What type of air gaps are maintained between the poles and the armature for optimal operation?

For optimal operation in electrical machines, maintaining comparatively small air gaps between the poles and the armature is essential. A small air gap allows for better magnetic coupling between the stationary and rotating components, which enhances efficiency and performance. The strength of the magnetic field is inversely proportional to the size of the air gap; a smaller gap results in a more concentrated magnetic field, which contributes to a higher induced voltage in the armature.

Additionally, smaller air gaps reduce flux leakage, minimizing losses and ensuring more effective energy conversion. When air gaps are large, the magnetic flux weakens significantly, leading to reduced efficiency and potential operational issues such as overheating and increased losses. Therefore, for optimal operation and to maximize the performance of the electrical machine, it is crucial to maintain a comparatively small air gap.