Abrar Sk Fahim, Masood Nahid-Al, Alam Mohammad Jahangir
Department of Electrical and Electronic Engineering, Bangladesh University of Engineering and Technology, Dhaka, 1205, Bangladesh.
Heliyon. 2024 Nov 1;10(21):e40043. doi: 10.1016/j.heliyon.2024.e40043. eCollection 2024 Nov 15.
System stability issues regarding frequency and voltage in modern power systems are growing in importance as they incorporate more and more complex components. To ensure a sustainable, pollution-free power generation, modern power systems are designed to incorporate more renewable generation sources than traditional ones. Therefore, in the event of a large-scale disruption event, conventional load-shedding strategies are unable to keep the voltage and frequency limit below the threshold value. The suggested approach takes into account this issue by rating load buses in relation to relevant frequency changes, their voltage stability, system load damping coefficients, and the introduction of green energy sources in place of fossil fuel-based ones. Battery Energy Storage Systems (BESS) are used in the proposed method to minimize load shedding amount required for conventional schemes. After determining the amount, the scheme dynamically chooses feeders as per relative weightage of the stability components (voltage, frequency) to ensure that the overall load shed amount is near to the calculated value. To verify this, the scheme is tested on IEEE 39 bus with python scripted simulation. There are four scenarios considering 250 MW, 500 MW and 1500 MW injection of PV based power generation sources with conventional generation loss of 800 MW and 1000 MW. The threshold frequency is considered 49.10 Hz. The total amount of BESS is 300 MW. For every scenario, it has been found that the methodology successfully maintains the system frequency above 49.10 Hz with a minimal amount of load shedding. Hence, the proposed methodology is able to maintain frequency stability for a modern power system with large-scale PV generation through adaptive feeder selection for load shedding.
随着现代电力系统包含越来越多复杂的组件，与频率和电压相关的系统稳定性问题变得越来越重要。为了确保可持续、无污染的发电，现代电力系统设计中纳入的可再生能源发电来源比传统系统更多。因此，在发生大规模干扰事件时，传统的负荷削减策略无法将电压和频率限制保持在阈值以下。所建议的方法考虑到了这一问题，通过根据相关频率变化、负荷母线的电压稳定性、系统负荷阻尼系数以及用绿色能源替代化石燃料能源来对负荷母线进行评级。在所提出的方法中使用了电池储能系统（BESS），以尽量减少传统方案所需的负荷削减量。确定该量后，该方案根据稳定性组件（电压、频率）的相对权重动态选择馈线，以确保总的负荷削减量接近计算值。为了验证这一点，该方案在IEEE 39节点系统上使用Python脚本模拟进行了测试。有四种场景，分别考虑注入250兆瓦、500兆瓦和1500兆瓦基于光伏的发电来源，同时传统发电损失800兆瓦和1000兆瓦。阈值频率设定为49.10赫兹。BESS的总量为300兆瓦。对于每种场景，都发现该方法能够成功地将系统频率维持在49.10赫兹以上，且负荷削减量最小。因此，所提出的方法能够通过自适应选择馈线进行负荷削减，为具有大规模光伏发电的现代电力系统维持频率稳定性。
