Sept 22 (Reuters) - The Federal Reserve will release research “soon” examining the costs and benefits of a central bank digital currency, or CBDC, Fed Chair Jerome Powell said on Wednesday. “We’re working proactively to evaluate whether to issue a CBDC and, if so, in what form,” Powell said in a news conference following the conclusion of the Fed’s two-day policy meeting. The ultimate test that will apply, he said, is if there are “clear and tangible benefits that outweigh any costs and risks.” (Reporting by Jonnelle Marte Editing by Paul Simao and Leslie Adler)