This paper concerns performance of a direct torque and flux controlled 14-pole/18-slot fractional-slot concentrated-winding interior permanent magnet synchronous machine (FSCW-IPMSM) in deep flux-weakening region. For the optimum operation of the machine, voltage limit, current limit, MTPA and MTPV trajectories defined on the torque-flux plane are incorporated in the control algorithm. In the experiment, it was found that the conventional flux-weakening algorithm of DTFC is inadequate for the studied FSCW-IPMSM to deliver a satisfactory performance at high speeds. Therefore, a modified voltage control strategy was included in the algorithm to achieve the wide speed range of the machine. Experimental results verify the effectiveness of the proposed method. A very wide speed range of 9:1 was achieved for the studied FSCW-IPMSM under the proposed method.