The SharePoint Project name will come as a WSP name, some time when we need to rename the WSP file.
In Visual Studio->Navigate to Package->Click on the Package.package
Previous I am getting the WSP with name SharePointSolution1.WSP.
Now I want change the Name to DotNetSharePoint
Now I can get WSP name as DotNetSharePoint.WSP
Once it’s done, restart the visual studio get the WSP file with modified name.