A Dynamic Analysis of Magnetic Stepping Motors

A mathematical model of the permanent magnet stepping motor is developed and experimentally verified. Linearized equations which allow the motor to be expressed in terms of a damping ratio and natural frequency are developed for a single step response. Multistep motor operation, when driven by a current source, is analyzed using phase plane techniques. Failure of a stepping motor to follow a fixed stepping rate command is analyzed. Dimensionless curves showing maximum stepping rate as a function of motor parameters and applied load torque are derived and experimentally verified.