【摘要】 利用电磁暂态程序对电容式电压互感器 (CVT)的特性进行了数字仿真 ,发现CVT的暂态特性会造成距离保护的暂态超越和反方向出口误动作 .暂态超越现象与两侧电势相角差、故障时刻的电压初始相位密切相关 ,CVT暂态特性引起的反方向出口误动作仅仅发生在受电侧 ,且与两侧电势相角差有关 .分析结果表明 ,采用距离保护快速Ⅰ段的反时限特性是防止暂态超越的有效措施 ,同时提出了利用故障分量方向元件结合全阻抗特性继电器的方法 ,解决了距离保护反方向出口误动作问题 .更多还原

【Abstract】 CVT’s characteristics is simulated by electromagnetic transient program (EMTP), and it shows that distance relays is probably accompanied with a transient overreach or an antidirection maloperate for the sake of CVT’s transient response characteristics. The transient overreach has relation to the angular difference of both power supplies and the initiative voltage phase. The antidirection maloperating caused by the distance relay must be in receiving caused by the areas, and the angular difference has an effect on the maloperate of the relay too. The effective way to prevent distance relays from transient overreaching is to adopt the relay with adaptive speedreach characteristics. And a new method is proposed to make the distance relays work normally when the fault occurs near the device at antidirection by using directional relays based on fault components and full impendence relays.更多还原