Operating capabilities of a dual-inverter open-winding interior permanent magnet synchronous motor (IPMSM) drive are investigated and compared with those of a conventional single-inverter drive in maximum torque per ampere (MTPA) and field-weakening (FW) regions. To predict the performance and operating limits of the drive systems with improved accuracy, the impact of saturation on inductances and permanent magnet (PM) flux linkage values are taken into account, and core, copper, friction and windage, and solid lasses are considered in a wide speed range. Performance prediction is conducted using machine's electromagnetic parameters and losses that are obtained via finite element analysis, coupled with an optimization algorithm to find optimal operating points in MTPA and FW regions. The analytical findings are further validated against experimental results obtained from a 1-kW dual-inverter IPMSM motor drive.