There is no officially supported way to do that. You can "reverse engineer" what Power BI is doing and fetch/curate the data yourself, but there are some drawbacks with such approach. First, as mentioned already, it's not in any way supported by Microsoft. Second, it only supports user context, so you're stuck with interactive authentication and limited automation. There is no documentation on the available endpoints and methods, so you have to dig this out of the PowerBI model. And, the data model itself needs to be rebuilt, if you want to get something meaningful.
Anyway, if you want to try this approach, here's the info you need. Use the built-in "Microsoft PowerQuery For Excel" application with ID a672d62c-fc7b-4e81-a576-e60dc46e951d and RedirectURI of https://preview.powerbi.com/views/oauthredirect.html to obtain an access token. Only user context is supported, and you can use the https://api.interfaces.records.teams.microsoft.com/.default scope.