Research on the impact factors and optimisation of dust concentration measurement techniques employing oscillating balance method

Abstract Dust accumulation in industrial settings can cause dust explosions, endangering worker safety, operational security, and occupational health, including pneumoconiosis. Therefore, it is crucial to monitor the dust concentration in real time. This study optimises an oscillating balance sensor to improve the accuracy of dust concentration monitoring. We start by using an innovative, staggered coil installation method to effectively lower the magnetic coupling interference between the coils. This technique lowers the proportion of the magnetic coupling interference signal from 51% to 17%, which greatly improves the accuracy and stability of the measurements. Second, combining simulation and experiment allows one to alter the structural dimensions and materials of the oscillating element; hence, the mass sensitivity of the sensor reaches 0.624 Hz mg −1 . Finally, experiments exploring the influence of temperature on the sensor reveal that invar alloy is selected as the material of the oscillating element, while improvements to the filter membrane assembly and fixed boundary lower the overall temperature drift to 0.023 Hz K −1 . The phase-locking issue brought on by external noise is efficiently managed by the optimum sensor together with the phase-locking scheme based on an analogue multiplier. Following experimental validation, the relative error of the dust concentration measurement is no more than 5%, the steady-state error is under control at ±0.1 mg m −3 , and the measurement accuracy meets the performance requirements of the application in the manufacturing sector.