36V Aviation Power SupplyThe aircraft power system consists of the main power, emergency power, and secondary power, sometimes including auxiliary power as well. The main power refers to the power generation system driven directly or indirectly by the aircraft engine, typically with one engine powering one or two generators.
When the engine is not operational (such as during ground tests), the main power also fails to work, and the auxiliary power supply takes over at this point. The aircraft's battery or auxiliary power unit (a power system comprising a small on-board engine, generator, and hydraulic pump, etc.) is a common source of auxiliary power. In the event of a main power failure during flight, the battery or emergency generator becomes the emergency power source.
Electrical loads on airplanes can be categorized into the following types based on their use:
1. Electric Mechanism
Electric motors are primarily used in aircraft control systems, such as flaps, rudders, force arm adjustments, and landing gear retraction mechanisms, as well as in motors driving oil pumps, valves, and others, accounting for approximately 30% of the total load. This includes both DC electric motors and AC asynchronous electric motors.
2. Heating and Anti-icing Loads
Heating and de-icing loads account for about 40% of the total load on large transport aircraft. These loads have no special requirements for the type or quality of electricity, and can be powered by direct current, constant-frequency alternating current, or variable-frequency alternating current.
3. Electronic Devices
Electronic devices are powered by a constant-frequency AC power supply, as these devices play a crucial role in flight safety. Therefore, there is a high demand for the quality of the power source.
4. Lighting Equipment
Direct current (DC) or variable-frequency alternating current (VAC) can be used to power the cabin's lighting equipment, which requires a relatively stable voltage.
Different aircraft types and flight missions result in varying power consumption. The peak power usage for transport aircraft occurs during winter night flights, when lighting, heating, de-icing, and domestic electrical equipment demand high power.
