OK that sounds like it could cause a problem with the ps3. The Ps3 uses a lot of juice. I have heard about a trucker who used a power inverter in his truck for the PS3 and it nearly caught fire. I think the PS3 runs on 200wats continuously. i am not sure how inverters run their power. but the reports i have looked into for you suggest its not a good idea.
leave this with me for around a week and i will see what i can dig up for you.
one more thing where are you based? i am U.K i ask because it may be different with diff places. i.e uk power outlet differs from the usa.