# Novel Axial Flux-Switching Permanent Magnet Machine for High-Speed Applications

^{*}

## Abstract

**:**

## 1. Introduction

## 2. Design Evaluation of Proposed 6/4 FSPM Machines

#### 2.1. Fundamental Configuration

#### 2.2. Operation Principle

#### 2.3. Even Harmonic Cancellation

## 3. Analytical Calculation of Proposed 6/4 FSPM Machine

#### 3.1. Magnetic Circuit Analysis

^{th}harmonic amplitude of the back-EMF.

#### 3.2. Parameter Optimization

## 4. Performance Evaluation

#### 4.1. Open-Circuit Magnetic Field Distribution

#### 4.2. Open-Circuit Flux Linkage and Back-EMF

#### 4.3. Cogging Torque

#### 4.4. Output Power and Efficiency

#### 4.5. Output Torque

## 5. Discussion

## 6. Conclusions

## Author Contributions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Conflicts of Interest

## References

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**Figure 1.**6/4 AxFSPM structure diagram: (

**a**) exploded view; (

**b**) vertical view; (

**c**) stator core module.

**Figure 2.**Alternating magnetic flux path variation of the 6/4 FSPM within half an electric cycle: (

**a**) electrical angle of initial position is 0; (

**b**) 1/6 electric cycle; (

**c**) 1/3 electric cycle; (

**d**) 1/2 electric cycle.

**Figure 4.**Resultant magnet flux linkage waveform for total coils of phase A windings (A1 + A2 + A3 + A4).

**Figure 5.**FFT of the resultant magnet flux linkage waveform for total coils of phase A windings (A1 + A2 + A3 + A4).

**Figure 9.**Magnetic circuit model of the 6/4 FSPM machine under a pair of magnetic poles at 1/6 electric angle.

**Figure 12.**The dimension parameters of the 6/4 FSPM machine: (

**a**) cross-sectional view; (

**b**) vertical view of rotor.

**Figure 16.**6/4 AxFSPM machine magnetic field density distribution at open-circuit: (

**a**) Axis aligned of the outer PM and rotor pole. (

**b**) Axis aligned of the outer stator teeth and rotor pole.

**Figure 17.**6/4 AxFSPM machine flux linkage waveforms and FFT results: (

**a**) Flux linkage waveforms. (

**b**) FFT results of flux linkage.

**Figure 18.**6/4 AxFSPM machine back-EMF waveforms and FFT results: (

**a**) Back-EMF waveforms. (

**b**) FFT result of back-EMF.

Radial FSPM Machine | Axial FSPM Machine | Proposed Model | ||
---|---|---|---|---|

Slot/pole | 12/10 [12] | 6/4 [14] | 6/4 [17] | 6/4 |

Axial length | Long | Long | Short | Shortest |

Fundamental frequency | High | Low | Low | Low |

Efficiency | low | High | High | High |

Dissipate heat | Good | Bad | Better | Better |

Parameter | Symbol | Lower | Upper | Units |
---|---|---|---|---|

Stator yoke height | ${L}_{\mathrm{s}\_\mathrm{e}}$ | 15 | 35 | mm |

Stator tooth height | ${h}_{\mathrm{s}\_\mathrm{t}}$ | 10 | 20 | mm |

Inner stator tooth internal diameter | ${r}_{ii}$ | 90 | 120 | mm |

Inner stator tooth width | ${w}_{\mathrm{is}}$ | 30 | 50 | mm |

Radial magnetized PMs inner diameter | ${r}_{\mathrm{PM}}$ | 200 | 240 | mm |

Radial magnetized PMs thickness | ${w}_{\mathrm{PM}\_\mathrm{r}}$ | 3 | 6 | mm |

Outer stator tooth internal diameter | ${r}_{\mathrm{oi}}$ | 240 | 260 | mm |

Rotor yoke height | ${L}_{\mathrm{r}\_\mathrm{e}}$ | 10 | 30 | mm |

Rotor tooth angle | ${\theta}_{\mathrm{r}\_\mathrm{t}}$ | 15 | 45 | deg |

Parameter | Value | Parameter | Value |
---|---|---|---|

Turns of outer winding | 50 | Angle between inner and outer rotor teeth/deg | 45 |

Turns of inner winding | 68 | Rated speed (rpm) | 3000 |

Stator yoke height ${L}_{\mathrm{s}\_\mathrm{e}}$ (mm) | 28 | Outer stator tooth internal diameter ${r}_{\mathrm{oi}}$ (mm) | 252 |

Stator tooth height ${h}_{\mathrm{s}\_\mathrm{t}}$ (mm) | 20 | Outer stator tooth width ${w}_{\mathrm{os}}$ (mm) | 25 |

Inner stator tooth internal diameter ${r}_{ii}$ (mm) | 114 | Tangential magnetized PMs width ${w}_{\mathrm{PM}\_\mathrm{t}}$ (mm) | 6 |

Inner stator tooth width ${w}_{\mathrm{is}}$ (mm) | 43.6 | Rotor yoke height ${L}_{\mathrm{r}\_\mathrm{e}}$ (mm) | 17 |

Radial magnetized PMs inner diameter ${r}_{\mathrm{PM}}$ (mm) | 220 | Rotor tooth height ${h}_{\mathrm{r}\_\mathrm{t}}$ (mm) | 20 |

Radial magnetized PMs thickness ${w}_{\mathrm{PM}\_\mathrm{r}}$ (mm) | 6 | Rotor tooth angle ${\theta}_{\mathrm{r}\_\mathrm{t}}$ (mm) | 17 |

Radial magnetized PMs angle ${\theta}_{\mathrm{PM}\_\mathrm{r}}$ (deg) | 55 | Air gap height ${\mathrm{g}}_{\mathsf{\delta}}$ (mm) | 1 |

Radial FSPM Machine | Axial FSPM Machine | Proposed Model | ||
---|---|---|---|---|

Slot/pole | 12/10 [12] | 6/4 [14] | 6/4 [17] | 6/4 |

Number of stators | 1 | 2 | 1 | 2 |

Number of rotors | 1 | 1 | 2 | 1 |

Axial length/outer diameter (mm) | 0.58 | 0.83 | 0.57 | 0.33 |

Fundamental frequency (Hz) | 500 | 200 | 200 | 200 |

Iron loss (W) | 524 | 412 | 425 | 423 |

Efficiency (%) | 86 | 91 | 92 | 90 |

Cogging torque (Nm) | 0.3 | 2.3 | 21.5 | 4.5 |

THD of back-EMF (%) | 0.2 | 5.8 | 8.9 | 9.8 |

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## Share and Cite

**MDPI and ACS Style**

Zhang, H.; Xu, Z.; Liu, C.; Jin, L.; Yu, H.; Xu, B.; Fang, S.
Novel Axial Flux-Switching Permanent Magnet Machine for High-Speed Applications. *Sustainability* **2022**, *14*, 7774.
https://doi.org/10.3390/su14137774

**AMA Style**

Zhang H, Xu Z, Liu C, Jin L, Yu H, Xu B, Fang S.
Novel Axial Flux-Switching Permanent Magnet Machine for High-Speed Applications. *Sustainability*. 2022; 14(13):7774.
https://doi.org/10.3390/su14137774

**Chicago/Turabian Style**

Zhang, Hongbin, Zhike Xu, Chenglei Liu, Long Jin, Haitao Yu, Bingxin Xu, and Shuhua Fang.
2022. "Novel Axial Flux-Switching Permanent Magnet Machine for High-Speed Applications" *Sustainability* 14, no. 13: 7774.
https://doi.org/10.3390/su14137774