How to make Power BI Service export data only in csv format?

Anonymous 

Not sure it is possible

Hi Anonymous ,

For reports,  we can't export the report only as a .csv file.  You could pin the visuals to dashboards. Then we can export it to CSV.

Reference:

Export data from a Power BI dashboard 

If this can't help you, you could vote up the idea to get the feature fixed. And you could submit a new one as well.

Exporting data when used within Apportal 

https://ideas.powerbi.com/forums/265200-power-bi-idea