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Upskill / Aircraft Maintenance / Electrical power systems: generation, distribution and protection

Electrical power systems: generation, distribution and protection

Generators, conversion, batteries, bus architecture, circuit protection and EWIS on transport aeroplanes, under CS-25 and 14 CFR Part 25

By Aerospace Garage Desk · Practitioner · 50 minutes · 24 narrated pages

What you will be able to do

  • ✓ Describe the architecture of an aircraft electrical power system under ATA 24, the AC and DC supplies used, and the CS-25 and 14 CFR Part 25 paragraphs that certify it.
  • ✓ Explain how integrated drive and variable-frequency generators, control units, APU and external power, batteries and the ram air turbine supply power in normal and emergency conditions.
  • ✓ Compare lead-acid, nickel-cadmium and lithium-ion batteries, their thermal runaway hazards and special conditions, using the NTSB findings on the 2013 Boeing 787 APU battery fire.
  • ✓ Analyse bus architecture and load shedding, and calculate bus loads and battery-only endurance for normal and failure cases.
  • ✓ Apply circuit protection, EWIS and bonding requirements, including continuity and insulation-resistance checks and protect-clean-as-you-go practice.
  • ✓ Apply safe isolation, wiring-diagram troubleshooting and MEL relief to make sound maintenance and dispatch decisions on electrical defects.

Course content

Session 1 · Aircraft electrical power: the system and its rules

1.1

  1. Electrical power on a modern aeroplane · free preview
  2. AC and DC: the voltages aircraft use
  3. The certification basis
  4. Worked example: a load analysis on two DC buses
Session 2 · Generating the power: IDG, VFG, APU and emergency sources

1.2

  1. Engine-driven generators: IDG and variable frequency
  2. Control, protection and the other sources
  3. Emergency power: RAT, batteries and the rules
  4. Worked example: IDG high oil temperature, service or replace?
Session 3 · Converting and storing: TRUs, inverters and batteries

1.3

  1. Transformer rectifiers, inverters and converters
  2. Lead-acid and nickel-cadmium batteries
  3. Lithium-ion batteries and special conditions
  4. From the investigation file: the Boeing 787 APU battery fire, Boston 2013
Session 4 · Distribution: bus architecture, load shedding and emergency power

1.4

  1. Bus architecture: who feeds what
  2. Load management and load shedding
  3. The emergency configuration
  4. Worked example: how long will the batteries last?
Session 5 · Circuit protection, wiring and bonding: EWIS in practice

1.5

  1. Circuit breakers, fuses and arc-fault protection
  2. EWIS: wiring as a system
  3. Bonding, connectors and the faults wiring causes
  4. Worked example: continuity and insulation-resistance check
Session 6 · Working safely, troubleshooting and MEL relief

1.6

  1. Working safely: de-energising and lock-out
  2. Troubleshooting with wiring diagrams
  3. MEL relief for electrical items
  4. Worked example: dispatching with one generator inoperative

Who this course is for

Upskill courses are for professional development and are not approved by any aviation authority. Learner Terms

Course content © Aerospace Garage Limited. All rights reserved.