This paper aims to develop an approach for performance calculation of an SR motor, which is suitable for use within mathematical design optimization. For this reason the requirement is to develop procedures, which are both accurate and fast. The procedures adopted here rely on flux-linkage-current-position curves of the motor. A series of tests are carried out on a test motor. The results are compared with estimations from the developed algorithms. It is shown that the current waveform, torque-speed curve, total loss and efficiency can be accurately calculated using the proposed algorithms, provided that the motor data is accurate. The computation time required is about 0.7s and in this respect much depends on the procedures used for accessing and processing the motor data.