基于暂态主频实时估算的快速距离保护

为提高继电保护的动作性能,针对故障时高频噪声分量中暂态主频分量占主导的特点,提出一种实时估算暂态主频的方法,并应用于主频模型的最小二乘算法；根据算法模型中预设暂态主频与实际暂态主频的正负误差导致算法误差大致呈现符号相反的特性,提出一种新的自适应距离保护方案,该方案采用对多组暂态主频模型算法结果相与构成保护输出.仿真结果表明,该方案能够有效地降低区外故障超越程度,提高距离保护范围,同时能够在区内故障时提高保护动作速度.

Fast distance protection based on real-time estimation of transient main frequency

The component of transient main frequency plays a leading role in the high frequency noises during the fault. To improve operating performance of relay protection, a real-time estimation method of transient main frequency was put forward, and applied to the least square algorithm with model of main frequency. The phenomenon was obtained that the positive and negative error between true transient main frequency and the presetting one in the algorithm model cause the algorithm error sign approximately inverse. A new adaptive distance protection scheme was proposed by making results of several transient main frequency model algorithms composing AND gate as the protection output. Simulation results indicate that this scheme can effectively minish overreach range for external faults and increace the reach of distance protection. Furthermore,it can quicken the operating speed of protection for internal faults.