A dual-output axial magnetic field modulation magnetic gear using a C-type magnetic modulation ring

Abstract

The present invention belongs to the technical field of axial magnetic field modulation magnetic gears and discloses a dual-output axial magnetic field modulation magnetic gear utilizing a C-type magnetic modulation ring. The gear comprises a high-speed permanent magnet rotor, a low-speed permanent magnet rotor, and a C-type modulation ring. The high-speed permanent magnet rotor is positioned between the two low-speed permanent magnet rotors, and the C-type modulation ring is nested and installed between the high-speed permanent magnet rotor and the low-speed permanent magnet rotor, leaving four layers of air gap between the three. The present invention divides the high-speed permanent magnet rotor into two equal parts, upper and lower, and adds a non-magnetic composite material in the gap. This ensures that the magnetic field generated by the high-speed permanent magnet rotor is evenly distributed to the upper and lower low-speed rotors, achieving balanced dual-end output. The present invention utilizes a C-type modulation ring to reduce magnetic flux leakage at the outer end of the high-speed rotor and increase the air gap flux density between the high-speed rotor and the C-type magnetic modulation ring, thereby reducing torque pulsation and increasing output torque density. Furthermore, the C-type modulation ring enables dual-end output, improving transmission efficiency and expanding the application range of magnetic gears.

Description

Technical Field

[0001] The invention belongs to the technical field of axial magnetic field modulation type magnetic gears, and relates to a dual-output axial magnetic field modulation type magnetic gear using a C-type magnetic modulation ring. Background Art

[0002] Early exploration of magnetic gears began in the early 20th century. Their operating principle mimics that of mechanical gears, widely used to match the speed of a prime mover to its load requirements. While high torque density can be achieved, lubrication is often required, and mechanical gears can present issues with noise, vibration, and reliability in certain environments.

[0003] Magnetic gears use the interaction between magnetic poles to transmit power. However, due to the low magnetic energy product and high demagnetization risk of ferrite permanent magnets, they have low torque density, poor practicality, and slow development. It was not until the 1980s that the emergence of high-performance rare earth permanent magnet materials such as neodymium iron boron significantly improved the magnetic field strength and stability, laying the foundation for subsequent practical applications. After that, structural innovation became a key research direction. In 2001, K. Atallah and D. Howe proposed a concentric magnetic gear design using rare earth permanent magnets in the paper "A novel high-performance magnetic gear" in IEEE Transactions on Magnetics. The magnetic ring was used to optimize the harmonic distribution of the air gap magnetic field, greatly improving the torque density and permanent magnet utilization. Simulation studies have shown that the torque density it transmits exceeds 100 kNm / m. 3 This paper became the technical benchmark for the development of magnetic gears. Subsequently, scholars proposed various topological structures such as axial disc and Halbach array.

[0004] Current technical challenges for magnetic gears focus on torque fluctuations, permanent magnet magnetic flux leakage, and eddy current losses. These challenges necessitate the development of novel topologies and optimized magnetic circuits to enhance stability. Magnetic gear applications have expanded into new energy and specialized operating environments. The integration of magnetic gears with motors is widely used in wind power generation and electric vehicle hub motors. Applications requiring high temperatures, high pressures, and sealed environments, such as chemical pumps and aerospace, are leveraging the advantages of contactless transmission from magnetic gears, gradually replacing traditional mechanical transmission systems. Summary of the Invention

[0005] In order to overcome the shortcomings of magnetic gears that usually have a single output and magnetic flux leakage on the outer surface of the high-speed rotor permanent magnet, and to improve system working efficiency, reduce torque pulsation, and increase output torque density with dual output, the present invention provides a dual-output axial magnetic field modulation magnetic gear using a C-type magnetic modulation ring.

[0006] The technical solution of the present invention:

[0007] A dual-output axial magnetic field modulation magnetic gear using a C-type magnetic modulation ring includes a high-speed permanent magnet rotor, two low-speed permanent magnet rotors and a C-type modulation ring; the high-speed permanent magnet rotor is located between the two low-speed permanent magnet rotors, and the C-type modulation ring is nested and installed between the high-speed permanent magnet rotor and the low-speed permanent magnet rotor, with four layers of air gaps left between the three; the air gap between the high-speed permanent magnet rotor and the C-type modulation ring and the air gap between the low-speed permanent magnet rotor and the C-type modulation ring are both 1 mm.

