VSCF aircraft electric power system performance with active power filters

A three-phase three-wire shunt active power filter (APF) is presented to regulate the load terminal voltage, eliminate harmonics, correct supply power-factor and balance the nonlinear unbalanced loads. A three-phase based current controlled voltage source inverter is used as an active power filter. The control algorithm for the APF is based on the perfect harmonic cancellation method which provides a three-phase reference supply current in phase with its positive sequence fundamental voltage component. The APF is used in the 90-kVA advanced aircraft electric power system under variable-speed constant-frequency (VSCF) operation. The generator output voltage frequency is varied from 400-Hz to 800-Hz for different loading case-studies. Non-linear DC loads are included in the simulation of the aircraft system in addition to the different passive and dynamic loads. The power quality of the studied aircraft electric system is shown to comply with the newly aircraft electrical standards MIL-STD-704F and the IEEE-std 519.