A motor is a device that converts electrical energy into mechanical energy.  It operates based on the principles of electromagnetism.  When electric current flows through a coil of wire placed within a magnetic field, it generates a force that causes the coil to rotate, thereby producing mechanical motion.  Motors are widely used in various applications, including industrial machinery, household appliances, vehicles, and robotics, among others.  They come in different types, such as AC motors (alternating current), DC motors (direct current), stepper motors, and servo motors, each suited to specific purposes and requirements.


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Motor Design Classification

  • DC Motor  -  A type of electric motor that operates on DC electricity.  It converts electrical energy into mechanical energy through the interaction of magnetic fields.  DC motors operate on power where the current flows in one direction such as the power generated from batteries or AC power sources that are rectified to direct current.  The two major categories of DC motors are brushed and brushless, for more information on specifics of brushed and brushless motors, visit here:
    • Brushed  -  A type of DC electric motor that operates using brushes and a commutator.  It's one of the simplest and most common types of electric motors, widely used in various applications such as household appliances, power tools, toys, and automotive systems.  This motor has permanent magnets inside its outer body with a rotating armature inside.  The permanent magnets are stationary and are called the stator.  The rotating armature contains an electromagnet and is called the rotor.
      • Shunt Wound
      • Separately Excited
      • Series Wound
      • Compound Wound
      • Permanent Magnetic
      • Servomotor
      • Universal
    • Brushless  -  An electric motor that operates on DC and does not rely on brushes and a commutator for operation, unlike traditional brushed DC motors.  Instead, BLDC motors use electronic commutation to control the stator windings, making them more efficient, reliable, and maintenance free compared to brushed DC motors.  Like a brushed motor, a brushless motor works by alternating the polarity of windings inside the motor.  It is essentially an inside out brushed motor, which eliminates the need for brushes.  In a brushless DC motor, the permanent magnets are fitted to the rotor, with the electromagnets on the stator.  An electronic speed controller regulates or commutates the charge to the electromagnets in the stator, to enable the rotor to travel through 360-degrees.
  • AC Motor  -  An electric motor that operates on AC electricity.  Unlike DC motors, which operate on direct current, AC motors rely on the changing polarity and direction of the electrical current to generate the rotating magnetic field necessary for producing mechanical motion.  These motors are powered by single or three phase alternating currents. The electromagnetic field in the stator reacts with the rotor and causes the motor to rotate at a synchronous speed to match the frequency of the AC current.  AC motors are efficient, durable, quiet, and flexible, which makes them a viable solution for many power generation needs.
    • Induction Motor  -  An induction motor is a type of AC electric motor.  It's one of the most commonly used types of electric motors due to its simplicity, reliability, and robustness.  Induction motors operate on the principle of electromagnetic induction.  Almost all induction motors run at essentially constant speed from no-load to full-load conditions.  The speed of induction motors depends on the supply frequency and hence these motors are not easily adapted to speed control. Induction motors are simple and rugged in construction, less expensive, easy to maintain, and can be designed and produced with characteristics to suit most industrial requirements.
      • Squirrel Cage  -  Also called an induction motor, is a type of AC electric motor widely used in various applications due to its simplicity, reliability, and robustness.  The name "squirrel cage" refers to the rotor design, which resembles a rotating cage.  The shaft is connected to the rotor which looks like a cage and it works on the principle of electromagnetism.  So it uses the electromagnetic induction effect to convert the electrical energy into rotational energy.
        • Single Phase
          • Shaped Pole
          • Split Phase
            • Capacitor Start
            • Capacitor Start (Permanent -Split Capacitor)
            • Capacitor Start/Run
            • Resistance Start
        • Three Phase
          • Design A
          • Design B
          • Design C
          • Design D
      • Wound Rotor  -  Also called a slip ring motor or wound rotor induction motor, is a type of AC electric motor that shares similarities with squirrel cage induction motors but has a distinct rotor design and additional features for enhanced control.  A wound rotor induction motor is defined as a special type of 3 phase AC induction motor designed to provide high starting torque by connecting an external resistance to the rotor circuit.  The motor’s rotor is a type of wound rotor.
        • Single Phase
          • Repulsion
            • Repulsion Start
            • Repulsion Induction
        • Three Phase
          • Three Phase Round Rotor
    • Synchronous Motor  -  It is another type of AC electric motor, distinct from induction motors.  Unlike induction motors, synchronous motors operate at a constant speed that is precisely synchronized with the frequency of the AC power supply.  The rotation of the rotor (or shaft) is synchronized with the frequency of the supply current.  That is, the rotation period of the rotor is equal to the rotating field of the machine it is inside of.
      • Single Phase
        • Reluctance
        • Sib-Synchronous Reluctance
        • Hysteresis
        • Stepper
          • Permanent Magnet
          • Variable Reluctance
          • Hybrid
      • Three Phase
        • Permanent Magnet
        • Synchronous Reluctance
        • Hysteresis
        • Synchronous Induction
    • Linear Motor  -  A type of AC electric motor that produces linear motion instead of rotational motion.  It operates on the same principles as traditional rotary AC motors but is designed to generate linear movement along a straight path.  In a traditional electric motor, the rotor spins inside the stator, in a linear motor, the stator is unwrapped and laid out flat and the rotor moves past it in a straight line.  Linear motors often use superconducting magnets, which are cooled to low temperatures to reduce power consumption.
      • Induction
      • Synchronous

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