Highly Enhanced Inductance Sensing Performance of Dual-Quartz Crystal Converter

Area of Science:

• Electrical Engineering
• Metrology
• Materials Science

Background:

• Accurate low inductance measurement is crucial for applications like non-destructive testing and magnetic material analysis.
• Traditional quartz crystal converters face limitations due to parasitic effects and temperature sensitivity, hindering precise low inductance detection.

Purpose of the Study:

• To significantly improve the inductance sensitivity of a quartz crystal converter for low inductance measurements.
• To develop a converter capable of compensating for temperature variations and parasitic influences.

Main Methods:

• Utilizing two parallel-connected quartz crystals with added capacitance in the oscillator circuit.
• Implementing a switchable oscillator and multiplexer switches for compensation of temperature-frequency characteristics and parasitic elements.
• Investigating the influence of hysteresis and parallel capacitances on converter sensitivity.

Main Results:

• Achieved improved sensitivity and effective compensation for dynamic temperature influences on output frequency.
• Demonstrated simultaneous compensation of fundamental quartz crystal frequency-temperature characteristics within 0-40 °C.
• Reported a frequency instability of ±0.05 ppm over 0-40 °C for inductance measurements between 85-100 μH, yielding a resolution of 1 pH.

Conclusions:

• The developed quartz crystal converter offers enhanced sensitivity and stability for low inductance measurements.
• The compensation techniques effectively mitigate temperature and parasitic influences, enabling high-resolution inductance detection.
• The converter is suitable for applications requiring precise low inductance measurement, non-destructive testing, and impedance analysis.