Contactless Capacitance Sensor for Anti-overflow in Unattended Cooking Process

Abstract

The unattended cooking is the new trend in the field of cooking products. In the cooking process, overflow of food is the main challenge for unattended cooking. The shortcomings of existing methods are response delay and omission of detection, as well as misjudgment of detection. In this work, we integrated a contactless capacitance sensor into induction cooker to rapidly detect the boiling characteristic signal for anti-overflow. The contactless capacitance sensor module and magnetic-induction heating platform were constructed into a closed loop feedback control system to modify the heating power for avoiding overflow. The delay time was less than 300ms and the cost of contactless capacitance sensor module was 1.5 dollar. In 30min cooking process, it existed high accuracy (SNR = 3) without any overflow and the splashing liquid volume was less than 5g. Due to its low cost, good repeatability and reliability, it can be potentially applied in the field of intelligent home appliances.