@tomlegamer if you can log that, then its power consumption is definitely going to be highest in a defrost, by a lot. The compressor usually will use 100-200W at the most and the defrost heaters are around 500W
I myself don't know if there is any logic behind when it happens. Prior to microcontrollers, it would have just been a clock-based timer, maybe once a day. But newer fridges may have a way to detect ice buildup - there's tons of ways that could be done but I don't know particulars