[0008] The high-speed permanent magnet rotor includes a high-speed rotor N-pole permanent magnet, a high-speed rotor S-pole permanent magnet and a high-speed rotor yoke. The high-speed rotor N-pole permanent magnet and the high-speed rotor S-pole permanent magnet are arranged alternately, and the high-speed rotor yoke is located between the high-speed rotor N-pole permanent magnet and the high-speed rotor S-pole permanent magnet. Among them, the high-speed rotor N-pole permanent magnet includes n N-pole NdFeB permanent magnets; the high-speed rotor S-pole permanent magnet includes n S-pole NdFeB permanent magnets; the high-speed rotor yoke includes 2n rotor yokes; and a 1mm air gap is left in the middle of the height of the N-pole NdFeB permanent magnet, the S-pole NdFeB permanent magnet and the rotor yoke. A non-magnetic composite material is added to the air gap to divide the high-speed permanent magnet rotor into two parts.

[0009] The low-speed permanent magnet rotor includes a low-speed rotor N-pole permanent magnet, a low-speed rotor S-pole permanent magnet and a low-speed rotor yoke. The low-speed rotor N-pole permanent magnet and the low-speed rotor S-pole permanent magnet are arranged alternately, and the low-speed rotor yoke is located between the low-speed rotor N-pole permanent magnet and the low-speed rotor S-pole permanent magnet; wherein, the low-speed rotor N-pole permanent magnet includes n N-pole neodymium iron boron permanent magnets, the low-speed rotor S-pole permanent magnet includes n S-pole neodymium iron boron permanent magnets, and the low-speed rotor yoke includes 2n rotor yokes.

[0010] The C-type modulation ring includes an equal number of silicon steel magnetic modulation pole pieces and non-magnetic composite material pole pieces that are alternately arranged.

[0011] Furthermore, the C-shaped modulation ring includes 19 silicon steel magnetic modulation pole pieces and 19 non-magnetic composite material pole pieces that are alternately arranged.

[0012] Furthermore, the C-shaped modulation ring surrounds the top and outer end of the high-speed rotor yoke, so that the leakage magnetic flux from the outer end of the high-speed rotor yoke is coupled with the magnetic circuit of the low-speed rotor yoke through the C-shaped modulation ring, thereby reducing the leakage magnetic flux at the outer end of the permanent magnet and increasing the air gap magnetic density, thereby achieving the purpose of reducing torque pulsation and improving output torque and torque density.

[0013] The magnetic circuit of the upper half of the magnetic gear starts from the high-speed N-pole NdFeB permanent magnet, passes through the high-speed rotor yoke, high-speed air gap, C-type modulation ring, low-speed air gap, low-speed rotor yoke, and reaches the low-speed S-pole NdFeB permanent magnet. The magnetic circuit of the lower half is the same as the upper magnetic circuit. The number of permanent magnet pole pairs of the high-speed permanent magnet rotor is P h, the number of permanent magnet pole pairs of the low-speed permanent magnet rotor is P l , the number of magnetic pole pieces of the C-type modulation ring is N s To maximize torque transmission, the pole pair relationship between the rotor and stator is P h +P l =N s , the permanent magnet is magnetized along the entire circumferential direction.

[0014] The high-speed permanent magnet rotor is divided into two equal parts, with a non-magnetic composite material added in the gap. This prevents the non-uniform transfer of the magnetic field generated by the high-speed rotor's permanent magnets to the upper and lower low-speed rotors. The addition of the non-magnetic composite material evenly distributes the magnetic field generated by the high-speed permanent magnet rotor between the upper and lower low-speed rotors, balancing the output torque at both ends.

[0015] The dual-output axial magnetic field modulation type magnetic gear has 19 C-shaped modulation ring magnetic pole pieces, which are evenly distributed on the circumference. The other parts are filled with non-magnetic materials as fixing parts, which reduces the overall mass of the magnetic gear, reduces eddy current losses to a certain extent, and improves the torque density per unit mass.

[0016] Beneficial effects of the present invention:

[0017] (1) The high-speed rotor is artificially divided into two equal parts from the middle, and non-magnetic composite materials are added in the gap to force the magnetic field excited by the high-speed rotor to be evenly distributed to the upper and lower low-speed rotors, balancing the double-end output.

[0018] (2) The use of a C-type modulation ring first reduces the magnetic flux leakage at the outer end of the high-speed rotor and increases the air gap magnetic density between the high-speed rotor and the C-type modulation ring, thereby reducing torque pulsation and increasing output torque density. Secondly, the C-type modulation ring structure can achieve double-end output, improving transmission efficiency and expanding the application range of magnetic gears. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 1 is an exploded view of an axial magnetic field modulation type magnetic gear using a C-shaped modulation ring in an embodiment of the present invention.

[0020] Figure 2 Schematic diagram of the structure of the N-pole permanent magnet of the low-speed rotor in an embodiment of the present invention.

[0021] Figure 3 It is a schematic diagram of the low-speed rotor yoke structure in an embodiment of the present invention.

