Overvoltage Suppression Strategy for HPFC Based on Bandwidth Adaptive LADRC and Improved Reactive Power Control

ABSTRACT Hybrid power flow controllers (HPFCs), with their inherent precise, continuous power flow regulation capability, have significant application prospects in renewable energy systems. However, partial fault conditions may induce transient overvoltages, compromising equipment integrity. Thus, a comprehensive overvoltage suppression strategy is proposed by integrating bandwidth‐adaptive linear active disturbance rejection control (LADRC) with reactive power coordination. Initially, the HPFC structural principles are analysed to characterise the internal power distribution and overvoltage mechanisms. An adaptive reactive power control scheme is developed by formulating the reactive power–voltage coupling dynamics within the hybrid controller. To address transient overvoltages during suppression initiation, an enhanced LADRC framework with controller bandwidth‐parameter‐adaptive tuning is introduced. This approach optimises the correlation between the critical bandwidth parameters and system response characteristics, enabling full‐cycle overvoltage mitigation. The strategy is validated using a hardware‐in‐the‐loop experimental platform consisting of RT‐LAB real‐time simulators and physical controllers. Compared with conventional PI control, a 15% reduction in the transient peak value of overvoltage was achieved by the proposed strategy, demonstrating the proposed method's efficacy and superiority in overvoltage suppression.