Design Engineer Track

The knowledge of 3–5 years as a transformer design engineer, structured the way industry actually trains one: four levels, ~400 guided hours, and five capstone design projects graded against real acceptance criteria — from your first 1000 kVA hand calculation to power transformers and specials.

Learn Free

Every lesson, 3D model and calculator on this track is free — mapped from the TransformerPath masterclass, tutorial and tools in the exact order a design office would teach them.

Design

Each level gates on a capstone: a realistic customer specification you must design to, by hand and with the calculator, exactly like a work assignment.

Get Certified

Submit your capstone for engineer review, receive the model answer and a marked-up critique, and earn the TransformerPath Design Engineer certificate per level.

Honest note: a course compresses the knowledge of 3–5 years — the judgment still comes from doing. That's why every level here ends in design work, not a quiz. Pair this track with time on a factory floor and a test bay whenever you can get it.
Your progress (saved on this device)0%
1

Foundations

~80 hoursequiv. months 1–6 on the job
The physics and vocabulary of every transformer ever built — you can't design what you can't calculate.
How a transformer works— Ch.1 Fundamentals + 3D Explorer8 h
Classification & specification— Ch.2 + Ch.12 Standards8 h
Core design & CRGO— Ch.3 + Core Topology 3D10 h
Windings & current density— Ch.4 + Coil Assembly 3D10 h
Insulation system— Ch.58 h
Cooling & temperature rise— Ch.66 h
Losses, impedance & efficiency— Ch.108 h
Tank & accessories— Ch.7 + Construction Guide8 h

🏁 Capstone F — Your first complete design

Spec: 1000 kVA, 11/0.433 kV, Dyn11, ONAN, 50 Hz, Z = 5%, IEC 60076, outdoor UAE ambient. Design it entirely by hand — core area and flux density, turns, conductor sizes, winding arrangement, window check — then verify against the design calculator and explain every deviation over 5%.

Acceptance criteria
  • EMF equation applied correctly; V/turn justified against the 0.4–0.5·√kVA rule.
  • Flux density 1.55–1.70 T with the chosen CRGO grade named and its loss curve cited.
  • Current density within 2.5–3.5 A/mm² (Cu) and window space factor demonstrated ≥ fit.
  • Estimated no-load and load losses within IEC tolerance of the calculator result.
  • One page explaining what you would change if the customer capitalized losses at $5,000/kW.
2

Distribution Transformer Designer

~120 hoursequiv. months 6–18 on the job
Fast, cheap iterations — where every designer earns their instincts. Oil-immersed and cast resin, plus the commercial reality of tenders.
The worked design method— Ch.9 Worked Example, reproduce it independently12 h
Calculator mastery — all three modes— TX Calculator: distribution / power / cast resin10 h
Dry-type & cast resin design— Ch.810 h
Vector groups & paralleling— Ch.136 h
Testing — routine, type, special— Ch.1110 h
Country grids & standards adaptation— Country-Based Designer, 5 countries8 h
Procurement & tendering— Ch.188 h

🏁 Capstone D — Three designs, one tender

Three graded assignments simulating a year of design-office work:

  • D1: 250 kVA, 33/0.415 kV rural unit — optimize twice: once for lowest first cost, once with losses capitalized ($4,000/kW no-load, $1,200/kW load). Quantify the design shift.
  • D2: 1600 kVA cast-resin, 11/0.4 kV for a Dubai high-rise basement — thermal class F, 45 °C ambient derating, PD considerations, dimensions to fit a 3.5 m substation room.
  • D3: Tender response — a realistic utility spec with three deliberate traps (impossible loss/impedance combination, non-standard tapping range, contradictory cooling clause). Produce a compliant offer with a deviation schedule catching all three.
Acceptance criteria
  • All guaranteed figures within IEC 60076-1 tolerances and mutually consistent.
  • D1 shows ≥ one deliberate flux-density/current-density trade-off with cost math.
  • D3 identifies all three spec traps — missing any one fails the capstone (as it would in real life).
3

Power Transformer Designer

~120 hoursequiv. years 2–3 on the job
New physics enters: short-circuit forces, impulse voltage distribution, hot-spot control, OLTC integration. This is where designers are made.
Anatomy of a power transformer— 100 MVA 3D + 500 MVA 3D10 h
On-load tap-changers— OLTC 3D Cutaway8 h
Bushings & insulation coordination— Condenser Bushing 3D8 h
Inrush & energization— Ch.146 h
Protection — differential, REF, Buchholz— Ch.1710 h
Short-circuit withstand & forces— study notes + IEC 60076-5 (guided reading; numerical methods in review pack)14 h
Impulse voltage distribution— study notes + IEC 60076-3/-4 (guided reading; α-factor method in review pack)12 h
Engineering data lab— Masterclass Data Lab8 h

🏁 Capstone P — 63 MVA grid transformer

Spec: 63 MVA, 132/33 kV, YNd11, ONAN/ONAF 60/100%, Z = 12.5% at principal tap, OLTC ±10% in 17 steps on HV neutral end, LI 550/AC 230 kV, IEC 60076 family. Deliverables: full electrical sizing, cooling stage calculation, simplified radial/axial short-circuit force estimate, complete FAT test plan with pass criteria.

Acceptance criteria
  • Impedance within guarantee tolerance across the full tap range, shown at three taps.
  • ONAN and ONAF ratings both verified thermally; hot-spot gradient stated per IEC 60076-2.
  • Force estimate uses the correct asymmetry factor and names the failure mode each force drives.
  • Test plan sequences dielectric tests correctly (a wrong order fails — as it would on a real test floor).
4

Specials & Mastery

~80 hoursequiv. years 3–5 on the job
Every special type is a variation on discipline you now own — plus the judgment layer: failures, service, and lifetime economics.
Special types — autos, converter, furnace, earthing— Ch.15 + study briefs16 h
Site, commissioning & life management— Ch.1610 h
After-sales, spares & field service— Ch.208 h
Full-course self-test— Ch.19 Glossary & Test6 h

🏁 Capstone S — Specials portfolio

Choose two of three, plus the mandatory failure investigation:

  • S1: 40 MVA autotransformer 220/132/11 kV — co-ratio benefit calculation, tertiary sizing, and why the impedance behaves differently.
  • S2: 12-pulse rectifier transformer for a 25 kA electrolysis line — phase shifting, harmonic duty, and eddy-loss derating.
  • S3: Furnace transformer, 30 MVA with 200% overload cycles — thermal design for cyclic duty and on-load voltage regulation strategy.
  • Mandatory: a written failure investigation of a supplied case (test report + oil analysis + winding resistance data) — identify the root cause and the design or process change that prevents recurrence.
Acceptance criteria
  • Each design identifies what changes vs a standard two-winding unit and why — not just the numbers.
  • Failure investigation reaches the seeded root cause with evidence chain, not guesswork.
Certificate Track

Capstone review, model answers & certificates

All lessons above are free, forever. The paid tier adds engineer-reviewed capstone grading with a marked-up critique, the full model answer for every project, the Level-3 review pack (short-circuit force and impulse distribution worked methods), and a verifiable TransformerPath Design Engineer certificate per level.

Join the certificate track →