Modeling and Tuning of an Improved Delayed-Signal-Cancellation PLL for Microgrid Application


An improved delayed-signal-cancellation (DSC) phase-locked loop (PLL) is proposed for microgrid applications. The conventional DSC-PLL suffers from phase and frequency measurement errors due to a fixed delay operation within the control loop. The source of this error is mathematically analyzed in this paper. The modified DSC-PLL model overcomes the error by using a positive sequence αβ detector and a notch filter. The proposed method not only rejects the double frequency oscillation appearing at the output of the PLL under unbalanced loading conditions but also offers good harmonic rejection with nonlinear loads. The proposed model adds minimal complexity to the existing DSC-PLL. To ensure a fast dynamic response as well as a stable operation, a systematic approach is proposed to design the controller gains and filter parameters. The newly designed PLL is simulated and tested for performance verification purposes.


Electrical and Computer Engineering

Research Center/Lab(s)

Intelligent Systems Center


This work was supported by the Department of Engineering and Technology, Southeast Missouri State University.

Keywords and Phrases

Delay lock loops; Errors; Harmonic analysis; Locks (fasteners); Mathematical models; Notch filters; Oscillators (electronic); Delays; Frequency measurements; Micro grid; Signal cancellation; Synchronous reference frame; Phase locked loops; Delayed-signal-cancellation; Phase-locked loop; Synchronous reference frame PLL

International Standard Serial Number (ISSN)

0885-8969; 1558-0059

Document Type

Article - Journal

Document Version


File Type





© 2019 Institute of Electrical and Electronics Engineers (IEEE), All rights reserved.

Publication Date

01 Jun 2019