Готові списки джерел за темами / Hydraulic Power Take-Off

Добірка наукової літератури з теми "Hydraulic Power Take-Off"

Автор: Grafiati

Опубліковано: 14 березня 2023

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Статті в журналах з теми "Hydraulic Power Take-Off"

IMAI, Yasutaka, Shuichi NAGATA, Tengen Murakami, Ryotarou INOUE, and Yuki KODAMA. "English Hydraulic power-Take-Off." Proceedings of Conference of Kyushu Branch 2018.71 (2018): A21. http://dx.doi.org/10.1299/jsmekyushu.2018.71.a21.

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Huang, Qitao, Peng Wang, Yudong Liu, and Bowen Li. "Modeling and Simulation of Hydraulic Power Take-Off Based on AQWA." Energies 15, no. 11 (May 26, 2022): 3918. http://dx.doi.org/10.3390/en15113918.

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The AQWA software is often used to perform hydrodynamic analysis, and it is highly convenient for performing frequency domain simulations of Pelamis-like wave energy converters. However, hydraulic power take-off (PTO) must be simplified to a linear damping model or a Coulomb torque model when performing a time domain simulation. Although these simulation methods can reduce the computational complexity, they may not accurately reflect the energy capture characteristics of the hydraulic PTO. By analyzing system factors such as the flow and pressure of each branch of the hydraulic PTO, the output torque of the hydraulic cylinder to the buoy, and the electromagnetic torque of the generator, a relatively complete hydraulic PTO model is obtained, and the model is applied to AQWA using the FORTRAN language. Comparing and analyzing the simulation results of the linear damping model, the Coulomb torque model, and the hydraulic PTO, we found that the simulation results obtained by the linear damping model are quite different from those of the hydraulic PTO, while the torque characteristics, kinematic characteristics and energy capture characteristics of the Coulomb torque model are closer to those of the hydraulic PTO model. Therefore, it is more appropriate to simplify hydraulic PTO to a Coulomb torque model based on AQWA.

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Velichkova, R., M. Pushkarov, R. A. Angelova, I. Simova, D. Markov, I. Denev, and P. Stankov. "Hydraulic power take off system for wave energy utilization." IOP Conference Series: Materials Science and Engineering 1032 (January 21, 2021): 012030. http://dx.doi.org/10.1088/1757-899x/1032/1/012030.

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Zhang, Dahai, Wei Li, You Ying, Haitao Zhao, Yonggang Lin, and Jingwei Bao. "Wave energy converter of inverse pendulum with double action power take off." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 227, no. 11 (January 31, 2013): 2416–27. http://dx.doi.org/10.1177/0954406213475760.

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This article describes a double action hydraulic power take off for a wave energy converter of inverse pendulum. The power take off converts slow irregular reciprocating wave motions to relatively smooth, fast rotation of an electrical generator. The design of the double action power take off and its control are critical to the magnitude and the continuity of the generated power. The interaction between the power take off behavior and the wave energy converter’s hydrodynamic characteristics is complex, therefore a time domain simulation study is presented in which both parts are included. The power take off is modeled using AMESim®, and the hydrodynamic equations are implemented in MATLAB®; simulation is used to predict the behavior of the complete system. The simulation results show that the design of the double action hydraulic power take off for wave energy converter of inverse pendulum is entirely feasibility and its superiority has been verified by the preliminary experiments, especially compared with the existing single action power take off system.

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Xu, Jianan, Yansong Yang, Yantao Hu, Tao Xu, and Yong Zhan. "MPPT Control of Hydraulic Power Take-Off for Wave Energy Converter on Artificial Breakwater." Journal of Marine Science and Engineering 8, no. 5 (April 26, 2020): 304. http://dx.doi.org/10.3390/jmse8050304.

