Table 1.
Accuracy requirements of calibration
| Requirements | Numerical value |
|---|---|
| Calibration range (T) | 2–5 |
| Calibration step (Gs) | 300 |
| Accuracy | <(0.001% × reading + 0.005% × range) |
| Resolution (Gs) | 0.2–0.4 |
Fig. 1.
SENIS Low-Noise Teslameter 3MH5 and Hall probe C.
Fig. 2.
Metrolab PT2025 NMR Teslameter (a) and probe model 1062 (b).
Fig. 3.
Simulation model of the magnetic calibration pole.
Fig. 4.
Calibration pole design analysis.
Fig. 5.
Schematic diagram of magnetic field distribution of calibration poles.
Fig. 6.
Decomposition diagram of calibration tooling model.
Fig. 7.
Installation diagram of calibration tool in cyclotron.
Fig. 8.
Experimental platform and calibration system.
Fig. 9.
Temperature test bench.
Fig. 10.
Relationship between the energizing current and the probe temperature.
Fig. 11.
Relationship between the excitation current I and the required calibration magnetic induction intensity B.
Fig. 12.
Flow chart of Hall probe calibration process.
Fig. 13.
Drawing curves of magnetic induction intensity and temperature values.
Fig. 14.
Calibration point value reading and calibration table creation.
Fig. 15.
Calibration data fitting in program.
Fig. 16.
Fitting curves of polynomial Bpol1.
Table 2.
Fitting results of polynomial Bpol1
| Temperature, T | Polynomial fitting Bpol1 formula |
|---|---|
| T1 = 20°C | Bpol1 = −0.0080 − 1.1681*U − 0.0013*U2 − 3.4368e-4*U3 |
| T2 = 26°C | Bpol1 = −0.0044 − 1.1681*U − 6.080e-4*U2 − 3.7612e-4*U3 |
| T3 = 32°C | Bpol1 = −7.3829e-4 − 1.1672*U + 1.066e-4*U2 − 4.0922e-4*U3 |
Fig. 17.
Scatter diagram of ΔB2.
Fig. 18.
Calibration relative error curves.