The brushless doubly fed machine (BDFM) shows economic promise as a variable speed drive or generator. The optimization of the machine and model-based control strategies both rely on machine models, and the experimental verification of these models. To date, dynamic measurements of rotor quantities have not been possible. The authors present a system of measuring rotor bar currents in real time using a Rogowski coil to detect the current and recently developed Bluetooth wireless technology to transmit the data from the moving rotor to a computer. Experimental data collected from the system are included.