电路容差对继电保护装置可靠性影响的分析方法

Method to Analyze Effect of Circuit Tolerance on Reliability of Protective Relays

为了分析电路容差对继电保护装置可靠性的影响,提出以正确响应率作为可靠性指标,以系统实际输出信号幅值是否超出标称输出信号幅值的容差范围作为系统失效的可靠性判据,并确定了可靠性指标的置信区间估计.将OrCAD/PSpice软件的电路仿真功能与蒙特卡罗法相结合,基于点估计法和区间估计法求取可靠性指标及其置信区间.最后以数字保护装置的数据采样系统为算例,对其电路参数进行灵敏度分析,证实了所提出方法的正确性.

In order to analyze the effect of circuit tolerance on the reliability of protective relays, the correct response rate is presented as the reliability index, and the corresponding confidence interval is estimated. Moreover, a reliability criterion is proposed, that is, the system fails when the practical magnitude of system output signal exceeds the tolerance range of the nominal magnitude. By combining the circuit simulation function of OrCAD/PSpice software and Monte Carlo simulation method, the reliability index and its confidence interval can be obtained via point and interval estimations. As an example, the sensitivity of the component parameters in the data acquisition system of digital protector is analyzed, the results verifying the proposed method.