The invention relates to an oil
abrasive particle detecting sensor and a design method thereof. The design method comprises, after a sensor framework is determined, calculating the relation curve between
magnetic field intensity B and number of coil turns n by formula, take the n, which corresponds to the maximum value of the B, as the number of turns of an
induction coil and two exciting coils. According to the oil
abrasive particle detecting sensor, the number of coils of every coil is determined according to the design method; the output end of the
induction coil is connected with a modulation and
demodulation circuit, which is sequentially connected with a pre-amplification circuit, a low-pass filter, a high-pass filter and an
oscilloscope. For
signal output components, the oil
abrasive particle detecting sensor provides the modulation and
demodulation circuit comprising the pre-amplification circuit, the low-pass filter and the high-pass filter. The design method of the oil abrasive particle detecting sensor helps design the number of turns of the
induction coil, which can maximize
signal output amplitude, and under the dimension of the
mass-produced sensor framework, the induction coil can be conveniently mounted on various oil-lubricated engines. The oil abrasive particle detecting sensor can accurately obtain abrasive particle associated information and be applied to measuring
metal abrasive particles only with a
diameter of 500 mu m.