Electrical Power

Question 1

What is the the voltage of the AC system?

Answer 1

115v

Question 2

How many phases are generated by the AC generators?

Answer 2

3

Question 3

What produces the AC power for the aircraft and where would they be located?

Answer 3

Integrated drive generator

Located in the engines

Question 4

What DC voltage is produced by the batteries?

Answer 4

24v

Question 5

What is the main source of DC power for an aircraft?

Answer 5

2 transformer rectifier units that convert 115 AC power.

Question 6

How long can the batteries supply standby power for?

Answer 6

90 minutes

Question 7

What controls and regulates the voltage for the generator side of the IDG?

Answer 7

Generator control unit

Question 8

What are the main uses of electrical power?

Answer 8

Electronics
Lighting
Producing mechanical power
Electrical heating

Question 9

What is the difference in phase angle between the 3 AC phases?

Answer 9

120 degrees

Question 10

What is the basic theory behind AC generation

Answer 10

By rotating magnet inside a stator, an AC voltage is induced in the stators coil

Question 11

How is an IDG generator arranged?

Answer 11

The magnet is in the centre and 3 separate coils are positioned around it with 120 degrees between each one.

Question 12

Where on an engine would the IDG be found?

Answer 12

Connected to the accessory gear box

Question 13

What are the subsystems for electrical power?

Answer 13

Generation

Distribution

Question 14

What is a static inverter used for?

Answer 14

Converting DC power to AC power to supply necessary systems for a safe landing

Question 15

What sources of AC power are there?

Answer 15

Ground power
IDG
APU generator 
Emergency generator (RAT)
Static inverter

Question 16

How much of the total electrical power is used by AC consumers?

Answer 16

95%

Question 17

What is the reaming power for the DC consumers used for?

Answer 17

Electronic equipment
Static inverter
Control and monitoring parts of other user groups

Question 18

What do the batteries power?

Answer 18

Emergency distribution
APU starting
Engine starting if starter generators are used?

Question 19

What are the 3 types of electrical distribution?

Answer 19

Main power
Emergency power
Essential power

Question 20

What does the emergency distribution power?

Answer 20

Systems that are essential for landing safely

Question 21

What are the 4 types of electrical consumers?

Answer 21

Single phase
3 phase
Large loads
Voltages other than 115

Question 22

What is load shedding and what users does it affect?

Answer 22

Load shedding cuts off large load users (galley) to improve the reliability of power relays and prevents an overload