Feasibility study of frost layer recognition based on color sensors

Aiming at the problem of false defrosting in the heating condition of air-source heat pumps, a defrosting control method of air-source heat pumps based on color sensors is proposed. According to the working principle of the color sensor, the hardware and software are designed, and the feasibility of frost layer recognition is verified by experiments. The results show that with the growth of the frost layer, the output R, G and B values gradually increase. The values of R, G and B before frosting are 61, 58 and 56, respectively. After 20 minutes, the values of R, G and B are 114, 108 and 106, respectively, which can effectively identify the frosting condition on the surface of the heat exchanger. It has potential value for future applications to defrosting control of air-source heat pumps and related heat exchanger defrosting.