Brushless motor suitable for double voltages and controller

Abstract

The utility model discloses a brushless motor suitable for double voltages and a controller, the motor comprises a rotor and a stator, the rotor is composed of a magnetic sheet and an iron core, and the magnetic field is kept unchanged; the magnetic field intensity and the distribution stability in the motor operation process are ensured, and efficient and stable operation of the motor is facilitated. According to the winding design of the stator, the series-parallel connection relation of the coils can be adjusted according to input signals under different voltages, so that the output rotating speeds are basically the same. The controller is used for being matched with the brushless motor; the controller judges the corresponding stator coil configuration by identifying the voltage of the input signal; and furthermore, the series-parallel connection relation of the coil is controlled to ensure that the output rotating speeds are basically the same under different voltage conditions.

Description

Technical Field

[0001] The present application relates to the field of motor control technology, and in particular to a brushless motor and controller suitable for dual voltage. Background Art

[0002] With the advancement of technology and changes in market demand, power tools are increasingly used in all walks of life. Among them, brushless DC motors have become the mainstream power source in power tools due to their high efficiency, low noise, and long life. However, in practical applications, especially in scenarios where portability and high power output are required, how to flexibly respond to power supply requirements of different voltage levels and ensure that the motor maintains similar output torque and speed at different voltages has become an important technical challenge.

[0003] In the current market, 18V or 20V battery packs are widely used, especially for light or medium-duty power tools. However, for some heavy equipment with higher power requirements, such as professional-grade electric drills and angle grinders, higher voltages (such as 36V or 40V) can more effectively provide the required power. In order to resolve this contradiction, and considering that users may want to use existing battery pack resources to avoid repeated investment, a brushless motor and its control circuit that is compatible with dual voltages (such as 18 / 20V and 36 / 40V) and maintains stable output performance came into being. Summary of the invention

[0004] The technical solution adopted by the present application to solve the technical problem is: a brushless motor applicable to dual voltage, the motor comprising a rotor and a stator, wherein:

[0005] The rotor is composed of magnetic sheets and an iron core, and the magnetic field remains unchanged;

[0006] The winding design of the stator can adjust the series and parallel relationship of the coils according to the input signals under different voltages to keep the output speed basically the same.

[0007] In one embodiment, the winding of the stator includes at least two coil groups, each coil group includes at least three coils, and the wire diameter and number of turns of each coil are the same;

[0008] Under dual voltage conditions, when a low voltage signal is received, the coils are connected in parallel so that the motor maintains the same output speed when operating at low voltage;

[0009] When a high voltage signal is received, the coils are connected in series so that the motor maintains the same output speed when operating at a high voltage.

[0010] In one embodiment, the input voltage signal is identified through the motor controller signal, and the corresponding stator coil configuration is determined according to the signal to ensure the output rotation speed is consistent.

[0011] In one embodiment, the coil connection method of the stator is applicable to multiple voltage levels with a multiple relationship.

[0012] In one embodiment, when the stator windings are two coil groups, the following wiring method is used:

[0013] When receiving a low voltage signal, the first coil group is connected in parallel with the second coil group, specifically: the lead-out terminal Ac' of the first coil group is connected with the lead-out terminal aC' of the second coil group, the lead-out terminal a'A of the first coil group is connected with the lead-out terminal Bb' of the coil group B, and the lead-out terminal B'C of the first coil group is connected with the lead-out terminal b'c of the second coil group, so that the motor works at a low voltage and keeps the output speed the same;

[0014] When a high voltage signal is received, the first coil group is connected in series with the second coil group, specifically: the lead-out terminal Ac' of the first coil group, the lead-out terminal Ba' of the second coil group and the lead-out terminal Cb' of the second coil group are sequentially connected in series, and at the same time, the lead-out terminal A' of the first coil group and the lead-out terminal a of the second coil group, the lead-out terminal B' of the first coil group and the lead-out terminal b of the second coil group, and the lead-out terminal C' of the first coil group and the lead-out terminal c of the second coil group are short-circuited respectively to form a series circuit, thereby ensuring that the output speed remains consistent when working under high voltage.

