Mahmoud R A, Malik O P, Fayek W M
Misr University for Science and Technology (MUST), College of Engineering Science & Technology, Department of Electrical Power and Machines Engineering (PME), 6th of October City, Giza, Egypt.
Electrical and Software Engineering Department, University of Calgary, Alberta, Canada.
Sci Rep. 2025 Aug 11;15(1):29309. doi: 10.1038/s41598-025-12475-9.
Precise evaluation of fault current model parameters is an important issue in protection and automation systems. These parameters play a crucial role in selecting protective relay settings, detecting, and compensating saturated CT waveforms, calculating AC and DC components, estimating the sub-transient and transient time periods for the short-circuit current, determining fault locations, and controlling a fault interruption to avoid very fast transients that arise from switching. A new strategy for calculating the fault parameters using short-circuit current model is presented. The short-circuit current data is used to estimate fault inception angle, decay time constant, power system angle and maximum symmetrical AC fault current. The difference concept can be utilized to obtain precise mathematical formulas for evaluating the parameters of the fault current model. This is for efficient implementation of multiple functions that include digital protective relay, fault locator, digital filter, CT saturation detector and compensator. The strategy can be applied offline or in real-time. To verify the developed methodology, comprehensive numerical studies on a power system with real parameters data are presented. The power system is simulated using the Alternative Transient Program (ATP) tool. The algorithm is processed using MATLAB© software application. It is examined under variable operating and fault conditions for the system. The quantitative findings indicate that the method has high feasibility, and can achieve reliability, accuracy, and speed in estimating fault current parameters. The results also demonstrate the effectiveness of the proposed algorithm, as well as its robustness with respect to changes in system parameters. Its performance is sustainable as the data window moves, and it is immune to different fault and operational conditions. A key highlight of the proposed approach is the ability to perform many tasks of computer applications in power systems using the accurate calculated parameters for the fault current model.
精确评估故障电流模型参数是保护与自动化系统中的一个重要问题。这些参数在选择保护继电器设置、检测和补偿饱和电流互感器（CT）波形、计算交流和直流分量、估算短路电流的次暂态和暂态时间段、确定故障位置以及控制故障中断以避免开关操作产生的极快速暂态方面起着至关重要的作用。本文提出了一种使用短路电流模型计算故障参数的新策略。短路电流数据用于估算故障起始角度、衰减时间常数、电力系统角度和最大对称交流故障电流。可以利用差值概念来获得用于评估故障电流模型参数的精确数学公式。这有助于高效实现包括数字保护继电器、故障定位器、数字滤波器、CT饱和检测器和补偿器在内的多种功能。该策略可离线或实时应用。为了验证所开发的方法，本文对具有实际参数数据的电力系统进行了全面的数值研究。使用交替瞬态程序（ATP）工具对电力系统进行仿真。算法使用MATLAB©软件应用程序进行处理。在系统的可变运行和故障条件下对其进行检验。定量结果表明该方法具有很高的可行性，并且在估算故障电流参数方面能够实现可靠性、准确性和速度。结果还证明了所提算法的有效性及其对系统参数变化的鲁棒性。随着数据窗口移动，其性能具有可持续性，并且不受不同故障和运行条件的影响。所提方法的一个关键亮点是能够使用故障电流模型的精确计算参数来执行电力系统中计算机应用的许多任务。
