If wear particles generated during the operation of automobile engines are not
monitored in time, they will contaminate the lubricating oil, leading to system
failures or even accidents. Therefore, real-time wear particle monitoring is
crucial for the stable operation of engines. Among mainstream wear particle
monitoring sensors, the three-coil inductive sensor demonstrates significant
application potential due to its ability to distinguish wear particle materials
and strong resistance to environmental interference. However, its insufficient
sensitivity to small-diameter wear particles limits further performance
improvement. This paper takes the three-coil inductive wear particle monitoring
sensor as the research object. First, a mathematical model of the sensor’s
operation is established based on the law of electromagnetic induction,
clarifying the relationship between structural parameters (such as channel
radius, turns, coil spacing, and length) and the peak induced voltage.
Subsequently, Multiphysics simulation software is employed to quantitatively
analyze the influence of each structural parameter on the induced voltage,
identifying directions for parameter optimization. Furthermore, orthogonal
experiments are conducted to optimize discrete parameters, determining optimal
levels for key parameters such as channel radius and coil spacing. Then, the
simulated annealing algorithm is applied to achieve precise optimization of
continuous parameters, ultimately obtaining the optimal combination of coil
structural parameters. Experimental validation based on the optimized parameters
shows that the peak-to-peak induced voltage for 1000 μm wear particles measured
by the sensor optimized with the simulated annealing algorithm reaches 2.43 V,
which is approximately 41 times higher than the 0.06 V observed before
optimization. Additionally, the optimization effect of the simulated annealing
algorithm further improves by 38.86% compared to the orthogonal experiment. In
addition, experimental tests were also carried out on small-diameter abrasive
particles of 100 μm, with the peak-to-peak value of the induced voltage reaching
0.38 V. The results confirm that this coil structural parameter optimization
method effectively enhances the sensor’s sensitivity to small-diameter wear
particles, providing a theoretical basis and technical support for the
structural design and performance improvement of three-coil inductive wear
particle monitoring sensors.