The Development Of Dehumidifier Device Used In The Outdoor Terminal Box Of Substation Based On Semiconductor Refrigeration Technology

The state of safe and stable operation of the auxiliary equipment "terminal box" in the substation is the foundation of reliable power supply. But in the south of China, the relative humidity is heavy and last for a long time in rainy season. The insulation of the terminal box will be reduced and even worse when discharge phenomenon happened on the insulation surface if they work in such bad environment. In this paper, a dehumidifier device is developed by using the semiconductor refrigeration for this kind of special damp environment of south China. The wet air in the terminal will condense quickly on the cool surface of the dehumidifier, and therefore the air moisture content will be reduced thoroughly based on the principle of cooling dehumidification of semiconductor refrigeration. In this paper, two controlling methods of dehumidifier device is considered. One is using the AVR single-chip microcomputer, monitoring external relative humidity all the time. The other is using the voltage comparator based on the output linear characteristic of the relative humidity sensor. The two controlling methods are both simple and have their own characteristics. The experiments proved that the device by using the two controlling methods can effectively reduce the relative humidity of wet air. This dehumidifier device based on semiconductor refrigeration technology is small and will have a good application prospect.