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The chiller system in a building accounts for the main part of the building's total energy consumption, so it is critical to optimize the operation of chiller system for the purpose of saving energy. A chiller system generally consists of evaporation side and condensing side. The condensing side includes chillers, cooling water pumps and cooling towers, which form a subsystem of cooling water. It...
Since its beginning around 50 years ago [1], the research on biped robotics developed many successful prototypes, however the conventional strategies of gait generation and control have diverse performance issues. Between the promising alternatives of strategies is Optimal Control, which offers a clear definition of performance criteria and precise methods for achieving it. To highligh the possibilities...
In order to achieve better energy saving effect of the super-capacitor energy storage system (SC-ESS), an on-line optimization control strategy is proposed in this paper. Firstly, the model of urban rail traction power supply system with super-capacitor energy storage system is established, and the working principle of ESS is analyzed. Then the paper analyzes the influence of train braking characteristics...
A novel control strategy for battery energy storage system (BESS) which is integrated within photovoltaic power station is presented in this paper. Normally the function of BESS is to mitigate the power fluctuation of PV to meet the requirements of dispatch center. In this paper, besides PV fluctuation smoothing, peak power shaving is also considered in the control strategy of BESS, which means part...
The train brake system is a complex pneumatic device whose performance and reliability are relatively important. When the train is beging braked, the coupler force caused by the inherent delays in pneumatic airbrakes, commonly used in freight trains, becomes relatively large. The problem is even severe for long freight trains where the delayed response involves heavy longitudinal forces between vehicles...
Two novel hybridization schemes for the particle swarm repetitive controller (PSRC) are developed and tested herein. They are designed to be used in power electronic converters, such as grid-tie converters or constant-amplitude constant-frequency (CACF) true sine wave inverters, as well as in motion control systems, especially in assembly line robots. The proposed control algorithms combine the good...
In the past few years, the interest in model predictive control (MPC) for power electronics has increased significantly. It proves to be a good alternative to space-vector modulation at low switching frequencies. It has been shown that an increase in the prediction horizon improves the system performance. Unfortunately, increasing the horizon leads to an exponential increase in the complexity of the...
In this paper, optimization problem of after treatment system is investigated for diesel engines with lean NOx trap (LNT). First, a control-oriented LNT model is developed based on energy and mass balancing rules. Then, the optimization problem is formulated as a dynamic programming (DP) problem under developed dynamical model constraint and a trade-off between fuel economy and NOx emission is considered...
This paper deals with model predictive control of a separated flow around a 2D circular cylinder at a low Reynolds number. The magnitude of the radial velocity on a small region of the cylinder surface is regarded as the control input. We set the objective function including a viscous dissipation function for each optimization step. In numerical simulations, flow separation and vortex shedding are...
This paper proposes a method to solve nonlinear finite-horizon optimal control problems of discrete-time polynomial systems with polynomial terminal constraints. Algebraic equations with all variables at each time step, which are independent of variables at other time steps, are derived from the necessary conditions for optimality by eliminating variables recursively. The candidates of the optimal...
In this paper, constrained non-stationary state feedback speed controller for PMSM drive fed by VSI with SiC MOSFETs is presented and experimentally verified. The novelty of proposed approach lies in direct design of non-stationary state feedback controller for non-linear and cross-coupled model of the plant. An artificial bee colony (ABC) optimization algorithm is applied to automatic selection of...
This study develops discrete mechanics for 1-dimensional distributed parameter mechanical systems under free boundary conditions, and a control method for the systems based on a blending method of discrete mechanics and nonlinear optimization. First, under the assumption on free boundary conditions, discrete Euler-Lagrange equations and boundary equations are derived by discrete Hamilton's principle...
This paper proposes a control strategy for the dual-BESS system using optimal control. Previously designed one-step MPC (Model Predictive Control) based strategy is extended for a dual-BESS case. To this end, a two-stage optimal control problem is solved. Since the resulting algorithm for charging and discharging of dual BESS comes in the form of a simple if-then statement, it is easy to implement...
A method for evaluating driving technique and engine operation, with emissions constraints, on a real driving route, is presented. A single degree of freedom vehicle model with simple resistive forces is driven along the pre-planned route. Instead of the velocity trajectory being determined a priori, the optimisation can choose the optimal speed along the route as well as the engine operating point...
In this study a powerful optimization algorithm is used for optimal tuning of linear quadratic regulator (LQR) based PSS in order to stabilize a synchronous machine which is connected to an infinite bus. Jaya algorithm is a newly proposed AI optimization algorithm inspired from TLBO. The robustness of optimized controller by the Jaya algorithm has been compared regarding to commonly used types of...
Hands-off control (or sparse control) is a control that has a small support length that achieves a given control objective. In other words, hands-off control takes zero on a relatively long time duration. Recently, this idea is extended to distributed control for consensus, called distributed hands-off control. In this control, each agent uses hands-off control, which is a bang-off-bang control taking...
This work provides a comparative review of three different numerical methods generally used to discretize continuous-time non-linear equations appearing in model predictive control problems: direct multiple shooting, direct collocation and successive linearizations. An overview of the characteristics of each method is given and the performance of each method is evaluated through the simulation of...
This research presents a predictive engine that integrates into an on-line optimal control planner for electrical microgrids. This controller models the behavior of the underlying system over a specified time horizon and then solves for a control over this period. In an electrical microgrid, such predictions are challenging to obtain in the presence of errors in the sensor information. The likelihood...
In the present paper we investigate a novel approach for optimal control based testing of flight control laws with respect to worst case pilot inputs, disturbances, such as wind gusts, and worst case parameter combinations. For the latter we consider parameters with fixed bounds, such as aircraft mass and statistically distributed parameters for the aerodynamic data set. In order to determine appropriate...
This paper presents the implementation and experimental validation of a central control framework. The presented framework addresses the need for a controller, which provides high performance combined with a low-computational load while being on-line adaptable to changes in the control scenario. Examples for such scenarios are cooperative control, task-based control and fault-tolerant control, where...
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