The analysis of input ripple current characteristics of Aviation Static Inverter

As a typical load of aircraft power system, Aviation Static Inverter (ASI) brings about undesirable low frequency ripple current on the aeronautic DC bus, which seriously deteriorates the power quality of aeronautic grid. In this paper, based on the Double-Fourier switching function method, the input current of the inverter unit is analyzed. The corresponding expressions of the DC component, the second harmonic current, the m-th harmonic current with regard to the carrier frequency, and sideband harmonic current are given. In addition, the equivalent circuit model of the second harmonic current spreading to the high voltage DC bus is derived. This model reveals the generation and propagation characteristics of low frequency input ripple current of ASI and its impact factors. Simulation and experimental results are shown to validate the theoretical analysis.