This paper presents the development of a position sensorless controlled synchronous reluctance motor (SynRM) drive. First, the basic vector controlled SynRM drive is established, including power circuit, sensing and commutation schemes. Then the high-frequency injection (HFI) based rotor position estimator is developed to yield the rotor position for making the vector control. After comprehending the effects of armature current ripples on the rotor position estimation characteristics. The proper voltage and varied frequencies of the injected signal are set to enhance the dynamic and static performances of the position sensorless controlled SynRM drive. Some measured results are provided to verify its driving performances, including starting, acceleration/deceleration and reversible running characteristics.