Aviation ground power supply and aviation airborne power supply there is a big difference, whether it is the application scene, volume size, reliability and stability of the differences are as follows:

First, the application scene:

Airborne power supply is the power supply system on the aircraft, for the aircraft in the flight process of a variety of equipment and systems to provide power, including flight control systems, navigation systems, communication systems, lighting systems, etc.. It needs to meet the power demand of the airplane under various flight conditions, including takeoff, cruise, landing and other stages, while also considering factors such as weight, volume, reliability, safety and so on. For example, in the aircraft take-off and climb phase, it needs to provide stable power support for the engine and other high-power equipment; in the cruise phase, it needs to ensure the normal operation of various electronic equipment on the aircraft.

Aviation ground power supply is mainly used to provide power to the aircraft during its stay on the ground, such as when the aircraft is on the airport tarmac for overhaul, maintenance, charging and other operations. It can replace the on-board power supply on the airplane, reduce the use time and loss of the on-board power supply, and at the same time, it can also provide power support for some ground equipment.

Second, the type and specification of power supply:

There are various types of on-board power supply, the common ones are: 

Low-voltage DC power supply: The rated voltage is generally 28.5V, and the rated power is 3kW, 6kW, 9kW, 12kW and 18kW. Some small airplanes or some small electronic equipments on the airplanes may use this kind of low-voltage DC power supply.

Constant speed and frequency AC power supply: Usually 400Hz, 115/200V three-phase AC power supply with rated capacity of 20kVA, 30kVA, 40kVA, 60kVA, 90kVA, 120kVA and 150kVA. This kind of power supply system is large capacity, light weight, reliable, and suitable for aircraft with high performance and large power consumption, such as bombers, medium and long distance transportation aircraft and fighter aircraft.

Variable-speed constant-frequency AC power supply: the brushless AC engine directly driven by the aviation engine and the frequency converter constitute the main power supply, which is 400Hz three-phase AC power supply. It is mainly used in advanced fighter aircraft.

Hybrid power supply system: The main power supply is composed of low-voltage DC power supply and frequency-converted AC (sometimes constant-frequency AC) power supply. Some transportation aircraft and helicopters have a large amount of power consumption for heating and anti-icing equipments, and their work has nothing to do with the power supply frequency, so they can use variable frequency AC power, and then they will use this kind of hybrid power supply system. 

High-voltage DC power supply system: With the development of technology, a new type of power supply system, the rated voltage of 270V or so. This power supply system has the advantages of both low-voltage DC power supply system and AC power supply system, such as high efficiency, light weight, simple parallel connection and distribution, easy to realize the uninterrupted power supply, strong anti-interference ability, do not need a constant speed transmission device, and thus simple, economical and convenient maintenance, but the circuit switching devices, power conversion devices, power conversion devices and brushless DC motors, etc. are more complex.

The types and specifications of aviation ground power supplies vary according to different application scenarios and needs:

28V DC power supply: This is a common type of aviation ground DC power supply with a voltage of 28.5V (15 - 35V adjustable), which can be used for starting and energizing aircraft and on-board equipment for checking, as well as powering some ground DC equipment. For example, it can be used to power some of the aircraft's DC systems during aircraft ground overhaul and maintenance.

270V DC power supply: It is mainly used to provide high-quality external DC power supply for all kinds of military airplanes and aviation equipments in production, testing, repairing and maintenance, the output voltage is generally 270V (0 - 300V adjustable), with high stability and high reliability, commonly used in airports and aircraft manufacturing, testing, maintenance and other occasions.

400Hz IF power supply: the output frequency is 400Hz, the output voltage is usually 0 - 300VAC adjustable, it can be used to provide AC power supply for some specific equipments on the airplane, these equipments need 400Hz IF power supply to ensure their normal work. For example, some aircraft radar systems, communication systems, etc. may use this intermediate frequency power supply.

Design Requirements:

On-board power supply:

Due to the installation in the aircraft, space is limited, so the volume and weight of the power supply has strict limitations, need to meet the power requirements under the premise of as small and lightweight as possible, in order to reduce the load on the aircraft.

Reliability requirements are extremely high, because power failure during flight may jeopardize flight safety, so it must have high reliability and stability, able to work normally in a variety of harsh environmental conditions (such as high temperature, low temperature, high altitude, vibration, shock, etc.), and with redundant design and fault monitoring, diagnostic functions, so that in the event of a failure can be switched to the backup power supply in a timely manner or to take the appropriate protective measures.

Efficiency requirements are also high, high-efficiency power supply can reduce energy loss, reduce fuel consumption of the aircraft, but also reduce the power supply itself heat, improve the reliability and service life of the power supply.

Aviation ground power supply:

The restrictions on volume and weight are relatively small, because it is usually fixed on the ground to use or installed in mobile equipment (such as power trucks), unlike the airborne power supply as the aircraft load and space have strict requirements.

The same need to have a high degree of reliability and stability to ensure the safety and stability of power supply for aircraft on the ground, but because the use of the environment is relatively stable compared to the airborne power supply, so in some extreme environmental adaptability requirements may be slightly lower than the airborne power supply.

Ground power supply to meet the aircraft power needs on the basis of some special features may also need to have, such as cable voltage drop automatic compensation function to adapt to the connection of different lengths of cables; optional aircraft locking power supply control function, to ensure that the power supply is safe and accurate; with a good human-machine interface, easy for operators to operate and monitor, and so on.

Technical Requirements

Aviation on-board power supply:

As the aircraft will face various harsh environmental conditions during flight, such as vibration, high temperature, low temperature, high altitude, etc., the airborne power supply needs to have strong anti-interference ability and environmental adaptability.

The reliability requirements of the power supply are extremely high, and once a failure occurs, flight safety may be jeopardized.

In order to reduce the weight of the aircraft, the airborne power supply usually needs to adopt high-efficiency power conversion technology to improve energy utilization.

 Aviation ground power supply:

The main requirement is to be able to stably output power parameters that meet the requirements of the aircraft, such as voltage, frequency, power and so on.

It needs to have a good protection function to prevent damage to the aircraft electrical system.

For mobile ground power, but also need to have easy to operate and transportation characteristics.

 Output power and voltage stability

Aviation airborne power supply: the output power is generally designed according to the specific needs of the aircraft, usually able to meet the aircraft in a variety of flight conditions of the power needs. Due to the electronic equipment on the aircraft on the voltage stability requirements of higher, airborne power supply is usually equipped with precision voltage regulator to ensure the stability of the output voltage. 

Aviation ground power supply: the output power also needs to be matched according to different aircraft models, but generally speaking, it is larger than the power of on-board power supply, in order to meet the high power demand of the aircraft on the ground during startup and testing. The ground power supply also needs to ensure the stability of the output voltage, but the precision requirements may be slightly lower than the on-board power supply.

Through the introduction of the above content, we have a clearer perception of aviation ground power supply and aviation airborne power supply, Xi'an Exxon power supply is based on aviation ground AC and DC power supply, including 115V400Hz aviation AC power supply, 28V aviation DC power supply, 270V aviation high-voltage DC power supply, 540V aviation high-voltage DC power supply, corridor power supply, as well as power supply system integration, etc., for aircraft, airports and other power supply and maintenance to provide stable power support.