two sensors are at the peak and trough of the sine wave, respectively, outputting signals with a phase difference of 180 degrees, i.e., -Sin. This cannot be used for arctan calculations.

[0043] 3 / 4 period: Angular difference = 67.5°. Spatially, 67.5° = 90° - 22.5°. This means that sensor 2, relative to sensor 1, can be considered to be offset in the opposite direction by 1 / 4 period. Signal-wise, this will cause it to output a -Cos signal. The phase difference between Sin and -Cos, after a simple mathematical transformation, remains 90 degrees.

[0044] 4 / 4 (i.e., 1) cycle: angle difference = 90°. The two sensors are at the exact same magnetic field phase point, outputting in-phase signals with a phase difference of 0 degrees.

[0045] 5 / 4 cycle: Angle difference = 112.5° = 90° + 22.5°. This is equivalent to 1 / 4 cycle, where the output recovers to Sin and Cos.

[0046] Only when offset by 1 / 4, 3 / 4, 5 / 4... periods can the two signals be guaranteed to always satisfy the condition of orthogonality (a phase difference of 90° or 270°, where 270° is equivalent to -90°, and computationally equivalent). This invention uses odd multiples to summarize the effective positions of this infinite sequence.

[0047] It should be noted that the whole concept of "odd multiples of a quarter" defines an infinite, discrete set of "effective locations".

[0048] The odd multiple determines the membership of this set. It precisely selects all the positions that can guarantee that the output signal always satisfies the orthogonality (phase difference of 90 degrees or its equivalent) from all possible fraction points, while excluding all invalid positions (such as out-of-phase points and in-phase points).

[0049] One-quarter determines the basic step relationship and physical meaning between each point in this set (achieving a 90-degree phase difference). For example... Figure 2 As shown, the spatial arrangement of the first Hall sensor and the second Hall sensor output waveforms with a 90-degree phase difference is illustrated.

[0050] In the first example of this embodiment, the spatial arrangement angle between the first magnetic sensing element and the second magnetic sensing element satisfies the following formula: , in, The spatial placement angle of the second magnetic induction element. Let P be the spatial placement angle of the first magnetic induction element, P be the number of magnetic poles of the rotor magnetic ring, and K be a natural number.

[0051] It is easy to understand that, Including 1 / 4, 3 / 4, 5 / 4, 7 / 4, and 9 / 4, it can ensure that the two signals always meet the orthogonality condition.

[0052] In the second example of this embodiment, the spatial arrangement angle between the first magnetic induction element and the second magnetic induction element satisfies the following formula: , in, The spatial placement angle of the second magnetic induction element. Let P be the spatial placement angle of the first magnetic induction element, P be the number of magnetic poles of the rotor magnetic ring, and K be a natural number.

[0053] In the second embodiment, the motor position detection system using a rotor magnetic ring further includes: The processing unit is connected to the signal output terminals of the first magnetic induction element and the second magnetic induction element respectively, and is used to sample the first sine wave signal and the second sine wave signal; The processing unit is also used to calculate the motor rotation angle value based on the first sine wave signal and the second sine wave signal.

[0054] It should be explained that the first sine wave signal and the second sine wave signal form a 90-degree phase difference, and the motor angle can be calculated using the arctangent function.

[0055] The first and second magnetic sensing elements (such as linear Hall sensors) output two continuous, weak analog voltage signals. The analog-to-digital converter (ADC) module inside the processing unit (which can be an MCU, SOC, or DSP, etc.) synchronously samples these two signals at fixed time intervals and converts the acquired analog voltage values ​​into discrete digital quantities.

[0056] After obtaining the digital values ​​of the two signals sampled at the same time, the processing unit executes the embedded software algorithm to perform calculations, such as implementing the formula calculations described above.

[0057] This invention achieves its technical effect through the spatial placement of the first and second magnetic induction elements (corresponding to the difference in their spatial placement angles). For ease of calculation, the spatial placement angle of one element can be defined as 0°, and the spatial placement angle of the other element can be calculated.

