Electrical machines are devices that convert electrical energy into mechanical energy (motors) or vice versa (generators). The stator is an essential component of electrical machines and is responsible for producing a rotating magnetic field. There are several types of stator constructions used in different electrical machines, such as:
Salient Pole Stator: In this construction, the stator has projecting poles with concentrated windings around them. These poles are unevenly spaced, giving the stator a "salient" or non-uniform appearance. This type of construction is commonly used in synchronous generators and motors.
Non-Salient Pole Stator: Also known as round rotor or cylindrical rotor construction, the stator has uniformly distributed windings and smooth surfaces. The poles are evenly spaced, providing a more symmetrical appearance. Non-salient pole stators are commonly used in induction motors and some types of synchronous machines.
Wound Stator: In this type of construction, the stator windings are made up of coils of insulated wire wound around the stator core. The winding configuration can be either concentrated or distributed, depending on the application.
Permanent Magnet Stator: In machines with permanent magnet stators, the stator contains permanent magnets that create a fixed magnetic field. This type of construction is common in permanent magnet synchronous motors and some brushless DC motors.
Homopolar Stator: In homopolar machines, the stator windings are arranged in such a way that they produce a magnetic field parallel to the axis of rotation. These machines have a unique design and are mainly used in high-power applications, such as large-scale power generation.
Hybrid Stator: Some modern electrical machines may use a combination of different stator constructions to achieve specific performance characteristics or to optimize efficiency. These hybrid stator designs are typically customized for specific applications.
The choice of stator construction depends on various factors, including the type of electrical machine, the desired performance characteristics, efficiency requirements, and the intended application. Each construction has its advantages and limitations, and engineers select the most suitable stator design based on the specific needs of the electrical machine.