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Wave energy is a renewable energy source that is green, clean and has huge reserves. In order to develop wave energy resources, an oscillating buoy Wave Energy Converter (WEC) device based on the artificial breakwater is presented in this paper. In order to effectively vent the gas in the hydraulic PTO and to improve the active control capability of the PTO system to guarantee the safety performance of the system under high sea conditions, a hydraulic PTO with an active control circuit is designed. Additionally, for the Power Take-Off (PTO) system, there is a optimal damping point under different sea conditions for PTO system, so the PTO can be controlled by the Maximum-Power-Point-Tracking (MPPT) control algorithms to improve the generated power of the system. At present, the MPPT control algorithms for wave energy are mainly used to control the load of generator. However, a fixed-load storage battery is used for the load of the generator in this paper. Additionally, an MPPT control taken at a hydraulic PTO system is executed to improve the power generated by hydraulic PTO under different sea conditions effectively in this paper. The MPPT control based on the hydraulic system is conducted by controlling the displacement of hydraulic motor to achieve the optimal damping point tracking control. The control flow of the MPPT algorithm is provided. The variable step hill-climbing method is used in MPPT control algorithm in which the big step can reduce the time of tracking and the small step can increase the accuracy of MPPT control algorithm. Due to the slow stability of the hydraulic system, a filter method for hydraulic PTO power is used. In addition, the hydraulic PTO system and MPPT control are verified to be feasible with the simulation. Additionally, MPPT control based on hydraulic variable motor is easier to carry out in practical applications than the traditional control of resistance. Finally, the simulation results demonstrate that it is an effective power control strategy for hydraulic PTO system to improve the generated power.

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Niu, Yubo, Xingyuan Gu, Xuhui Yue, Yang Zheng, Peijie He, and Qijuan Chen. "Research on Thermodynamic Characteristics of Hydraulic Power Take-Off System in Wave Energy Converter." Energies 15, no. 4 (February 14, 2022): 1373. http://dx.doi.org/10.3390/en15041373.

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Hydraulic power-take-off (PTO) systems which utilize high-pressure oil circuits to transmit energy are widely applied in wave energy generation. The properties of hydraulic oil are significantly influenced by environmental conditions, and its dynamic viscosity is sensitive to temperature, especially in relatively low-temperature cases. This paper studies the characteristics of the hydraulic PTO when started in different temperature conditions via numerical analysis and experimental verification. An improved numerical model of the hydraulic PTO system is proposed, in which the effects of temperature on the hydraulic oil viscosity and hydraulic motor efficiency are quantitatively investigated, and consequently, the thermal-hydraulic characteristics can be sufficiently considered. The performances of the hydraulic PTO in start-up processes with different initial temperatures and in long term operation are assessed. The results show that the presented model can reasonably describe the hydraulic PTO characteristics. The efficiency of hydraulic PTO degrades when it starts at low temperatures. The efficiency increases in relatively high temperature, while larger fluctuations of the flow rate and output power are observed. This study can provide guidance for enhancing the efficiency and consistency of hydraulic PTO operating in actual sea conditions.

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Jusoh, Mohd Afifi, Mohd Zamri Ibrahim, Muhamad Zalani Daud, Aliashim Albani, and Zulkifli Mohd Yusop. "Hydraulic Power Take-Off Concepts for Wave Energy Conversion System: A Review." Energies 12, no. 23 (November 27, 2019): 4510. http://dx.doi.org/10.3390/en12234510.

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Анотація:

Ocean wave energy is one of the most abundant energy sources in the world. There is a wide variety of wave energy conversion systems that have been designed and developed, resulting from the different ways of ocean wave energy absorption and also depending on the location characteristics. This paper reviews and analyses the concepts of hydraulic power take-off (PTO) system used in various types of wave energy conversion systems so that it can be a useful reference to researchers, engineers and inventors. This paper also reviews the control mechanisms of the hydraulic PTO system in order to optimise the energy harvested from the ocean waves. Finally, the benefits and challenges of the hydraulic PTO system are discussed in this paper.

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R. S. Thomas and D. R. Buckmaster. "DEVELOPMENT OF A COMPUTER-CONTROLLED, HYDRAULIC, POWER TAKE-OFF (PTO) SYSTEM." Transactions of the ASAE 48, no. 5 (2005): 1669–75. http://dx.doi.org/10.13031/2013.19995.

