Electrical System of Aircraft is an indispensable part of any modern avionics module of avionics. The most stringent requirements apply to the stability and reliability of uninterruptible power supply of airplane. From the operation of power systems depends operation of all Aircraft system.
Uninterruptible power supply systems of Aircraft can be divided into three main groups:
1) sources of electric energy converters with their control equipment;
2) transmission systems and distribution of electric energy;
3) consumers of electricity.
For the purposes of avionics modern aircraft Electric power supply systems provide AC (Alternating Surrent - AC) 115/36 in the frequency of 400 Hz and a DC (Direct Current - DC) - 27/28/270 in [76].
The main advantages of using direct current uninterruptible power supply onboard Aircraft
- DC generators fed batteries in flight;
- While changing the rotational speed of the central part of the engine is very easy to adjust the consistency voltage;
- Ease of building systems using parallel generators.
The main disadvantage in applying DC uninterruptible power supply is that electricity DC difficult to convert to other types.
The main advantages of AC:
- Ease of building systems transformation tension;
- AC generators and motors are cheaper and lighter;
- Simple voltage transformation in any other.
Alternative current uninterruptible power supply
The main disadvantages of using AC:
- The need for special equipment that ensures the stability of the motor shaft speed to obtain a stable frequency;
- Inability to use batteries as a backup power source;
- The need for a separate generator to provide power supply of to the engine idle conditions.
PC power systems can be divided into three main types of construction:
1. DC generator as the main source of electricity. For AC converters use a DC / AC.
2. alternator as the main source of electricity. The generator is connected to the drive motor PC. To develop DC using rectifiers AC / DC.
3. Mixed system power. Used generators AC and DC currents.