askelmoottorin

An askelmoottori, often translated as a stepper motor or step motor, is a brushless DC electric motor that divides a full rotation into a number of equal steps. The motor's position can be controlled without a feedback sensor, as long as the motor is run within its specified torque and speed limits. The number of steps per revolution is determined by the motor's design. These motors are widely used in applications requiring precise angular positioning, such as robotics, 3D printers, CNC machines, and various industrial automation systems.

There are several types of stepper motors, including permanent magnet, variable reluctance, and hybrid. Permanent magnet stepper motors use a permanent magnet rotor. Variable reluctance stepper motors have a rotor made of a soft iron core with teeth, and the stator poles are electromagnets. Hybrid stepper motors combine features of both permanent magnet and variable reluctance types, offering higher torque and better precision.

Stepper motors operate by energizing the motor's coils in a specific sequence. Each sequence of coil energization causes the rotor to move a discrete step. This step-by-step motion allows for open-loop position control, meaning the motor controller can command a specific number of steps, and it is assumed the motor will reach that position. However, if the load torque exceeds the motor's holding torque, or if the motor is commanded to move too quickly, it can lose steps, leading to position errors. Therefore, for critical applications, feedback mechanisms might still be employed to ensure accurate positioning.