Motor-CAD is a thermal analysis package for electric motors and generators, developed and sold by Motor Design Ltd. It was initially released in 1999. Modules are available for brushless permanent magnet motors (BPM), outer rotor BPM motors, induction motors, permanent magnet dc machines, switched reluctance motors, synchronous machines and claw pole machines. A wide range of housing types can be modelled. Thermal analysis of electric machines is regarded as a more challenging area of analysis than electromagnetic analysis in the construction of the model and the accuracy achievable.