Development of a Transient Magnetic Field Sensor Based on Digital Integration and Frequency Equalization.

Area of Science:

• Electromagnetics and Sensor Technology
• Signal Processing

Background:

• Transient magnetic field sensors are crucial for electromagnetic environment measurements.
• Existing sensors may face limitations in accuracy and bandwidth for dynamic field analysis.

Purpose of the Study:

• To develop a novel magnetic field sensor with enhanced precision and a wide bandwidth.
• To improve the accuracy of magnetic field signal integration and compensate for system bandwidth loss.

Main Methods:

• Designed a novel sensor using a B-DOT loop antenna and a digital integrator.
• Implemented an improved Al-Alaoui algorithm for digital integration to minimize errors.
• Developed a Finite Impulse Response (FIR) filter for frequency compensation in the optical fiber system.
• Designed a low-noise transimpedance amplifier for the receiver circuit.

Main Results:

• Achieved a sensitivity of 68.2 A·m⁻¹/mV.
• Demonstrated a dynamic range of 50 dB (1-300 kA/m) and a linear correlation coefficient of 0.96.
• Obtained a bandwidth exceeding 100 MHz with flat amplitude-frequency characteristics.
• Verified performance under A-type lightning current conditions.

Conclusions:

• The developed digital integrator magnetic field sensor exhibits high-precision performance.
• Its wide bandwidth and dynamic range make it suitable for demanding applications.
• Potential applications include lightning positioning, partial discharge testing, and electromagnetic compatibility management.