When I use Luke to search my Lucene index using a standard analyzer, I can see the field I am searchng for contains values of the form MY_VALUE. When I search for field:\"MY
I don't think you'll be able to use the standard analyser for this use case.
Judging what I think your requirements are, the keyword analyser should work fine for little effort (the whole field becomes a single term).
I think some of the confusion arises when looking at the field with luke. The stored value is not what's used by queries, what you need are the terms. I suspect that when you look at the terms stored for your field, they'll be "my" and "value".
Hope this helps,