基于“电压补偿”的地铁直流联跳保护误动作解决方法

摘要

牵引变电所的联跳保护是直流侧重要的保护之一，对于保障供电设备和人身安全具有重要作用。但在直流系统保护运行中，会出现联跳保护误动作的情况，造成相邻变电所跳闸，在大范围内中断供电。为了从根本上解决联跳保护误动作的问题，以南京地铁一号线为例，研究分析联跳保护误动作的原因和机理，提出采用“电压补偿”的方法对保护回路的继电器元件优化设计，使保护回路的接触电阻值减小。经施工改造后运行实况证明该方法简捷可靠，成本低廉，有效解决了联跳回路保护误动的问题。%substation bilateral tripping protection is one of the important protection of DC traction, which plays an important role in the security of power supply equipment and personal safety. But in the DC system protection operation, there will be joint protection misoperation, resulting in the neighboring substation tripping and interruption of power supply in large range. In order to fundamentally solve the problem of debugging the misoperation of protection, taking Nanjing Metro as an example, this paper analyzes the reason and mechanism of joint protection misoperation, proposes the "method of voltage compensation" to optimize relay element design of protection circuit and decrease the contact resistance value of protection circuit. The running after construction and transformation proves that the method is simple and reliable and has low cost, which effectively solves the tripping of misoperation of protection loop.