It’s difficult to detect whether the edible vegetable oil is adulteration.According to the characteristics that one kind of oil’s permittivity is different from others

a capacitive sensor is designed for oil quality detection.The equivalent circuit of the sensor is established to analyze the impact of sensor structure on capacitance detection.The sensor is rod-shaped

and the probe of plate capacitor is sensing unit.The AD7745 chip is used to detect the capacitance change due to different oil quality acting as medium.The detecting result of the sensor is displayed digitally

and is output through the I2C serial bus port.Experiment shows that the sensor can distinguish quickly whether the oil contain adulteration or not to above 3 % edible vegetable oil

and its repeatability is prior to 0.2 %.