Caffe Power Operator is not supported?

I'm trying to use rknn toolkit to convert a Caffe mode. However, it shows an error" Unknown caffe layer xxx, op is power, please REMOVE it from prototxt if possible.". Power operator should be a standarad operator provided by Caffe (https://caffe.berkeleyvision.org/tutorial/layers/power.html). Is it supported by rknn toolkit? Thanks!

不知道可否帮忙看一下，caffe power operator是不是被支持？