Electrical Engineering Curriculum
Module from the Electrical Engineering Curriculum curriculum.
Module 3 - Transformers · Learning Objectives · 1. Apply IEEE C57.12.00 rating standards for liquid-filled power transformers · 2. Select dry-type (cast coil, VPI) vs oil-filled by location and cost · 3. Size taps (+/-2x2.5% typical) for source voltage variation · 4. Compute impedance-based fault current contribution · 5. Specify cooling class: OA, FA, FOA (increased forced-air ratings) · Transformer Types and Applications
| Type | Cooling | Typical Size | Location | Cost | Notes |
|---|---|---|---|---|---|
| Pad-mount liquid-filled | OA | 500-10000 kVA | Outdoor | Moderate | Utility service |
| Substation liquid-filled | OA/FA/FOA | 10-100+ MVA | Outdoor | High | Plant service |
| Dry type cast coil | AA | 30-15000 kVA | Indoor/outdoor | Higher | Electrical rooms |
| Dry VPI | AA | 75-5000 kVA | Indoor | Moderate | Low fire risk |
| Auto-transformer | OA/AA | Any | Indoor/outdoor | Lower | When ratio <3:1 |
Source: Electrical_Engineering_Curriculum_v1.xlsx · Sheet: Transformers
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