In this paper an improved power quality buck-boost converter fed permanent magnet brush less DC motor (PMBLDCM) drive is employed for adjustable speed operation of PMBLDCM. A single-phase, single-switch AC-DC converter topology based on non-isolated buck-boost converter is employed for power factor correction (PFC) and operated with voltage follower control in discontinuous conduction mode (DCM) operation for sensor reduction. This PFC controller ensures near unity power factor in wide speed range of the drive while restricting the total harmonic distortion (THD) in AC mains current within the specified limits of the IEC standard. The proposed control scheme with PFC converter based PMBLDCM drive is designed, modeled and simulated in Matlab-Simulink environment for an air conditioner compressor driven through a 2 kW, 5.2 Nm PMBLDC motor. The obtained results are presented to validate the effectiveness of the proposed control scheme for power quality improvement at AC mains.