The union of different devices in order to obtain a specific response for a process is commonly called a control system. For a control system, it is necessary to have one or more controllers. Among the most used in the industrial sector are the PID and PI controllers. Next to these controllers is the control software. Scilab is a good example of control software. It is characterized as free code software, with no cost for its acquisition, in addition to having a large computational power and integrated tools, such as Xcos, intended for modeling and simulation. For the union with Scilab, there is Arduino. Such a mixture can be used, for example, to control liquid levels in tanks. In this context, the present work aims to study the tank-level control system based on PID and PI controllers through the union between Scilab and Arduino. Phenomenological models were developed based on closed-loop control (feedback control system) of the process with two tanks not coupled with recycle. Furthermore, for comparison purposes, two approaches were used for each process: one considering the saturation of the manipulated variable and the other without the presence of such saturation. At first, there was a need to implement an anti-windup system. For tuning the controller parameters, the ISE method was used, executed through a programming code developed in Scilab. The parameters found for the two systems were tested on a made-up experimental bench. Therefore, using the block diagrams and the method here called “ISE method”, satisfactory values were obtained for the control parameters. These were ratified in the tests carried out in the experimental module. Level control was achieved with greater prominence for the PI controller since there is one less parameter to be tuned and processed by the system. This controller provided results close to the PID controller for cycles up to 50%. In general, the PI controller showed maximum response deviations smaller than the PID, such as deviations of 1.55 cm and 2.40 cm, respectively, for the case with 75% recycle. It was also clear the influence of the saturation of the manipulated variable on the system response, but not on the tuning of the controller parameters.

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回收对过程控制的影响分析

为了获得过程的特定响应而结合的不同设备通常称为控制系统。对于一个控制系统来说，必须有一个或多个控制器。工业领域最常用的是 PID 和 PI 控制器。这些控制器旁边是控制软件。Scilab 是控制软件的一个很好的例子。它的特点是免费代码软件，无需购买成本，此外还具有强大的计算能力和集成工具，例如用于建模和仿真的 Xcos。对于与 Scilab 的联合，有 Arduino。例如，这种混合物可用于控制罐中的液位。在此背景下，本工作旨在通过Scilab和Arduino的结合，研究基于PID和PI控制器的罐位控制系统。唯象模型是基于两个不与循环耦合的罐的过程的闭环控制（反馈控制系统）而开发的。此外，出于比较的目的，每个过程使用了两种方法：一种考虑操纵变量的饱和度，另一种不考虑操纵变量的饱和度。起初，需要实施防清盘制度。为了调整控制器参数，使用了 ISE 方法，通过 Scilab 开发的编程代码执行。两个系统的参数在一个搭建的实验台上进行了测试。因此，使用框图和此处称为“ISE 方法”的方法，获得了令人满意的控制参数值。这些在实验模块中进行的测试中得到了批准。由于系统需要调整和处理的参数少了一个，因此 PI 控制器更加突出地实现了液位控制。对于高达 50% 的循环，该控制器提供的结果接近 PID 控制器。一般来说，PI 控制器表现出比 PID 更小的最大响应偏差，例如对于 75% 回收率的情况，偏差分别为 1.55 cm 和 2.40 cm。还可以清楚地看到操纵变量的饱和对系统响应的影响，但对控制器参数的调整没有影响。例如，对于 75% 回收率的情况，偏差分别为 1.55 厘米和 2.40 厘米。还可以清楚地看到操纵变量的饱和对系统响应的影响，但对控制器参数的调整没有影响。例如，对于 75% 回收率的情况，偏差分别为 1.55 厘米和 2.40 厘米。还可以清楚地看到操纵变量的饱和对系统响应的影响，但对控制器参数的调整没有影响。