Abstract In solar thermal plants, as in any industrial process, it is important to maintain good control of the system and, more importantly, to have a good security system to avoid exceeding the safety limits of the components and avoid their degradation. In the case of solar thermal plants, one of the main components is the Heat Transfer Fluid (HTF), which must be kept below a maximum temperature. Although the temperature of the fluid, in general, will be controlled by modifying the flow-rate, when the plant is saturated HTF temperature is kept under limits by defocusing of the collectors. In this paper, an analysis of the control of the defocus control applied to the different collectors is presented. A Model Predictive Control technique will be applied to control the temperature by defocusing two and four collectors in different situations. It is shown how controlling the temperature by defocusing only two collectors is not sufficient in all situations and that controlling by defocusing the four collectors solves this problem in addition to maintaining the defocus actions in areas with high control authority.

中文翻译：

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抛物槽收集器散焦分析：两个控制级与四个控制级

摘要 在太阳能热电厂中，与任何工业过程一样，重要的是保持系统的良好控制，更重要的是拥有良好的安全系统，以避免超出组件的安全限制并避免其退化。对于太阳能热电厂，主要成分之一是传热流体 (HTF)，它必须保持在最高温度以下。虽然流体的温度通常会通过改变流速来控制，但当设备饱和时，HTF 温度会通过收集器的散焦保持在限制之下。在本文中，对应用于不同收集器的散焦控制的控制进行了分析。将应用模型预测控制技术通过在不同情况下散焦两个和四个收集器来控制温度。