# Performance Investigation and Cogging Torque Reduction in a Novel Modular Stator PM Flux Reversal Machine

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## Abstract

**:**

## 1. Introduction

## 2. Operation Principle

#### 2.1. Rotor Poles and Stator Slots

#### 2.2. Winding Layout

## 3. Design Methodology

## 4. Rotor Pole Study and Flux Distribution

- Here
- ${J}_{a}$ = current density,
- ${N}_{a}$ = number of turns,
- ${\alpha}_{a}$ = filling factor,
- ${S}_{a}$ = slots area,
- ${I}_{a}$ = input current,

## 5. Results and Discussion

#### 5.1. Coil Arrangement Test

#### 5.2. U-Phase Flux Linkage

#### 5.3. Cogging Torque

#### 5.4. Back-EMF

#### 5.5. Instantaneous Torque

#### 5.6. Average Torque vs. Current Density

#### 5.7. Selection of Design for Cogging Torque Reduction

#### 5.7.1. Notching

#### 5.7.2. Arc of the Rotor Pole

#### 5.7.3. Flange of the Rotor Pole

#### 5.7.4. Hybrid Notch and Flange

#### 5.7.5. Hybrid Notch and Arc

#### 5.7.6. Hybrid Arc and Flange

#### 5.7.7. Hybrid Arc, Flange, and Notch

#### 5.8. Effect of Cogging Torque Reduction Techniques on No-Load Flux

#### 5.9. Effect of Cogging Torque Reduction Techniques on No-Load Back-EMF

#### 5.10. Effect of Cogging Torque Reduction Techniques on Harmonics

#### 5.11. Effect of Cogging Torque Reduction Techniques on Torque Ripple

#### 5.12. Effect of Cogging Torque Reduction Techniques on Average Torque vs. Current Density

## 6. Conclusions

## Author Contributions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Conflicts of Interest

## Abbreviations

PM | Permanent magnet |

EMF | Electromotive force |

SRM | Switched reluctance machine |

FRPMM | Flux reversal permanent magnet machines |

FSCW | Fractional slot concentrated winding |

FEFRM | Field excited flux reversal machine |

HPMFRM | Hybrid permanent magnet flux reversal machine |

MSFRPMM | Modular stator flux reversal permanent magnet machine |

MS | Modular stator |

FEA | Finite element analysis |

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**Figure 1.**Coil-phase arrangement of the proposed model. (

**a**) Phase-coil connections. (

**b**) Phase-coil connection vectors.

**Figure 3.**Various rotor poles of a modular stator PM flux reversal machine. (

**a**) 8-P/12-S. (

**b**) 10-P/12-S. (

**c**) 11-P/12-S. (

**d**) 13-P/12-S. (

**e**) 14-P/12-S.

**Figure 4.**Flux distribution at various electrical degrees. (

**a**) 0${}^{\circ}$. (

**b**) 90${}^{\circ}$. (

**c**) 180${}^{\circ}$. (

**d**) 270${}^{\circ}$.

Parameters | Value |
---|---|

Number of phases | 3 |

Armature current density ${J}_{a}$ | 30 |

Number of stator slots | 12 |

Rotor pole | 8, 10, 11, 13, 14 |

Outer radius of stator (mm) | 62 |

Stack length (mm) | 60 |

Air gap b/w stator rotor (mm) | 0.3 |

Armature slot area (mm^{2}) | 157.16 |

No. of turns per armature coil slot | 80 |

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**MDPI and ACS Style**

Khan, S.; Pasund, A.; Ahmad, N.; Ahmed, S.; Khan, H.A.; Cheema, K.M.; Milyani, A.H.
Performance Investigation and Cogging Torque Reduction in a Novel Modular Stator PM Flux Reversal Machine. *Energies* **2022**, *15*, 2261.
https://doi.org/10.3390/en15062261

**AMA Style**

Khan S, Pasund A, Ahmad N, Ahmed S, Khan HA, Cheema KM, Milyani AH.
Performance Investigation and Cogging Torque Reduction in a Novel Modular Stator PM Flux Reversal Machine. *Energies*. 2022; 15(6):2261.
https://doi.org/10.3390/en15062261

**Chicago/Turabian Style**

Khan, Surat, Abdin Pasund, Naseer Ahmad, Shoaib Ahmed, Hamid Ali Khan, Khalid Mehmood Cheema, and Ahmad H. Milyani.
2022. "Performance Investigation and Cogging Torque Reduction in a Novel Modular Stator PM Flux Reversal Machine" *Energies* 15, no. 6: 2261.
https://doi.org/10.3390/en15062261