difference between lap winding and wave winding?

Answer 1

Lap winding :
A two-layer winding in which each coil/conductor is connected in series to the adjacent coil/conductor.

Wave winding:
Armature conductors are divided into as many parallel paths as the number of poles of the generator.

Answer 2

A lap winding can be though of as a coil of wire with axial runs of the coil disposed in slots in the inner perimeter of the armature facing a rotatable field member, or rotor. The lap windings are connected together by end turns, as necessary, to form the complete winding of the armature. A lap winding is essentially a closed coil disposed in a relatively small region of the circumference of the machine.

A wave winding is an extended winding that makes progressive runs along the axis of the element upon which it is installed. The ends of the runs are connected together in progressive fashion so that the wave winding can make one or more unbroken passes about the entire circumference of the element on which it is installed.

Answer 3

Lap and wave coil differences:

In any a-c stator, the relationship between slots, connections, coil pitch, and applied voltage typically results in multiple turns per coil. The number may range between 4 and 20. Extremely large low-voltage machines, or small motors at unusually high voltage (such as 60 hp at 4,000 volts) can fall outside that range, but they will be rare.

Such multi-turn construction is simple for a diamond coil. Whether a single strand or several, the conductor is wound flatwise, one turn over the top of the one before, into a loop (sometimes called a shuttle or skein) that is then consolidated and spread into diamond form. Although the conductors are bent on edge somewhat in the coil shaping, the stress is not severe.

In contrast, the wave winding does not readily lend itself to joining multiple turns at the end of one coil to corresponding turns at the beginning of the next. Hence, most wave-wound coils consist of only one or two turns. Each can be put in place through the slot opening, undergoing less distortion and insulation stress in the process because the two open "legs" of each coil are free to move.

Because machine losses and temperature rise dictate filling as much of the slot with copper as possible, the one- or twoturn coil conductor must be much deeper than any single turn in a diamond coil (again, see Figure 5). Multiple conductors per turn are possible (though seldom more than two), usually side by side in the slot although one can sometimes be above the other.

That highlights the second limitation on wave winding usage in a stator. A conductor this deep, not readily broken up into numerous strands insulated from one another, will generate unacceptably high eddy current loss at line frequency. In a diamond coil, individual turn conductors deeper than about 0.2 inch are normally divided into smaller strand depths. An inch-deep conductor would exhibit I^sup 2^R loss up to seven times that predicted from its d-c resistance alone.

In a rotor, this is not a problem. Eddy current losses are frequency-dependent. Because the frequency within a rotor at full speed is only a small fraction of that in the stator, where it remains at the supply system value, such losses in rotor conductors will not be significant.

Deep conductors (often an inch or more) must be bent on edge to form the coil "knuckle" at the end opposite the connections. This requires specialized tooling.

Some wave coils are of the "push through" type. Rather than being preshaped to the configuration of Figure 2, the open ends of each coil are manually spread outward into position after the coil has been pushed through the slots from the knuckle end. That avoids having to drop the coil in through rotor slot openings, which may not be practical for some conductor arrangements.

Answer 4

in lap winding A=P(parallel plates)
in wave winding A=2...