[0022] Figure 4 Schematic diagram of the S-pole permanent magnet structure of the low-speed rotor in an embodiment of the present invention.

[0023] Figure 5Schematic diagram of the C-type modulation ring structure in an embodiment of the present invention.

[0024] Figure 6 Schematic diagram of the structure of the N-pole permanent magnet of the high-speed rotor in an embodiment of the present invention.

[0025] Figure 7 It is a schematic diagram of the high-speed rotor yoke structure in an embodiment of the present invention.

[0026] Figure 8 Schematic diagram of the S-pole permanent magnet structure of the high-speed rotor in an embodiment of the present invention.

[0027] Figure 9 It is a schematic diagram of the structure of the C-type modulation ring and the high-speed rotor in an embodiment of the present invention.

[0028] Figure 10 This is a torque simulation diagram of a single high-speed rotor and two low-speed rotors in an embodiment of the present invention.

[0029] In the figure: 1 low-speed rotor N-pole permanent magnet; 2 low-speed rotor yoke; 3 low-speed rotor S-pole permanent magnet; 4 C-type modulation ring; 5 high-speed rotor N-pole permanent magnet; 6 high-speed rotor yoke; 7 high-speed rotor S-pole permanent magnet. DETAILED DESCRIPTION

[0030] The specific implementation of the present invention is further described below in conjunction with the accompanying drawings and technical solutions.

[0031] Combine Figure 1 An axial magnetic field modulation magnetic gear using a C-shaped modulation ring structure comprises a high-speed permanent magnet rotor, a stator C-shaped modulation ring, and two low-speed permanent magnet rotors. The high-speed permanent magnet rotor is located between the two low-speed permanent magnet rotors, and the C-shaped modulation ring is nested between the high-speed and low-speed permanent magnet rotors, with four air gaps between them. The air gaps between the high-speed permanent magnet rotor and the C-shaped modulation ring, as well as the air gaps between the low-speed permanent magnet rotor and the C-shaped modulation ring, are both 1 mm.

[0032] Combine Figures 2 to 4 The low-speed permanent magnet rotor includes 15 low-speed rotor N-pole permanent magnets 1, 15 low-speed rotor S-pole permanent magnets 3 and 30 low-speed rotor yokes 2. The low-speed rotor N-pole permanent magnets 1 and the low-speed rotor S-pole permanent magnets 3 are arranged alternately, and the low-speed rotor yoke 2 is located between the low-speed rotor N-pole permanent magnet and 1 low-speed rotor S-pole permanent magnet 3; wherein, the low-speed rotor N-pole permanent magnet 1 includes n N-pole neodymium iron boron permanent magnets, the low-speed rotor S-pole permanent magnet 3 includes n S-pole neodymium iron boron permanent magnets, and the low-speed rotor yoke includes 2n rotor yokes.

[0033] Combine Figure 5 The C-shaped modulation ring 4 includes an equal number of silicon steel magnetic modulation pole pieces and non-magnetic composite material pole pieces that are alternately arranged.

[0034] Furthermore, the C-shaped modulation ring includes 19 silicon steel magnetic modulation pole pieces and 19 non-magnetic composite material pole pieces that are alternately arranged.

[0035] Furthermore, the C-shaped modulation ring surrounds the top and outer end of the high-speed rotor yoke, so that the leakage magnetic flux from the outer end of the high-speed rotor yoke is coupled with the magnetic circuit of the low-speed rotor yoke through the C-shaped modulation ring, thereby reducing the leakage magnetic flux at the outer end of the permanent magnet and increasing the air gap magnetic density, thereby achieving the purpose of reducing torque pulsation and improving output torque and torque density.

[0036] Combine Figures 6 to 8 The high-speed permanent magnet rotor includes 4 high-speed rotor N-pole permanent magnets 5, 4 high-speed rotor S-pole permanent magnets 7 and 8 high-speed rotor yokes 6. The high-speed rotor N-pole permanent magnets 5 and the high-speed rotor S-pole permanent magnets 7 are arranged alternately, and the high-speed rotor yoke 6 is located between the high-speed rotor N-pole permanent magnets 5 and the high-speed rotor S-pole permanent magnets 7; wherein, the high-speed rotor N-pole permanent magnet 5 includes n N-pole NdFeB permanent magnets; the high-speed rotor S-pole permanent magnet 7 includes n S-pole NdFeB permanent magnets; the high-speed rotor yoke 6 includes 2n rotor yokes; and a 1 mm air gap is left in the middle of the height of the N-pole NdFeB permanent magnet, the S-pole NdFeB permanent magnet and the rotor yoke, and a non-magnetic composite material is added to the air gap to divide the high-speed permanent magnet rotor into two parts.

