Abstract:It is difficult to achieve fullflow lubricant monitoring by using the traditional single excitation wear debris sensor. Hence, this paper designs an inductive wear debris monitoring sensor based on the multiexcitation structure. Multiple excitation structures are placed in the circumferentialdirection ofthe flow channel, which expand thedetection range.In thisway,the debris detection within the whole diameters canbe realized.By formulatinga threedimensionalfinite elementmodel,thestaticmagnetic fieldandtransientcharacteristics of the induction coil are analyzed. The relationship between the number of excitation structures and the uniformity of the yz plane circumferential magnetic field has been revealed. Meanwhile, the magnetic pole shape of the sensor is optimized. By using the generated signal, experimental results show that intensity and direction of excitation current, and the number of excitation structures have directly influence on the inductive signal. Results verify that the number of excitation structures is an important influencing factor on the effective detection range of the sensor. And the results of inputting wear debris experiment show that the 13 μm ferromagnetic debris in a 40 mm diameter flow channel under the condition of lubricating oil circulation can be detected.