In this paper, an optimisation method utilising the yellow saddle goatfish algorithm (YSGA) with a new fitness function is proposed to design two types of fractional-variable-order PID (FVOPID) digital controllers for the automatic voltage regulator (AVR) system. Simulations and comparisons of the results are presented, showing that variable-order control can perform better than the existing solutions for the AVR system. Additionally, we include a stability analysis of a closed-loop system by utilisation of the Nyquist stability criterion.

中文翻译：

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用混沌黄鞍山羊鱼算法调整的分数变阶数字控制器设计用于 AVR 系统

在本文中，提出了一种利用具有新适应度函数的黄鞍山羊鱼算法（YSGA）的优化方法来设计自动电压调节器（AVR）系统的两种分数变阶PID（FVOPID）数字控制器。对结果进行了仿真和比较，表明变阶控制可以比 AVR 系统的现有解决方案执行得更好。此外，我们还利用 Nyquist 稳定性准则对闭环系统进行了稳定性分析。