[0015] On the other hand, the present application provides a controller for matching the brushless motor described in any one of the above embodiments; the controller determines the corresponding stator coil configuration by identifying the voltage of the input signal; and then controls the series-parallel relationship of the coils to ensure that the output speed is basically the same under different voltage conditions.

[0016] The beneficial effects of the present application are: providing a brushless motor and its controller, which achieves consistent motor output speed under different voltage inputs by changing the series-parallel connection mode of the stator coil, effectively avoiding electromagnetic induction and damage to electronic components caused by voltage changes, while reducing material costs and improving the versatility and adaptability of the motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The present application is further described below in conjunction with the accompanying drawings and embodiments.

[0018] Figure 1 This is an example of the delta connection method of this application.

[0019] Figure 2 It is a first winding schematic diagram of the present application.

[0020] Figure 3 It is a schematic diagram of the second winding of this application.

[0021] Figure 4 This is the wiring diagram of the low voltage working state of this application.

[0022] Figure 5 This is a wiring diagram of the high voltage working state of this application. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in this field to achieve. When the combination of technical solutions is contradictory or cannot be achieved, it should be considered that the combination of such technical solutions does not exist and is not within the scope of protection of this application.

[0024] Please refer to Figure 1-5 As shown, it is a specific implementation of the present application: it is applicable to a dual-voltage brushless motor, the motor includes a rotor and a stator, wherein: the rotor is composed of a magnetic sheet and an iron core, and the magnetic field remains unchanged; to ensure the magnetic field strength and distribution stability during the operation of the motor, which is conducive to the efficient and stable operation of the motor. The winding design of the stator can adjust the series-parallel relationship of the coil according to the input signal under different voltages to keep the output speed basically the same.

[0025] In a specific example, the winding of the stator includes at least two coil groups, each coil group includes at least three coils, and the wire diameter and number of turns of each coil are the same; so as to ensure the consistency of electrical characteristics under different voltage modes.

[0026] Under dual voltage conditions, when a low voltage signal is received, the coils are connected in parallel so that the motor maintains the same output speed when working at a low voltage; when a high voltage signal is received, the coils are connected in series so that the motor maintains the same output speed when working at a high voltage.

[0027] In one embodiment, the input voltage signal is identified through the motor controller signal, and the corresponding stator coil configuration is determined according to the signal to ensure the output rotation speed is consistent.

[0028] In a specific example, when the stator winding has two coil groups, the following wiring method is used:

[0029] The basic working principle of brushless motor is that the rotor is a permanent magnet, and the magnetic flux remains unchanged. The output speed of the motor can be changed by changing the number of turns of the stator coil. Here, the wiring method of the six-slot stator is mostly triangle connection, such as Figure 1 The three coils lead out three wire ends AC', A'B, B'C. It is worth noting that the present application is not limited to a six-slot stator.

[0030] When the voltage is doubled, the motor is redesigned to meet the different voltages, that is, two sets of coils (refer to Figure 2 and Figure 3 ), namely the first winding and the second winding, each set of coils consists of three coils, and their wire diameters and number of turns are the same. The series-parallel relationship of the two coils is realized to correspond to different voltages.

[0031] When connected in parallel, the three lead wires have two sets of coils in parallel, and when connected in series, the three lead wires have Ac', Ba', and Cb', and the other wire ends A'a, B'b, and C'c are short-circuited. From the above observations, we can conclude that Ac', Ba', and Cb' exist in both series and parallel connections, so we only need to choose the connection method of the other six points to get different circuits, and the connection methods of related multiples can be realized by analogy;

[0032] Reference Figure 4 As shown, when a low voltage signal is received, select a and C' to connect and connect to Ac', and similarly connect A' and b to connect and connect to Ba', and similarly connect B' and c to connect and connect to Cb', so that the motor works at low voltage to ensure the same output speed

[0033] Reference Figure 5 As shown, when a high voltage signal is received, A'a, B'b, and C'c are short-circuited to form a parallel circuit to ensure the same output speed.

[0034] The above solution can solve the problem that when the two windings of the dual-voltage stator work at different voltages, one coil will always not work. The non-working coil will produce electromagnetic induction, which will cause damage to electronic components. It also saves material costs. The number of turns of the high-voltage winding must be a multiple of the low-voltage winding, which wastes materials. The total number of coils is 3N, and now only 2N coils are used in series and parallel.

