Accurate modelling of Permanent Magnet (PM) DC motors is a prerequisite for expedient feedback design of electric-powered mobility vehicles. This paper identifies the parameters in the ideal equations for PM DC motors and considers the methods used to measure and calculate them accurately. However, the ideal PM DC motor equations' outcomes are rarely accurate compared with the actual results and measurements. The model inaccuracy arising from the existing theoretical model, which is often used in literature and by researchers, has been observed. The work discusses the method to increase the model accuracy, and analyse the model for the application in feedback design for a target vehicle. Tests have been conducted on the actual motors with a real-time data acquisition instrument. Results have been obtained and analysed to validate the improved PM DC motor model.