[0037] Combine Figure 9 , non-magnetic composite materials are added to the 1mm air gap left in the center of the high-speed rotor to divide it into two even parts, upper and lower.

[0038] The magnetic circuit of the upper half of the magnetic gear starts from the high-speed N-pole NdFeB permanent magnet, passes through the high-speed rotor yoke, high-speed air gap, C-type modulation ring, low-speed air gap, low-speed rotor yoke, and reaches the low-speed S-pole NdFeB permanent magnet. The magnetic circuit of the lower half is the same as the upper magnetic circuit. The number of permanent magnet pole pairs of the high-speed permanent magnet rotor is P h , the number of permanent magnet pole pairs of the low-speed permanent magnet rotor is P l , the number of magnetic pole pieces of the C-type modulation ring is N s To maximize torque transmission, the pole pair relationship between the rotor and stator is P h +P l =N s , the permanent magnet is magnetized along the entire circumferential direction.

[0039] The high-speed permanent magnet rotor is divided into two equal parts, with a non-magnetic composite material added in the gap. This prevents the non-uniform transfer of the magnetic field generated by the high-speed rotor's permanent magnets to the upper and lower low-speed rotors. The addition of the non-magnetic composite material evenly distributes the magnetic field generated by the high-speed permanent magnet rotor between the upper and lower low-speed rotors, balancing the output torque at both ends.

[0040] The dual-output axial magnetic field modulation type magnetic gear has 19 C-shaped modulation ring magnetic pole pieces, which are evenly distributed on the circumference. The other parts are filled with non-magnetic materials as fixing parts, which reduces the overall mass of the magnetic gear, reduces eddy current losses to a certain extent, and improves the torque density per unit mass.

Claims

1. A dual-output axial magnetic field modulation magnetic gear using a C-type magnetic modulation ring, characterized in that: The dual-output axial magnetic field modulation magnetic gear using a C-type magnetic modulation ring includes a high-speed permanent magnet rotor, two low-speed permanent magnet rotors, and a C-type modulation ring. The high-speed permanent magnet rotor is located between the two low-speed permanent magnet rotors, and the C-type modulation ring is nested between the high-speed permanent magnet rotor and the low-speed permanent magnet rotor, with four air gaps between the three. The high-speed permanent magnet rotor includes a high-speed rotor N-pole permanent magnet, a high-speed rotor S-pole permanent magnet and a high-speed rotor yoke. The high-speed rotor N-pole permanent magnet and the high-speed rotor S-pole permanent magnet are alternately arranged, and the high-speed rotor yoke is located between the high-speed rotor N-pole permanent magnet and the high-speed rotor S-pole permanent magnet. The high-speed rotor N-pole permanent magnet includes n N-pole neodymium iron boron permanent magnets; the high-speed rotor S-pole permanent magnet includes n S-pole neodymium iron boron permanent magnets; and the high-speed rotor yoke includes 2n rotor yokes. A 1mm air gap is left between the N-pole NdFeB permanent magnet, the S-pole NdFeB permanent magnet and the rotor yoke. Non-magnetic composite material is added to the air gap to divide the high-speed permanent magnet rotor into two parts. The low-speed permanent magnet rotor includes a low-speed rotor N-pole permanent magnet, a low-speed rotor S-pole permanent magnet and a low-speed rotor yoke. The low-speed rotor N-pole permanent magnet and the low-speed rotor S-pole permanent magnet are arranged alternately, and the low-speed rotor yoke is located between the low-speed rotor N-pole permanent magnet and the low-speed rotor S-pole permanent magnet; wherein, the low-speed rotor N-pole permanent magnet includes n N-pole neodymium iron boron permanent magnets, the low-speed rotor S-pole permanent magnet includes n S-pole neodymium iron boron permanent magnets, and the low-speed rotor yoke includes 2n rotor yokes.

2. The dual-output axial magnetic field modulation magnetic gear using a C-shaped magnetic modulation ring according to claim 1, characterized in that: The air gap between the high-speed permanent magnet rotor and the C-shaped modulation ring and the air gap between the low-speed permanent magnet rotor and the C-shaped modulation ring are both 1 mm.

3. The dual-output axial magnetic field modulation magnetic gear using a C-shaped magnetic modulation ring according to claim 1, characterized in that: The C-shaped modulation ring includes an equal number of silicon steel magnetic modulation pole pieces and non-magnetic composite material pole pieces that are alternately arranged.

4. The dual-output axial magnetic field modulation magnetic gear using a C-shaped magnetic modulation ring according to claim 1, characterized in that: The C-shaped modulation ring surrounds the top and outer end of the high-speed rotor yoke.

Images