# Impact of Coil Misalignment in Data Transmission over the Inductive Link of an EV Wireless Charger

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## Abstract

**:**

## 1. Introduction

- (1).
- The coils are realistic for EV applications in terms of their dimensions and size.
- (2).
- Four types of compensation networks are considered, as Series–Series is not the only option considered in EV wireless chargers.
- (3).
- The reflected impedance is not neglected when deriving the electrical magnitudes affecting the computation of the channel capacity.
- (4).
- The vertical, horizontal and joint vertical and horizontal types of misalignments are analysed.

## 2. Overview of a Wireless EV Charger

## 3. Theoretical Analysis of the Coil Misalignment Effects on the Wireless Channel Capacity

## 4. Analysis of the Results

## 5. Conclusions

## Acknowledgments

## Author Contributions

## Conflicts of Interest

## References

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**Figure 1.**Structure of an Inductively Coupled Power Transfer (ICPT) wireless charger for electric vehicles (EV).

**Figure 3.**Illustration of the types of coil misalignments that may occur in an EV wireless charger: (

**a**) vertical misalignment; (

**b**) horizontal misalignment; (

**c**) vertical and horizontal misalignment.

**Figure 4.**Variations in the wireless channel capacity due to vertical misalignments. SS, Series–Series; SP, Series–Parallel; PP, Parallel–Parallel; PS, Parallel–Series; PSIM (Power Simulation Technology).

Topology | ${\mathit{C}}_{1}$ | ${\mathit{C}}_{2}$ |
---|---|---|

Series–Series | $\frac{1}{{\omega}^{2}{L}_{1}}$ | $\frac{1}{{\omega}^{2}{L}_{2}}$ |

Series–Parallel | $\frac{{L}_{2}^{2}{C}_{2}}{{L}_{1}{L}_{2}-{M}^{2}}$ | $\frac{1}{{\omega}^{2}{L}_{2}}$ |

Parallel–Series | $\frac{{L}_{2}{C}_{2}}{{L}_{1}+\frac{{M}^{4}}{{L}_{1}{L}_{2}{C}_{2}{R}_{b}^{2}}}$ | $\frac{1}{{\omega}^{2}{L}_{2}}$ |

Parallel–Parallel | $\frac{\left({L}_{1}{L}_{2}-{M}^{2}\right){L}_{2}^{2}{C}_{2}}{\frac{{M}^{4}{R}_{L}^{2}{C}_{2}}{{L}_{2}}+{\left({L}_{1}{L}_{2}-{M}^{2}\right)}^{2}}$ | $\frac{1}{{\omega}^{2}{L}_{2}}$ |

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

Output | 3.7 kW @ 300 V |

f [kHz] | 85 |

N_{1} [number of turns in the primary coil] | 11 |

N_{2} [number of turns in the secondary coil] | 14 |

a1 × b1 [m^{2}] | 0.75 × 0.75 |

a2 × b2 [m^{2}] | 0.5 × 0.5 |

gd [m] | 0.2 |

L_{1} [µH] | 240.5 |

L_{2} [µH] | 230.6 |

R_{1} [mΩ] | 196 |

R_{2} [mΩ] | 143 |

R_{b} [Ω] | 30 |

C_{2} [nF] | 15.20 |

C_{1} [nF] @ SS | 14.57 |

C_{1} [nF] @ SP | 15.02 |

C_{1} [nF] @ PS | 15.02 |

C_{1} [nF] @ PP | 14.36 |

M [µH] @ gap = 15 cm, xm = 0 cm | 49.78 |

M [µH] @ gap = 20 cm, xm = 0 cm | 40.8 |

M [µH] @ gap = 25 cm, xm = 0 cm | 33.38 |

M [µH] @ xm = 5 cm, gap = gd | 40.39 |

M [µH] @ xm = 10 cm, gap = gd | 39.07 |

M [µH] @ xm = 15 cm, gap = gd | 36.72 |

M [µH] @ xm = 5 cm, gap = 10 cm | 59.9 |

M [µH] @ xm = 10 cm, gap = 20 cm | 39.07 |

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**MDPI and ACS Style**

Triviño-Cabrera, A.; Lin, Z.; Aguado, J.A.
Impact of Coil Misalignment in Data Transmission over the Inductive Link of an EV Wireless Charger. *Energies* **2018**, *11*, 538.
https://doi.org/10.3390/en11030538

**AMA Style**

Triviño-Cabrera A, Lin Z, Aguado JA.
Impact of Coil Misalignment in Data Transmission over the Inductive Link of an EV Wireless Charger. *Energies*. 2018; 11(3):538.
https://doi.org/10.3390/en11030538

**Chicago/Turabian Style**

Triviño-Cabrera, Alicia, Zhengyu Lin, and José A. Aguado.
2018. "Impact of Coil Misalignment in Data Transmission over the Inductive Link of an EV Wireless Charger" *Energies* 11, no. 3: 538.
https://doi.org/10.3390/en11030538