[0058] The following provides calculations for the spatial placement angles of commonly used 8-pole, 10-pole, and 14-pole motors. Figure 3 As shown, in one example, when the spatial placement angle of the first magnetic induction element is 0° and the number of magnetic poles of the rotor magnetic ring is 8, the spatial placement angle of the second magnetic induction element is ±22.5°, 112.5°, 67.5°, 202.5°, 157.5°, 247.5°, 292.5° or 337.5°.

[0059] In another example, when the spatial placement angle of the first magnetic induction element is 0° and the number of magnetic poles of the rotor magnetic ring is 14, the spatial placement angle of the second magnetic induction element is ±12.9°, 38.6°, 64.3°, 90°, 115.7°, 141.4°, 167.1°, 192.9°, 218.6°, 244.3°, 270°, 295.7°, 321.4°, or 347.1°.

[0060] In another example, when the spatial placement angle of the first magnetic induction element is 0° and the number of magnetic poles of the rotor magnetic ring is 10, the spatial placement angle of the second magnetic induction element is ±18°, 54°, 90°, 126°, 162°, 198°, 234°, 270°, 306° or 342°.

[0061] In the third embodiment of this utility model, the first magnetic induction element and the second magnetic induction element are disposed on the same PCB board.

[0062] This embodiment addresses the issues of accuracy maintenance and reliability that sensors may encounter during manufacturing and long-term use through a specific and optimized physical structure.

[0063] The core innovation of this invention lies in the precise and specific relative spatial position between the two magnetic sensing elements. The stability of this relative position is the key to ensuring the accuracy of angle detection.

[0064] Mounting two magnetic sensing elements together on the same PCB board to form a sensor module ensures that their relative position remains unchanged throughout manufacturing and the product's lifespan. Precision PCB manufacturing processes ensure that the distance and angle between the sensor centers soldered to the two pads are highly consistent with the design values. The rigid fixation of the PCB board permanently locks the relative position of the two sensors after leaving the factory, preventing changes due to transportation vibrations, temperature variations, or long-term use. This fundamentally guarantees that every product using this solution can stably reproduce the orthogonal signal quality calculated during design, thus ensuring consistent angle detection accuracy during mass production.

[0065] Furthermore, in traditional designs, mounting two sensors as independent components onto the motor housing requires two separate positioning, alignment, and fixing processes. This is not only inefficient but also introduces independent errors with each installation, potentially accumulating beyond acceptable limits. With this solution, the two magnetic sensing elements are integrated into a single module. During motor assembly, the entire PCB board can be treated as a single component, allowing for a one-time positioning and installation. This significantly simplifies the assembly process.

[0066] This utility model also proposes a gimbal, including: a motor and the motor position detection system using a rotor magnetic ring.

[0067] It's easy to understand that the core function of a gimbal (especially a camera gimbal and a drone stabilization gimbal) is to achieve high-precision, high-smoothness, and high-response speed rotation and positioning of a load (such as a camera) in one or more axes of space. Its performance is based on the ability to acquire the true angular position of the motor shaft in real time and accurately, thereby forming a closed-loop position control system.

[0068] To achieve the aforementioned high-precision angle detection, traditional gimbal motors have to adopt the "dual Hall sensor + dedicated single-pole magnetic ring" solution described in the background section. This results in high gimbal motor costs, increased axial length, and complex assembly processes, ultimately limiting the cost-effectiveness and market competitiveness of gimbal products.

[0069] By applying the rotor magnetic ring-based motor position detection system of this invention to the gimbal, the expensive dedicated magnetic ring and related precision mounting structure can be eliminated, directly reducing the material cost (BOMCost) and manufacturing cost of the gimbal motor from the core component level, thus enabling the widespread adoption of high-performance gimbals. Reducing the number of components and axial space occupation allows for the design of more compact and lighter gimbal motors. A lighter gimbal means lower motor load and longer battery life (especially important for drone gimbals), improving the overall performance of the end product.

