Analysis of 12-pulse diode rectifier operating in aircraft systems with constant frequency

In aeronautical systems, the system traditionally operates with fixed frequency (400 Hz). In the More Eletric Aircraft concept, the airplanes operate with a variable frequency (360 Hz to 800 Hz), and due to increased power demand, the systems tend to use high voltage dc buses (± 270 V). This paper analyzes the 12-pulse passive rectifier to meet those specifications and the aeronautical standards with fixed frequency. Two sorts of input filter were evaluated: L and LC. A mathematical model that includes the harmonic components of the system is developed and allows to analyze the input current and the output voltage. Simulations and a prototype were developed to validate the model.