Abstract This article addresses the problem of controlling the growth of microalgae originating in Mexican rivers, especially in the state of Sinaloa, Culiacan River. For this purpose, a robust, high-gain nonlinear observer is proposed to estimate the unknown disturbance in the cultivation of mixotrophic microalgae with the presence of organic nutrients. Once a perturbation function related to the change of ambient light is estimated, an output feedback control for the photobioreactor is proposed, in which through Lyapunov’s convergence functions, the final boundary stability conditions are obtained. Thus, a turbidity sensor was designed for Spirulina platensis, a native microalgae of Culiacan River, which is presented using the MATLAB-Arduino programming environment. This sensor is calibrated using biomass culture and is a low-cost device. Through the numerical study, the feasibility and performance of the control and the observer are evaluated. Finally, real-time experimental evaluations are made based on the literature, studying the use of robust controllers in a photobioreactor with a mixed culture, in the presence of environmental changes in lighting.

中文翻译：

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基于 NL-PI 观测器的浊度传感器开发：在锡那罗亚河最大螺旋藻栽培控制中的实验应用

摘要 本文解决了控制源自墨西哥河流，特别是锡那罗亚州库利亚坎河的微藻生长的问题。为此，提出了一种鲁棒的、高增益的非线性观测器来估计存在有机营养物的混合营养微藻培养过程中的未知干扰。一旦估计了与环境光变化相关的扰动函数，就提出了光生物反应器的输出反馈控制，其中通过李雅普诺夫收敛函数，获得最终的边界稳定性条件。因此，我们设计了一种浊度传感器，用于库利亚坎河的原生微藻——钝顶螺旋藻，并使用 MATLAB-Arduino 编程环境呈现。该传感器使用生物质培养进行校准，是一种低成本设备。通过数值研究，评估了控制和观测器的可行性和性能。最后，基于文献进行实时实验评估，研究在光照环境发生变化的情况下，在混合培养的光生物反应器中使用稳健控制器。