Novel adaptive reclosing scheme of MMC‐HVDC transmission lines based on phase synchronization compensation control

Abstract

Modular multilevel converter based on high voltage director current is important for large‐scale power regional interconnection. Adaptive reclosing is critical to improving the safety and economy of power transmission. The time‐frequency characteristics during fault clearance are analysed by Hilbert transform to suppress over‐voltage or over‐current resulting from short‐circuit fault. A phase synchronization compensation control algorithm is designed based on voltage and current through the virtual network. The rapid suppression of fault overvoltage is achieved by synchronously switching network attributes. Furthermore, the line recovery voltage is introduced into the fault property identification. The proposed adaptive reclosing scheme with high‐speed dynamics can raise the comprehensive benefits of the power system. Studies have verified that phase synchronization compensation control can effectively reduce the impact of oscillation. Moreover, permanent and transient faults can be quickly and reliably discriminated during de‐ionization by multi‐device coordination, which is earlier than the traditional adaptive reclosing scheme. It provides a basis for the fault recovery optimization strategy coordinating with multiple equipment.

Presynchronization control for ship microgrid of merchant marine inverters based on VSG algorithm with MFAC

“…As a type of GFM converter control, the virtual synchronous generator (VSG) algorithm provides artificial inertia to the microgrid and regulates the frequency of voltage, and supplies uninterruptible power (UPS) between different operational modes for distributed generation inverters (Kumaravel et al, 2019). Thence, a stable presynchronization control with VSG algorithm is the key to ensure the smooth transition of distributed generation inverters of the large merchant marine between the grid-connected mode and the islanded mode (Zhang et al, 2022).…”