if you are using Photoshop CC June 2014 You can get benefit using Extract assets from layers by naming folder group .png this will ensure saving a copy of all the layers and it's sun as assets.
what I mean: you can save your PSD normally while the layers of your logo grouped in a folder layer named XXXX.PNG so you may save PSD normally in the same time you will export all group layers under a specific folder or individual layers as flatten PNG file.
please see this new feature here