TRANSFORMER COIL WINDING

                                    TRANSFORMER COIL WINDING

Copper and silver alloyed copper magnet wire—or continuously transposed copper cable—is used for the winding conductors on all Waukesha® power transformers. Continuously transposed copper cable is used to minimize losses and hot-spot temperatures and to produce a more compact winding with improved short-circuit performance.

All windings are circular, concentric type and provide maximum through-fault withstand capability. High voltage and low voltage windings use a continuous-disc or helical winding design. This construction provides maximum strength and short-circuit withstand capability, increased predictability and lower hot-spot temperatures for loading and overloading.

Multiple conductor continuous disc and helical windings are transposed throughout the winding to minimize circulating current losses. State-of-the-art design techniques are used to provide maximum impulse strength in the windings and to minimize voltage stresses. Special design consideration is also given to the line end discs to control voltage stress distribution.

Ampere-Turn balancing techniques are used to minimize radial leakage flux and to minimize axial short-circuit forces. In order to ensure short circuit performance, windings are manufactured to meet stringent design tolerances for coil winding electrical height, tap locations and spread section locations.

Cooling ducts are formed between discs in the continuous-disc and helical windings by keyed radial spacers made of special high-density pressboard insulation. These spacers are aligned in column to provide axial support for the windings and high short-circuit strength.

All windings are manufactured in a clean winding environment. This isolated “factory within a factory” is humidity and temperature controlled 24 hours a day with controlled access to minimize contamination.