加装感应电机阻尼器的组合式次同步谐振抑制方案

摘要

附加励磁阻尼控制器(SEDC)作为一种造价较低的电力系统次同步谐振(SSR)抑制装置,已经应用于多个电力系统的实际工程.但是研究和实验表明,当系统受到大的扰动时,SEDC可能无法彻底抑制SSR的发生.为了弥补SEDC在暂态故障时阻尼不足的缺点,提出了一种组合式SSR抑制方案.通过SEDC的反馈控制持续地提供阻尼,抑制稳态和小扰动时SSR的发生;在系统受到大扰动后,通过在发电机轴系一端加装感应电机阻尼器(IMDU)来抑制故障时的暂态力矩放大.基于IEEE次同步谐振第一标准测试系统的仿真分析表明,所提出的组合式次同步谐振抑制方案能较好地防范电力系统在稳态和暂态产生SSR的风险.%As a low-cost countermeasure for damping power system subsynchronous resonance (SSR), supplementary excitation damping controller (SEDC) has already been used by the industry. However, researches and field tests show SEDC does not provide enough damping to prevent torsional interactions which occur under large transient disturbances of the power systems. A new control scheme to solve the problem with a combination of an SEDC and an additional induction machine damping unit (IMDU) is proposed. By phase shifting and amplifying of the feedback control signal, the SEDC can provide effective damping for steady state and small disturbance operations. The IMDU is mechanically coupled to the generator shaft, acting like an active damping controller to mitigate the transient torque amplification during system transients. Time domain simulation results based on IEEE SSR first benchmark show the combined control scheme can eliminate SSR instabilities in both steady and transient states of power systems.