具有环内变增益控制的自适应相位合成器以实现可靠的电网集成

Modern electrical distribution networks face challenges from dc offsets and harmonics within the grid voltage, often caused by nonlinear loads or power electronics devices. This article proposes a phase-locked loop (PLL) as an adaptive phase synthesizer with in-loop variable gain control (VGC) to achieve reliable grid integration. The design of this PLL builds upon a type-3 in-loop filter-based second-order generalized integrator (ISOGI), known for effective dc offset and harmonics filtering. To optimize transient performance, the ISOGI-VGC structure is introduced. The VGC controller provides dynamic bandwidth adjustment, enhancing both transient and steady-state response. Comparative simulations demonstrate the superiority of the proposed PLL design under various grid disturbances. Further validation is provided through a hardware prototype tested on a dSPACE real-time platform. The results confirm that the ISOGI-VGC-based type-3 PLL delivers improved performance and reliable grid integration.