I'm not aware of any API directly for that, but you should check out the "System Analysis Toolkit (SAT)". Basically the 
TraceEvent API and the tracelogger/traceprinter could be helpful.

Cheers,

- Malte

> I want to do automate system CPU usage. I have to extract CPU usage of system 
> from kev file to a generic file(.txt).
> Please let me know is there any API for the same.