An induction generator based auxiliary power unit for power generation and management system for more electric aircraft

In more electric aircraft (MEA) systems, the adoption of electro-hydraulic actuators (EHAs) and electromechanical actuators (EMAs) requires a power-on-demand electrical power system with regenerative power management capability. This paper proposes an auxiliary power unit (APU) for power generation and management system to supply/absorb the highly dynamic power demand/regeneration from the EHA/EMAs. The proposed system utilizes an open-end winding induction starter/generator (OEWIS/G) to create a separate DC bus for the actuators without adding significant hardware installment to the system. During the entire flight mission, the regenerative power is recovered by one side of the OEWIG terminals; meanwhile, the power delivery to the main DC network of the aircraft electrical power system can be independently controlled by using the same generator through the other side of the terminals. A closed-loop control scheme based on field oriented control and instantaneous power theory is developed to regulate both the main DC bus voltage and the electric actuation DC bus voltage simultaneously in aircraft emergency power mode.