Research on Synchronization Algorithm for Wide-Bandwidth Variable-Frequency Grid of the More Electric Aircraft

With the rapid development of aviation technology and the continuously research on the More Electric Aircraft (MEA), the wide-bandwidth variable-frequency AC generation system has gradually become the most promising option for the power supply system of MEA. However, with the continuous growth of electrification level, more and more non-linear load are utilized in MEA, witch will lead to some power quality issues such as harmonics, reactive power, and voltage imbalance. Under this situation, in order to rapidly and accurately extract the synchronization signal of the power source and achieve real-time monitoring of the operational status and key parameters of the MEA power supply system, how to improve the robustness and adaptivity of the synchronization algorithm under wide-bandwidth variable-frequency grid become an important challenge. In this paper, a frequency adaptive synchronization method (Adaptive Generalized Delayed Signal Superposition Phase-Locked Loop, AGDSS-PLL) with great robustness under adverse grid conditions is proposed based on the generalized delayed signal superposition(GDSS) operators. In this method, GDSS operators can rapidly and accurately obtain positive and negative sequence fundamental wave information under extremely distorted grid and generate two sets of pure orthogonal signals. Moreover, an extra frequency feedforward loop is added to enhance the frequency adaptivity. AGDSS-PLL and traditional methods were tested and analyzed through simulation.