There are many applications of insulation materials in electric motors, and almost all mechanical and electrical equipment now requires insulation materials. So what are their strengths and characteristics? Before revealing the answer, let's first understand the composition structure and primary information of the motor.
The basic structure of the motor: the stopping part (stator): generates a magnetic field, forms a magnetic circuit, and is mechanically supported. Air gap: An important component of the magnetic circuit and rotating part (rotor) to ensure the safe operation of the motor: induced electromotive force, electromagnetic torque, and energy transformation. The primary materials used in the production of electric motors include conductive materials (windings, commutators, brushes), insulation materials (electrically separating the live parts from grounded components such as the iron core and base, as well as live parts with different potentials), and magnetic materials (making various components of the magnetic system such as the iron core and base).
So, what role do insulation materials play in motors?
Motor insulation structure: inter turn insulation, interlayer insulation, ground insulation, and external insulation. There are three more, including filling insulation, lining insulation, and commutator insulation.
Turn to turn insulation: the turn to turn insulation of the main pole coil and the commutation pole coil, the turn to turn insulation of the armature coil, the commutation piece, the inter piece insulation, and the insulation between various wire turns of the same coil
layer insulation; The insulation between the layers of the main pole coil with layered flat winding, the insulation between the front and rear end sections of the armature winding, the insulation between the slot and the base layer, and the insulation between the coil and the base layer
Ground insulation: refers to the insulation between each winding of the motor and the base and other non charged parts, the ground insulation of the main pole coil commutation pole coil, the ground insulation of the armature winding, and the ground insulation of the commutator, which isolates the live parts of the motor from the base, iron core, and other non charged parts to avoid ground breakdown.
External insulation: The insulation wrapped around the ground insulation is primarily used to maintain the ground insulation from mechanical damage and make the entire coil robust and flat, which also plays a reinforcing role in the ground insulation
Filling insulation: filling the open space of the coil, making the entire coil firmly form a whole, reducing oscillation, and also making the coil shape regular and flat, which is conducive to wrapping ground insulation and heat dissipation
Pad insulation: Maintain the insulation structure from mechanical damage during process operations
Commutator insulation: insulation between commutator plates, insulation between commutator plate group and ground, V-shaped mica ring and mica sleeve between commutator plate group and pressure ring, multi-layer high-quality shellac plastic mica
Insulation of stator bar conductor: inter row insulation, transposition insulation, transposition filling.
Hydrogenerator rotor insulation: inter turn insulation, magnetic pole support plate, and pole body insulation.