Research on the excitation method of symmetrical spiral online detecting sensor of metal debris

Abstract

By connecting the symmetrical spiral inductive sensor to the oil return pipeline of the lubricating oil, a full flow online detection of the size, quantity and other parameters of the tiny metal debris particles in the lubricating oil solution is realised. Inductive sensors are used to excite symmetrical double helix coils, and alternating electromagnetic fields are generated. Changes in induced electromotive force are detected by the centre induction coil. In order to improve the detection accuracy of tiny metal debris particles, the degree of anti-jamming of the excitation signal, and the transmission distance, a method of stimulating using sinusoidal AC steady current signals was designed. The sinusoidal signal generator is designed based on FPGA, and the sinusoidal AC steady current excitation signal is realised through differential amplification, low-pass filtering, and AC steady current amplification, and experimental verification is performed to achieve better excitation and detection results.

Keywords

• electric potential
• inductive sensors
• inductance
• electromagnetic fields
• field programmable gate arrays
• coils
• low-pass filters
• signal generators
• electric sensing devices
• lubricating oils
• electromagnetic induction
• tiny metal debris particles
• stimulating using sinusoidal ac steady current signals
• sinusoidal signal generator
• sinusoidal ac steady current excitation signal
• ac steady current amplification
• excitation method
• symmetrical spiral inductive sensor
• oil return pipeline
• other parameters
• lubricating oil solution
• inductive sensors
• symmetrical double helix coils
• induced electromotive force
• centre induction coil
• detection accuracy