Design of a real-time rotor inertia estimation system for DC motors with a personal computer

Various traditional measurement techniques of moment of inertia were examined. Two computer-based measurement methods using the motor's torque constant, back EMF (electromotive force) constant, mechanical time constant, and armature resistance with straightforward formulations were investigated. A PC-based inertia measuring unit was designed by using a multifunction interface card for signal processing and acquisition circuits. This low-cost inertia computation and measurement system can be used to assist in modeling and controlling DC drives in real-time. The system can also be integrated into an existing DC motor measurement or testing laboratory. Experimental results are presented.<>