Abstract:

The feasibility of using the dielectric constant as an evaluation index to evaluate the quality degradation of the lubrication oil was verified through theoretical analysis and experimental approach. A glasstube sensor to detect accurately the dielectric constant of the lubrication oil and a related PWM oscillation delection circuit were developed. A monitoring system to monitor online the comprehensive properties of the lubrication oil was made up based on the abovementioned components, thus realizing to change the vehicle lubrication oil according to its quality instead of according to visual obserration or on schedule.

Key words: vehcile engineering, lubrication oil, dielectric constant, capacitance sensor, on-line monitoring system