Types of Electric Motors
Different types of electric motors have different properties. For example, one type is designed to move quickly and accurately, while another one is designed to provide continuous motion without gear shifting. The type of motor you need depends on your application, and there are three types of electric motors: a synchronous motor, a brushless brushed motor, and a stepper or servo motor. For fast, continuous movement, you’ll need a synchronous motor, while a brushless brushed motor will be best for precise positioning.
The speed of an electric motor depends on the frequency of its power supply and the number of poles in its stator winding. Typical power supplies in the U.S. are 60 Hz, and a synchronous speed of 3,600 rpm is possible. If the wire is attached to a magnet with a north pole, then it will attract to that pole. This “kick” will cause the wire loop to rotate.
The starting current of a synchronous motor is limited by its flux leakage path. A motor running on full voltage is usually limited to four to seven times its rated current. Starting torque is usually in the range of 1.75 to 2.5 times its rated value. This method is called a reduction in starting voltage. The electric supply current, however, remains the same. Consequently, it is safe to use a voltage reduction method with an electric motor.