Research on Magnetic Field Calculation and Protective Area of Bridge Arm Reactors

Voltage Source Converter-based High Voltage Direct Current (VSC-HVDC) systems are widely used and the bridge arm reactor is a key component of the transmission converter station in these systems. Dry-type air-core structure bridge arm reactors have significant advantages but suffer from severe leakage flux, posing potential safety risks to maintenance personnel. Optimizing the reactor structure or designing magnetic field shielding structures using finite element algorithms is a commonly researched solution. However, these methods have longer development cycles and higher costs. Therefore, this paper establishes the single-phase two-dimensional axisymmetric and three-phase simplified three-dimensional simulation models of the bridge arm reactor. Considering the operational requirements for maintenance personnel, the magnetic field distribution around the reactor at a height of 1.8m above the ground is calculated by using the multi-physics field calculation software TR-Sim V2024. Based on relevant standards, two specific protection measures are proposed. By accurately setting the range of protection signs, the cost of the protection measures is reduced while ensuring the safety of maintenance personnel, providing valuable assistance for project implementation.