as and when vs as well as

as and when

conj

  • as soon as 

as well as

conj

  • And, in addition. 

  • Used other than figuratively or idiomatically: see as, well. 

prep

  • In addition to; further to. 

How often have the words as and when and as well as occurred in a corpus of books? (source: Google Ngram Viewer )