[0035] The motor controller signal identifies whether the input power is 20V or 40V, and then determines the corresponding stator coil to ensure that the output speed remains consistent.

[0036] In addition, the stator coil connection method is applicable to multiple voltage levels with multiple relationships, which enhances the versatility and adaptability of the motor. Users can flexibly select power supplies of different voltage levels according to actual needs without worrying about the fluctuation of motor output performance. This design not only simplifies the use and maintenance of the equipment, but also reduces the user's equipment investment cost.

[0037] The present application also provides a controller matching the above brushless motor. The controller has the following functions:

[0038] Voltage identification: The controller can identify the voltage signal of the input power supply and accurately determine the current power supply voltage level.

[0039] Coil configuration determination: Based on the identified voltage signal, the controller can determine which series-parallel configuration the corresponding stator coil should adopt to ensure that the motor output speed is basically the same under different voltage conditions.

[0040] Coil control: The controller controls the series-parallel switching of the coil group in real time according to the judgment result, so as to realize the stable operation of the motor under dual voltage conditions.

[0041] So far, various embodiments of the present application have been described in detail. In order to avoid obscuring the concept of the present application, some details known in the art are not described. Based on the above description, those skilled in the art can fully understand how to implement the technical solution disclosed herein.

[0042] Finally, it should be noted that the above is only a preferred embodiment of the present application, and the aforementioned embodiments are only used to illustrate the technical solution of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, a person of ordinary skill in the art should understand that it is still possible to modify the technical solutions recorded in the aforementioned embodiments, or to make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not drive the essence of the corresponding technical solutions away from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. Suitable for dual voltage brushless motor, characterized in that, The motor comprises a rotor and a stator, wherein: The rotor is composed of magnetic sheets and an iron core, and the magnetic field remains unchanged; The winding design of the stator can adjust the series and parallel relationship of the coils according to the input signals under different voltages to keep the output speed basically the same.

2. The brushless motor suitable for dual voltage according to claim 1, characterized in that: The winding of the stator includes at least two coil groups, each coil group includes at least three coils, and the wire diameter and number of turns of each coil are the same; Under dual voltage conditions, when a low voltage signal is received, the coils are connected in parallel so that the motor maintains the same output speed when operating at low voltage; When a high voltage signal is received, the coils are connected in series so that the motor maintains the same output speed when operating at a high voltage.

3. The brushless motor suitable for dual voltage according to claim 1, characterized in that: The input voltage signal is identified through the motor controller signal, and the corresponding stator coil configuration is determined based on the signal to ensure consistent output speed.

4. The brushless motor suitable for dual voltage according to claim 1, characterized in that: The coil connection method of the stator is suitable for multiple voltage levels with multiple relationships.

5. The brushless motor suitable for dual voltage according to claim 1, characterized in that: When the stator is wound with two coil groups, the following wiring method is used: When receiving a low voltage signal, the first coil group is connected in parallel with the second coil group, specifically: the lead-out terminal Ac' of the first coil group is connected with the lead-out terminal aC' of the second coil group, the lead-out terminal a'A of the first coil group is connected with the lead-out terminal Bb' of the coil group B, and the lead-out terminal B'C of the first coil group is connected with the lead-out terminal b'c of the second coil group, so that the motor works at a low voltage and keeps the output speed the same; When a high voltage signal is received, the first coil group is connected in series with the second coil group, specifically: the lead-out terminal Ac' of the first coil group, the lead-out terminal Ba' of the second coil group and the lead-out terminal Cb' of the second coil group are sequentially connected in series, and at the same time, the lead-out terminal A' of the first coil group and the lead-out terminal a of the second coil group, the lead-out terminal B' of the first coil group and the lead-out terminal b of the second coil group, and the lead-out terminal C' of the first coil group and the lead-out terminal c of the second coil group are short-circuited respectively to form a series circuit, thereby ensuring that the output speed remains consistent when working under high voltage.

6. A controller, characterized in that: Used to match the brushless motor described in any one of claims 1 to 5; By identifying the voltage of the input signal, the corresponding stator coil configuration is determined; The series and parallel relationship of the coils is then controlled to ensure that the output speed is basically the same under different voltage conditions.

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