With its headquarters in Denmark, CWS also has offices in Sweden and Germany. It will remain an independent brand under EnBW.
CWS has approximately 190 employees, generating revenues of €35 million last year, EnBW said. An estimated 50 service teams maintain 1,800 turbines across Germany and northern Europe.
EnBW said the deal would allow it to "swiftly rise to become a significant player in the fast growing area dealing with the service and maintenance of wind turbine generators".
The deal is subject to federal antitrust approval but is expected to be complete by the end of 2016, the German firm said.
"The aim is to tap the potential for new customers in the Nordics and Germany together with CWS," said EnBW.