In Smart Grid, the integration of Information and Communications Technology (ICT) systems and power systems has enabled real-time services and distributed controls, while the fusion of technologies necessitates a profound and versatile platform for the interdisciplinary research and evaluation. This article introduces a Software Defined Smart Grid testbed architecture, which integrates real-world wireless communication systems and Artificial Intelligence algorithms to provide a re-configurable framework to meet different real-time Smart Grid testbed design requirements. Through prototyping and experiments, the architecture shows great potential in addressing co-evaluation challenges of ICT systems and power systems, as well as supporting real-time Smart Grid evaluations. INDEX TERMS Artificial intelligence (AI), coevaluation, information and communications system, smart grid, software defined radio, testbed, wireless communications.