An Estimation of Hydraulic Power Take-off Unit Parameters for Wave Energy Converter Device Using Non-Evolutionary NLPQL and Evolutionary GA Approaches

Abstract

This study is concerned with the application of two major kinds of optimisation algorithms on the hydraulic power take-off (HPTO) model for the wave energy converters (WECs). In general, the HPTO unit’s performance depends on the configuration of its parameters such as hydraulic cylinder size, hydraulic accumulator capacity and pre-charge pressure and hydraulic motor displacement. Conventionally, the optimal parameters of the HPTO unit need to be manually estimated by repeating setting the parameters’ values during the simulation process. However, such an estimation method can easily be exposed to human error and would subsequently result in an inaccurate selection of HPTO parameters for WECs. Therefore, an effective approach of using the non-evolutionary Non-Linear Programming by Quadratic Lagrangian (NLPQL) and evolutionary Genetic Algorithm (GA) algorithms for determining the optimal HPTO parameters was explored in the present study. A simulation–optimisation of the HPTO model was performed in the MATLAB/Simulink environment. A complete WECs model was built using Simscape Fluids toolbox in MATLAB/Simulink. The actual specifications of hydraulic components from the manufacturer were used during the simulation study. The simulation results showed that the performance of optimal HPTO units optimised by NLPQL and GA approaches have significantly improved up to 96% and 97%, respectively, in regular wave conditions. The results also showed that both optimal HPTO units were capable of generating electricity up to 62% and 77%, respectively, of their rated capacity in irregular wave circumstances.

Green Energy Technology

“…Thus, this is an innovative method for effective treatment for toxic phenol contaminant elimination from aqueous solutions. Jusoh et al [14] applied two major kinds of optimization algorithms (Quadratic Lagrangian (NLPQL) and evolutionary Genetic Algorithm (GA)) on the hydraulic power take-off (HPTO) model for the wave energy converters (WECs). The optimal simulation results showed that the performance of HPTO units has significantly improved up to 96% and 97%, respectively, in regular wave conditions.…”

“…This Special Issue of Energies on the subject of "Green Energy Technology" contains the successful invited submissions [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17]. A total of 17 technical papers that cover diversified green energy technology-related research have shown critical results and contributed significant findings in biofuel production [1], energy-saving in buildings [2], wind energy [3], energy policy [4], electricity supply [5], a thermal-hydraulic system [6], fluidized bed reactor [7], green-supply chains [8], SI engine [9], renewable energy grid [10], kinetic energy harvest [11], green hydrogen utilization [12], water conservation [13], hydraulic power [14], Illumination Performance in buildings [15], community renewable energy [16], and heat transfer [17].…”

Design Optimization of Electrodynamic Structure of Permanent Magnet Piston Mechanical Electric Engine

“…To find the optimal global solution of the optimization objective, the nonlinear sequential quadratic programming (NLPQL) algorithm is used to iteratively find the optimal combination of parameters that can maximize the engine output power. The algorithm applies a quadratic Taylor series to expand the objective function and linearize the constraints, transforming the original nonlinear problem into a quadratic programming problem [43,44].…”

Investigations of Hydraulic Power Take-Off Unit Parameters Effects on the Performance of the WAB-WECs in the Different Irregular Sea States

“…The WEC concept based on [20] is considered in the present study. The simplified concept is shown in Figure 1A.…”

“…Recently, several kinds of research into the HPTO in WAB-WECs have been published for various objectives, for example in [15][16][17][18][19][20][21]. From the literature, most of the studies have concentrated on the performance of the HPTO unit without investigating the influence of the important parameters of HPTO.…”