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Gaspar, José F., Peter K. Stansby, Miguel Calvário, and C. Guedes Soares. "Hydraulic Power Take-Off concept for the M4 Wave Energy Converter." Applied Ocean Research 106 (January 2021): 102462. http://dx.doi.org/10.1016/j.apor.2020.102462.

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Jusoh, Mohd Afifi, Zulkifli Mohd Yusop, Aliashim Albani, Muhamad Zalani Daud, and Mohd Zamri Ibrahim. "Investigations of Hydraulic Power Take-Off Unit Parameters Effects on the Performance of the WAB-WECs in the Different Irregular Sea States." Journal of Marine Science and Engineering 9, no. 8 (August 20, 2021): 897. http://dx.doi.org/10.3390/jmse9080897.

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Анотація:

Hydraulic power take-off (HPTO) is considered to be one of the most effective power take-off schemes for wave energy conversion systems (WECs). The HPTO unit can be constructed using standard hydraulic components that are readily available from the hydraulic industry market. However, the construction and operation of the HPTO unit are more complex rather than other types of power take-off, as many components parameters need to be considered during the optimization. Generator damping, hydraulic motor displacement, hydraulic cylinder and accumulator size are among the important parameters that influence the HPTO performance in generating usable electricity. Therefore, the influence of these parameters on the amount of generated electrical power from the HPTO unit was investigated in the present study. A simulation study was conducted using MATLAB/Simulink software, in which a complete model of WECs was developed using the Simscape fluids toolbox. During the simulation, each parameters study of the HPTO unit were separately manipulated to investigate its effects on the WECs performance in five different sea states. Finally, the simulated result of the effect of HPTO parameters on the amount of generated electrical power from the HPTO unit in different sea states is given and discussed.

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Більше джерел

Дисертації з теми "Hydraulic Power Take-Off"

Yang, Limin. "Stochastic dynamic system analysis of wave energy converter with hydraulic power take-off, with particular reference to wear damage analysis." Doctoral thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for marin teknikk, 2011. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-13788.

