More Electric Aircraft Market Size, Share & Growth

OPPORTUNITY: Development of advanced power electronic components

Aircraft manufacturers are examining novel ways of power generation and distribution at various levels of the value chain. Complex embedded digital systems, distributed architectures, and power electronics (in the starter/generation system of the main engines) are some of the technologies vying for space on forthcoming aircraft.

One of the major technological advancements that has contributed to the feasibility of a non-propulsive electric power system is the development of reliable, solid-state, and high-power density power-related electronics. At present, generator power control units, inverters, converters, and motor controllers comprise state-of-the-art silicon-based semiconductor devices that include integrated gate bipolar transistors (IGBTs). The development of advanced composition and multilayer ceramic capacitors is expected to significantly improve the power density of future inverters, converters, and motor controllers.

The increasing use of programmable solid-state devices and switching power devices in place of traditional electromechanical circuit breaker technology is expected to benefit aircraft in terms of load management, fault isolation, diagnostic health monitoring, and improved flexibility to accommodate modifications and system upgrades. Traditionally, electrical power for aerospace applications has been generated using a variable ratio gearbox-mounted wound-field synchronous machine to obtain a three-phase 115 V AC system at a constant frequency of 400 Hz. This machine, known as an integrated drive generator (IDG), is still commonly used today. However, operating experiences under the new requirements for lower cost, increased reliability, easier maintenance, and higher operating temperatures have shown that replacing the gearbox with power electronics has obvious advantages. A high-quality three-phase AC-DC conversion plus subsequent DC-AC conversion is one of the steps in achieving these objectives. The resulting system is known as the variable speed constant frequency (VSCF) system.

CHALLENGES: Significant increase in maximum take-off weight

The weight of crucial components such as batteries, electric motors, and power electronics becomes a significant challenge when moving to more electric systems, especially propulsion. One of the big issues is the energy density of current battery technology. The weight of the batteries directly affects the aircraft's payload capability, range, and efficiency. Balancing the weight of batteries becomes a challenge in more electric aircraft when compared with other electrical units such as motors and transceivers. Adding electric propulsion systems and power electronics such as inverters, rectifiers, and converters also increases weight. Although electric motors are efficient, they could weigh more than their traditional mechanical counterparts when scaled to large aircraft. Structural reinforcement for heavier components can add more weight, which may jeopardize the savings in fuel and efficiency. This is considered a huge engineering issue for more electric aircraft since the payload and range are highly prioritized during long-distance flights. Lightweight materials, advanced high-energy-density batteries, and more efficient electric systems must be achieved to overcome this challenge.