[0070] This utility model does not limit the application scenarios and products of the described gimbal. For example... Figure 4 As shown, Figure 4 This is a schematic diagram of the motor.

[0071] Since the gimbal includes the motor position detection system using a rotor magnetic ring, the specific structure of which is described in the above embodiments is as described in the present invention. Since this subject matter adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, and will not be described in detail here.

[0072] The above description is only an optional embodiment of the present utility model and does not limit the patent scope of the present utility model. All equivalent structural transformations made under the concept of the present utility model and using the contents of the present utility model specification and drawings, or direct / indirect applications in other related technical fields, are included in the patent protection scope of the present utility model.

Claims

1. A motor position detection system using a rotor magnetic ring, characterized in that, include: An electric motor rotor having a rotor magnetic ring having multiple magnetic poles; First magnetic induction element; Second magnetic induction element; The spatial placement of the first magnetic induction element relative to the second magnetic induction element is configured such that when the rotor magnetic ring rotates, the second sine wave signal output by the second magnetic induction element forms a 90-degree phase difference with the first sine wave signal output by the first magnetic induction element.

2. The motor position detection system using a rotor magnetic ring as described in claim 1, characterized in that, The motor position detection system using a rotor magnetic ring also includes: The processing unit is connected to the signal output terminals of the first magnetic induction element and the second magnetic induction element respectively, and is used to sample the first sine wave signal and the second sine wave signal; The processing unit is also used to calculate the motor rotation angle value based on the first sine wave signal and the second sine wave signal.

3. The motor position detection system using a rotor magnetic ring as described in claim 2, characterized in that, The first and second magnetic sensing elements include Hall sensors.

4. The motor position detection system using a rotor magnetic ring as described in any one of claims 1 to 3, characterized in that, The spatial angle difference between the first and second magnetic induction elements is one-quarter of an odd multiple of the mechanical angle of the magnetic field period.

5. The motor position detection system using a rotor magnetic ring as described in claim 4, characterized in that, The spatial arrangement angle between the first magnetic induction element and the second magnetic induction element satisfies the following formula: ， in, The spatial placement angle of the second magnetic induction element. Let P be the spatial placement angle of the first magnetic induction element, P be the number of magnetic poles of the rotor magnetic ring, and K be a natural number.

6. The motor position detection system using a rotor magnetic ring as described in claim 4 or claim 5, characterized in that, When the spatial placement angle of the first magnetic induction element is 0° and the number of magnetic poles of the rotor magnetic ring is 8, the spatial placement angle of the second magnetic induction element is ±22.5°, 112.5°, 67.5°, 202.5°, 157.5°, 247.5°, 292.5° or 337.5°.

7. The motor position detection system using a rotor magnetic ring as described in claim 4 or claim 5, characterized in that, When the spatial placement angle of the first magnetic induction element is 0° and the number of magnetic poles of the rotor magnetic ring is 10, the spatial placement angle of the second magnetic induction element is ±18°, 54°, 90°, 126°, 162°, 198°, 234°, 270°, 306° or 342°.

8. The motor position detection system using a rotor magnetic ring as described in claim 4 or claim 5, characterized in that, When the spatial placement angle of the first magnetic induction element is 0° and the number of magnetic poles of the rotor magnetic ring is 14, the spatial placement angle of the second magnetic induction element is ±12.9°, 38.6°, 64.3°, 90°, 115.7°, 141.4°, 167.1°, 192.9°, 218.6°, 244.3°, 270°, 295.7°, 321.4°, or 347.1°.

9. The motor position detection system using a rotor magnetic ring as described in any one of claims 1 to 3, characterized in that, The first magnetic sensing element and the second magnetic sensing element are disposed on the same PCB board.

10. A gimbal, characterized in that, include: The electric motor and the motor position detection system using a rotor magnetic ring as described in any one of claims 1 to 9.

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