I have a rainfall data from 1961 to 2015 for each day of this years. I need to create a raster for each day with this configuration.

Do you know how to automate this using this plugin and python?
I was able to provide a solution to your problem in another answer of the following existing question:
How to compute an interpolation raster from the python console in QGIS
This solution is based on the usage of the QGIS interpolation classes (QgsInterpolator, QgsTINInterpolator, QgsIDWInterpolator, QgsGridFileWriter) in a short python script. I hope it poses an easy solution for you!