An Analytical Mechatronic Model for Series DC Motors Using Manufacturer Test Data

Direct Current (DC) Motors are one of the most common mechatronic actuators. They are important for electromechanical servo systems, drivers for battery powered appliances and tools as well as electric vehicles. Both brushless DC motors and wound DC motors are common in electric and hybrid vehicles. The series wound DC motor is commonly used for high torque vehicle applications. The literature has many papers discussing permanent magnet DC motors but a very limited number of publications on analytical models for series wound DC motors, especially motor models that fit series wound DC motor test data available in the market place. An analytical model for a series wound DC motor is developed here based on physical principles including energy conservation. The model developed will be compared with models developed by other investigators. Available commercial test data for a series motor will be used to find model parameters for the analytical model and the accuracy of this model evaluated against the original test data. The model developed displays excellent accuracy well within the accuracy of the test data available. Typical model rms deviation from test data is under 2% for the commercial series wound DC motors evaluated.