Adaptive repetitive control for resonance cancellation of a distributed solar collector field

Abstract

This paper deals with modelling and control of the outlet temperature in a distributed solar collector field. The resonance dynamics characteristics of this kind of system are similar to those of tubular heat exchangers in the closed-loop system bandwidth when fast responses are required. Simple low-order rational models are unable to capture the resonance dynamics, which can be excited by changes in both the heat transfer fluid flow and solar irradiation.This paper proposes a new model derived from a similar model for a tubular heat exchanger. This model allows the use of low-order controllers, which can be extended to an adaptive control scheme to account for varying resonance frequencies, as a new functionality achieving fast, well-damped responses.

A feedback control system with reference governor for a solar membrane distillation pilot facility

“…Notice that the thermal mass capacity of the solar field material has not been finally considered in Eq. 1 as its effect in the obtained mean quadratic error is almost negligible, while introducing an additional differential equation following the approach in [26]. So, the model in Eq.…”

Moving-Horizon Modulating Functions-Based Algorithm for Online Source Estimation in a First-Order Hyperbolic Partial Differential Equation

“…These factors motivate the soft-sensing of the efficient value of the energy source term resorting to an online estimation algorithm. The estimated value of the source term is then injected in an indirect adaptive controller, considering the tremendous number of studies on control of the solar collector strategies [3][4][5].…”

“…Proposition 1. Let ∑ J j=1 γ j ξ j (t) be a basis expansion of the unknown source S(t) in (5), where t ∈ w k = [t l k ,t u k ]; ξ j (t) and γ j , for j = 1, • • • , J, are basis functions and basis coefficients, respectively. Let {φ m (t)} m=M m=1 be a class of on-line modulating functions that satisfy (10) with l ≥ 1 and M ≥ J.…”

Towards an improved gain scheduling predictive control strategy for a solar thermal power plant

“…It is claimed that taking explicit account of the field inlet–outlet temperature time delay improves the feedforward capabilities in terms of compensating for changes in the field inlet temperature. In [8] and after performing some simplifications and Taylor series expansions to a non‐linear distributed parameter model of the plant, transfer functions relating the dynamics of solar radiation and the field inlet temperature to the field outlet temperature are obtained. The transfer functions are used for the design of a classical parallel feedforward compensation.…”