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This paper investigates the use of a collection of dispatchable heating, ventilation and air conditioning (HVAC) loads to absorb the slow (low-frequency) fluctuations in solar photovoltaic (PV) generation. We first formulate the building's thermal dynamics and the associated optimization problem. An optimization formulation is then designed based on traditional model predictive control algorithm,...
Gas-liquid cylindrical cyclone separators are widely used in several applications, including bulk separation of hydrocarbons. Recently, these separators have been considered for subsea separation because of their low weight and compact design. However, disadvantages associated with their design are the resulting fast dynamics and small operational volume, which make them highly sensitive to flow variations...
In this paper a Model Predictive Control (MPC) strategy is utilized to model a professional driver negotiating a set driving circuit in minimum time. MPC is inherently suboptimal because not all future information is incorporated into each horizon of the control scheme. Motivated by how professional drivers learn race circuits in order to best exploit its features, we will alleviate some of the suboptimality...
Extremal problems for parabolic systems with time-varying lags are presented. An optimal boundary control problem for distributed parabolic systems with boundary conditions involving time-varying lags is solved. The time horizon is fixed. Making use of Dubovicki-Milutin scheme, necessary and sufficient conditions of optimality for the Neumann problem with the quadratic performance functionals and...
This paper presents a novel approach for timeoptimal model predictive control. In contrast to a global uniform time scaling, the underlying optimal control problem rests upon a dynamic, local temporal discretization of the shooting grid. The approach seeks for a grid partition with minimum overall transition time. Furthermore, a multi-stage optimization iteratively adapts the number of grid points...
A comparative analysis of the plug-in fuel cell vehicles (PFCV) is studied regarding different topologies, drive cycles and control strategies. To improve the performance of the PFCV, an optimization strategy is proposed at first by regulating the power distribution between the battery and the PEMFC system. Then, a direct multiple shooting (DMS) algorithm is used to solve this nonlinear programming...
For the solution of optimal control problem involving an index-1 differential-algebraic equation, an efficient function evaluation algorithm is proposed in this paper. In the evaluation procedure, the state equation is propagated forwards, then, adjoint sensitivity is propagated backwards. Thus, it is computationally more efficient than forward sensitivity propagation when the number of constraints...
In this article, after introducing fuzzy-dual numbers, functions and functionals, the optimization of a fuzy-dual functional is considered through an extension of Euler's condition. Then, once uncertainty is imbedded in a fuzzy-dual dynamical system, the optimization of such systems is considered, leading to an extended Hamilton-Jacobi-Bellman equation to characterize optimal fuzzy-dual solutions.
The new distributed propulsion configuration (DPC) can effectively improve aircraft fuel efficiency and reduce pollution, but also brings in cross-coupling effects between the aircraft aerodynamics and propulsion system. To tackle this problem, an integrated flight/propulsion optimal control is required, which is a constrained optimization problem without an explicit objective function, and most traditional...
The finite element orthogonal collocation method is widely used in discrete differential algebraic equations (DAE), while the discretization strategy significantly affects the accuracy and efficiency of dynamic problem solving. A finite element meshing method with error estimation on noncollocation point is proposed. Firstly, Radau collocation points based Lagrange interpolation polynomial are used...
In this paper, we consider an optimal control problem arising in a one-dimensional (1D) Magnetohydrodynamic (MHD) flow, which can be modelled by a coupled partial differential equations (PDEs) where the external control input (external induction of magnetic field) takes the multiplicative effect exerted on both state variables (momentum and magnetic components). The aim is to derive the flow velocity...
This paper proposes an experimental comparison between two optimal controllers for automotive spark ignition engines, including an gain-scheduled linear quadratic regulation (LQR) controller and model predictive controller (MPC). The aim of the study is to highlight the control effects between the LQR and MPC scheme on the specific engine control problem, and provide a reference for the future controller...
A difficulty still hindering the widespread application of Model Predictive Control (MPC) methodologies, remains the computational burden that is related to solving the associated Optimal Control (OC) problem for every control period. In contrast to numerous approximation techniques that pursue acceleration of the online optimization procedure, relatively few work has been devoted towards shifting...
The paper presents an optimal control strategy for a heavy-duty multi-group transmission that allows for simultaneous shifting in all groups. The approach is presented for a two-group transmission without loss of generality. The optimal control problem (OCP) consists of three phases with state-dependent switching of the hybrid dynamics and free end-time characteristics as well as several input and...
This paper considers an optimal harvesting strategy problem arising in shrimp culture. The problem is formulated as an optimal control problem of nonlinear impulsive system. Since the impulsive switching constraints is very complex, the impulsive switching instants are unknown, and the objective function is not continuously differentiable, it is difficult to solve this problem by standard optimization...
This work develops a lexicographic approach to multi-objective optimal control on models for cyber-physical systems, encompassing in particular stochasticity, limited access to model variables (partial observations), and possibly hybrid (continuous and discrete) dynamics (with the finite state POMDP framework as a known special instance). The technique is showcased in two new case studies in the area...
Control of the object with one output using many inputs is widely used for combining the advantages of every input and eliminating of disadvantages of two or more control channels. Such systems are called MISO, which means Many Inputs — Single Output. For the calculation of such systems we have proposed a theory based on the logarithmic frequency response. This method has proved to be excellent in...
The re-entry phase of the reusable launch vehicle (RLV) is a challenging optimal control problem because of its high nonlinearity and numerical sensitivity. In this paper, a recently proposed metaheuristic optimization algorithm, Sine-Cosine Algorithm(SCA) is employed to solve the re-entry trajectory problem for space shuttle vehicle. A cost function which maximizes the cross range along with satisfying...
Extremal problems for time lag parabolic systems are presented. An optimal boundary control problem for distributed parabolic systems in which constant time lags appear in the state equations and in the boundary conditions simultaneously is solved. Such equations constitute in a linear approximation a universal mathematical model for many processes of optimal heating. The time horizon is fixed. Making...
Power system stabilizers (PSSs) are generally used to damp low frequency oscillations. Usually, a classical PSS uses a fixed, second-order model, for which a mere tuning of its parameters is required. These controllers have been implemented successfully for many years. However, conventional PSSs may become inadequate when the operating conditions of the system are changing widely, because of the lack...
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