# Non-Contact Measurement Method of Phase Current Based on Magnetic Field Decoupling Calculation for Three-Phase Four-Core Cable

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## Abstract

**:**

## 1. Introduction

## 2. Measurement Structure and Principle

#### 2.1. Determination of Measurement Model

#### 2.2. Principle of Magnetic Field Coupling Measurement and Determination of Decoupling Coefficient

## 3. Current Reconstruction Technology

#### 3.1. Determination of Deflection Angle

#### 3.2. Three-Phase Current Simulation and Reconstruction

#### 3.3. Evaluation of Reconstruction Current Accuracy

_{p}is the phase current obtained from the above analytical model, a and b are the cosine and sine coefficients, and f is the current frequency.

#### 3.4. Reduction of Cable Current with Different Section Sizes

^{2}cable is 20A and 100A, and its reduction current curve is shown in Figure 8. The input current of 25 mm

^{2}cable is 50A and 150A, and its reduction current curve is shown in Figure 9.

## 4. Design of Magnetic Array Current Sensor

#### 4.1. Measuring Principle of Fluxgate Sensor

#### 4.2. Design of Peripheral Parameters of Magnetic Array Sensor

#### 4.3. Matrix Relationship between Sensor Output Voltage and Three-Phase Current

## 5. Experimental Verification

#### 5.1. Establishment of Experimental Platform

#### 5.2. Analysis and Discussion of Experimental Results

#### 5.3. Linear Error and Sensitivity of Sensor

## 6. Conclusions

## Author Contributions

## Funding

## Acknowledgments

## Conflicts of Interest

## Appendix A

## References

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**Figure 5.**Distribution diagram of magnetic induction intensity under asymmetric current when the deflection angle is 30° at t = 0.0581.

**Figure 8.**Schematic diagram of 16 mm

^{2}reduction current. (

**a**) Reduction current at 20 A; (

**b**) Reduction current at 100 A.

**Figure 9.**Schematic diagram of 25 mm

^{2}reduction current. (

**a**) Reduction current at 50 A; (

**b**) Reduction current at 150 A.

**Figure 17.**Different current reduction waveforms. (

**a**) Restore waveform when current is 4 A; (

**b**) restore waveform when current is 5 A.

**Figure 18.**Different current reduction waveforms. (

**a**) Restore waveform when current is 3 A; (

**b**) restore waveform when current is 2 A.

$\mathbf{Angle}\left(\mathit{\theta}\right)$ | Array1 (P2/P1) | Array2 (P3/P1) | Array3 (P4/P1) |
---|---|---|---|

0 | 0.734912 | 0.993191 | 0.363180 |

1 | 0.739019 | 0.997070 | 0.364397 |

2 | 0.737446 | 1.001517 | 0.366266 |

… | … | … | … |

357 | 0.734047 | 0.992519 | 0.367433 |

358 | 0.731474 | 0.991843 | 0.364359 |

359 | 0.732534 | 0.993064 | 0.363779 |

Phase Sequence | a | b | $\sqrt{{\mathit{a}}^{2}+{\mathit{b}}^{2}}$ | $\mathit{\phi}/\xb0$ |
---|---|---|---|---|

A | 7.09 | 0.02 | 7.10 | 0.5 |

B | −2.81 | −4.90 | 5.64 | −121.8 |

C | −2.11 | 3.67 | 4.23 | 122.5 |

N | 2.13 | −1.22 | 2.45 | −28.8 |

Phase Sequence | Valid Value | Amplitude Error (%) | Phase Angle Error (°) |
---|---|---|---|

A | 5.0619 | 1.44 | −1.8 |

B | 4.0825 | 2.06 | 1.98 |

C | 3.0845 | 2.81 | 2.78 |

N | 2.3867 | 2.56 | 1.3 |

Phase Sequence/Current | 1 A | 2 A | 3 A | 4 A |
---|---|---|---|---|

Error (%) | ||||

A | 1.8 | 1.6 | 1.53 | 1.38 |

B | 1.8 | 1.8 | 1.74 | 1.42 |

C | 2.1 | 2.1 | 1.69 | 1.48 |

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**MDPI and ACS Style**

Suo, C.; Cheng, K.; Wang, L.; Zhang, W.; Liu, X.; Zhu, J.
Non-Contact Measurement Method of Phase Current Based on Magnetic Field Decoupling Calculation for Three-Phase Four-Core Cable. *Electronics* **2023**, *12*, 1443.
https://doi.org/10.3390/electronics12061443

**AMA Style**

Suo C, Cheng K, Wang L, Zhang W, Liu X, Zhu J.
Non-Contact Measurement Method of Phase Current Based on Magnetic Field Decoupling Calculation for Three-Phase Four-Core Cable. *Electronics*. 2023; 12(6):1443.
https://doi.org/10.3390/electronics12061443

**Chicago/Turabian Style**

Suo, Chunguang, Kang Cheng, Lifeng Wang, Wenbin Zhang, Xi Liu, and Junyu Zhu.
2023. "Non-Contact Measurement Method of Phase Current Based on Magnetic Field Decoupling Calculation for Three-Phase Four-Core Cable" *Electronics* 12, no. 6: 1443.
https://doi.org/10.3390/electronics12061443