Research on fault diagnosis for MMC-HVDC Systems

Abstract

Introduction: With the development of flexible HVDC technology, the fault diagnosis of MMC-HVDC becomes a new research direction. Based on the fault diagnosis theory, this paper proposes a robust fault diagnosis method to study the fault diagnosis problem of MMC-HVDC systems. Methods: By optimizing the gain matrix in the fault observer, fault detection with good sensitivity and robustness to disturbance is achieved. In the MMC-HVDC system, because of the inherently uncertain system and the presence of various random disturbances, the study of robust fault diagnosis method is particularly important. Results: Simulation studies during various AC faults have been carried out based on a 61-level MMC-HVDC mathematical model. The results validate the feasibility and effectiveness of the proposed fault diagnosis method. Conclusions: So this fault diagnosis method can be further applied to the actual project, to quickly achieve system fault diagnosis and accurately complete fault identification.

A Monopolar Symmetrical Hybrid Cascaded DC/DC Converter for HVDC Interconnections

“…S a milestone achievement in power electronics, modular multilevel converter (MMC) has significantly facilitated voltage source converter (VSC) based high voltage direct current (HVDC) transmission technology [1]- [3]. In the last decade, dozens of MMC-HVDC projects with different voltage ratings have been constructed worldwide.…”

Damping Torque Analysis of VSC-HVDC Supplementary Damping Controller for Small-Signal Stability

“…Research and design of VSC supplementary damping controller have been extensively investigated in recent years. VSC supplementary damping controller can enhance the decoupled power control of VSC stations so as to improve system dynamics [9,10]. In [11], a centralized multiple input multiple output (MIMO) supplementary controller is devised based on linear matrix inequality (LMI) based on regional pole configuration and homotopy transformation.…”

Power shift‐based optimal corrective control for bipolar multi‐terminal high‐voltage direct current grid

“…In recent years, as a promising VSC topology, the modular multi-level converter (MMC)-based MTDC grid offers an attractive solution to cope with the increased renewable energy source (RES) integration [11][12][13]. The MTDC grid with bipolar configuration takes the middle point between the positive and negative poles as the neutral bus, to which the ground electrode or dedicated metallic return is connected [14].…”