1 Department of Energy Technology, The Faculty of Engineering and Science, Aalborg University, VBN2 Power Electronic Systems, The Faculty of Engineering and Science, Aalborg University, VBN3 The Faculty of Engineering and Science (ENG), Aalborg University, VBN4 Islamic Azad University5 Islamic Azad University
Despite the wide acceptance and use of the conventional synchronous reference frame phase-locked loop (SRFPLL) no transfer function describing its actual input-output relationship has been developed so far. Arguably, the absence of such transfer function has hampered the application of SRF-PLL as a filter or controller inside the closed-loop control systems. In this letter, the transfer function describing the actual inputoutput relationship of the conventional SRF-PLL is presented. Using this transfer function, it is shown that the conventional SRF-PLL is a first-order adaptive complex bandpass filter. It is also shown that this transfer function can be useful for tuning of SRF-PLL parameters. The accuracy of this transfer function is confirmed through numerical results.
I E E E Transactions on Industrial Electronics, 2015, Vol 62, Issue 3, p. 1679-1682