Điện và Điện tử HK 1-23

External power is used for aircraft when:

• During flight

• On ground and during flight

• On ground

Differential protection circuit is used to:

• Detect short circuits (without circuit breaker)

• Detect open phase in AC distribution systems.

• Detect open phase in AC distribution systems.

• Detect open phase in AC distribution systems.

Main advantages of parallel operation are:

• Share loads between generators and No power interrruption

• No power interrruption

• Share loads between generators

• Isolated power supplies.

On an aircraft equipped with an electrical flight control system such as A320, Main

DC Power distribution works:

• In parallel operation

• In parallel or isolated operation

• In isolated operation

When two IDGs in twin engine aircraft fails, DC EMER bus is supplied by:

• Battery only

• TR2 via DC bus2 or ESS TR via DC ESS bus

• TR1 via DC bus1 or ESS TR via DC ESS bus

The fuction of Static Inverter is

• Convert 115V AC to 28 V AC

• Convert 115V three phases to 28V DC

• Convert 28V Dc to 115 V AC

• Convert 24V Dc to 115 V AC

If generator load current in phase A is zero and in normal range for the other two

phases, the GCU triggers a protection circuit of:

• Open phase

• Short circuit

• Undervoltage

• Overvoltage

GCU protection function can be divided into:

• 03 groups

• 05 groups

• 02 groups

• 04 groups

If the CSD fail, the generator will be affected:

• voltage

• frequency

• current

• phase

GCU for the emergency generator provides the main functions:

• Both parallel and isolated operation

• For isloated operation

• For parallel operation