A Half-Tangent Phase-Locked Loop for Variable-Frequency Grids of the More Electric Aircraft

Integral‐type half‐tangent phase‐locked loop for more electric aircraft grids

“…Unfortunately, the above estimation strategies have complex structures, and their implementation is also tedious. In [26], a half-tangent PLL (HTan-PLL) is proposed for the varying-frequency AC grids of MEA. Similar with the SRF-PLL, the HTan-PLL has a simple structure and good steady-state accuracy, and it is easy to implement in practical engineering.…”

“…Similar with the SRF-PLL, the HTan-PLL has a simple structure and good steady-state accuracy, and it is easy to implement in practical engineering. It is shown in [26] that under any large frequency jumps, the HTan-PLL can converge to the stable point (0,0) directly, and no oscillations emerge. However, the influence of the harmonic disturbances is not considered in [26].…”

“…It is shown in [26] that under any large frequency jumps, the HTan-PLL can converge to the stable point (0,0) directly, and no oscillations emerge. However, the influence of the harmonic disturbances is not considered in [26].…”

“…According to Figure 4, it is known that under any large frequency jumps, the HTan-PLL converges to the stable point (0,0), and no oscillations emerge. However, the influence of the harmonic disturbances is not considered in Reference [26]. When the varying-frequency grids contain harmonic disturbances, the simulation results imply that the HTan-PLL still has oscillations in estimating frequency under large frequency jumps.…”

“…To address the disadvantages of the SRF‐PLL, the HTan‐PLL is developed in Reference [26]. The schematic diagram of the HTan‐PLL is shown in Figure 3, and its large‐signal model is expressed as $$$$\begin{equation} \def\eqcellsep{&}\begin{array}{l} \dot{\tilde{\theta }} = \tilde{\omega }\\[3pt] \dot{\tilde{\omega }} = - \dfrac{{{k}_p\tilde{\omega }}}{{2{{\cos }}^2({{\tilde{\theta }} \mathord{\left/ {\vphantom {{\tilde{\theta }} 2}} \right.$$…”