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The study of the renewable energy has drawn increasing attention in the recent years. Wave energy with its relatively high power density is a major resource that has remained untapped until recently. Different types of wave energy converters have been proposed for extracting the energy from the waves. In this thesis, a heaving semi-submerged buoy, moving relative to a fixed reference to drive hydraulic power take-off, was studied. To meet stringent in-service and operational requirements, the components of a wave energy converter (WEC) need to have high levels of reliability and availability. Hence, it is necessary to develop mathematical models that enable a numerical solution with sufficient accuracy and computational efficiency, and apply these models to assess the energy capture and the safety and availability of the system based on relevant reliability theory. The studied wave energy converter system consists of several subsystems, i.e., a floating buoy, a hydraulic pump, check valves, transmission lines, accumulators, a hydraulic motor and an electric generator, where energy is converted between several energy domains, and each belongs to a different engineering discipline. An integrated dynamic model in the state space form was established for this system of components. The dynamic characteristic of the considered wave energy converter system was studied, with particular reference to high frequency oscillations (HFO) of the buoy and the transient pressures in the pipelines. High frequency oscillations (HFOs), as defined in this thesis, refer to the motions of the buoy that oscillates at frequencies much higher than those of the incident waves. HFOs were observed in the time interval when no fluid was pumped or sucked between the hydraulic pump and accumulators. This type of motion is mainly caused by the fluid compressibility of the hydraulic pump. The analytical solutions of the oscillating frequencies, which depend on the hydraulic cylinder parameters, were derived in this study. The results show that the HFOs contribute significantly to the wear damage of the hydraulic pump, especially to the wear loss of cylinder bore. Because of the notable effect on the wear estimation, a dynamic wave energy converter model that can describe the HFOs is developed in the thesis. The transient pressure in the pipeline, which accompanies any sudden change in the rate of fluid flow, was another detrimental load studied in the thesis. The magnitudes of the transient pressures can be many times larger than the normal operating pressure and may cause fatigue and catastrophic failures. This fact raises the question of how to predict and mitigate the pressure pulsations. In this study, pipeline dynamics were taken into account in the form of modal representations. In addition, to predict the opening and closing times of the valve operation, which directly affect the magnitude of the transient pressures, a dynamic model of the check valves is also introduced. By combining the subsystem models of pipelines and check valves with the models of other subsystems employed in the wave energy converter system, the transient pressures were calculated numerically. Moreover, the effect of the pipelines connected between the hydraulic pump and check valves on the electric power production is also investigated in this research work. The hydraulic pump, which converts the kinetic energy of the buoy into hydraulic energy of the working fluid, plays an important role in the proposed wave energy converter system. Wearing of the piston rings and cylinder bore significantly contribute to hydraulic pump failure. This research focuses on wear damage of the piston rings and cylinder bore under random sea state conditions. An abrasive wear model that considers the effect of the sealed pressure, lubrication condition, surface roughness, material properties, relative velocity and the cutting efficiency was developed. Based on the wear model and hypothesis of linear cumulative loss, a W - Tf approach (wear work rate versus time duration for wear damage growth till failure) was provided to estimate the piston ring wear resistance. By taking into account the occurrence probability of each sea state, a long-term wear damage estimation model was finally derived and given in the thesis. Because it is very time consuming to calculate the wear damage by considering all of the sea states, focus should be on the sea states that represent the most significant contribution to wear. In this thesis, the relative contribution of wear for the piston ring and cylinder bore from different sea states was calculated. The primary sea states contributing to wear can be found easily from the obtained figures. The last topic of this research work is to construct modal bond graphs for the transmission lines. To model a pipeline with fluid pressures and flow rates at its two ends (i.e., the upstream side and downstream side) as input-output variables, four possible boundary conditions—pressure inputs at both ends, flow rate inputs at both ends and the two cases of mixed inputs—should be taken into account. The pipeline dynamics can be approximately modelled with modal models, which can be represented in the bond graph forms. To derive the modal models, two methods, separation of variables (SOV) and rational transfer function (RTF*) may be used. In this thesis, modal bond graph representations were reviewed and new bond graph models were proposed for combinations of the solution methods and input-output configurations not yet presented in the literature, which include a bond graph for the two mixed input cases developed using the SOV technique and bond graphs for the other two cases (i.e., pressure inputs or flow rate inputs) constructed based on RTF solutions. It is found that the modal models derived by SOV and RTF have the same accuracy when the same number of modes is employed. With the developed bond graph models, the pipelines which are coupled with any other dynamic elements and systems can be modelled and analysed straightforwardly.

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Частини книг з теми "Hydraulic Power Take-Off"

Kalidoss, Sudharsan, and Arindam Banerjee. "Performance Evaluation of Floating Two-Body Wave Energy Converter with Hydraulic Power Take-Off System." In Lecture Notes in Civil Engineering, 883–97. Singapore: Springer Singapore, 2018. http://dx.doi.org/10.1007/978-981-13-3134-3_65.

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Calvário, M., J. Gaspar, and C. Soares. "Comparative study of lever mechanisms connected to oil-hydraulic power take-off systems." In Renewable Energies Offshore, 271–78. CRC Press, 2015. http://dx.doi.org/10.1201/b18973-40.

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"Modelling pump efficiency in a generic hydraulic Power Take-Off for wave energy point absorbers." In Maritime Technology and Engineering, 1247–56. CRC Press, 2014. http://dx.doi.org/10.1201/b17494-134.

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Gaspar, J., and C. Soares. "Modelling pump efficiency in a generic hydraulic Power Take-Off for wave energy point absorbers." In Maritime Technology and Engineering, 1233–41. CRC Press, 2014. http://dx.doi.org/10.1201/b17494-167.

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Тези доповідей конференцій з теми "Hydraulic Power Take-Off"

Yu, Yi-Hsiang, Nathan Tom, and Dale Jenne. "Numerical Analysis on Hydraulic Power Take-Off for Wave Energy Converter and Power Smoothing Methods." In ASME 2018 37th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/omae2018-78176.

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Анотація:

One of the primary challenges for wave energy converter (WEC) systems is the fluctuating nature of wave resources, which require the WEC components to be designed to handle loads (i.e., torques, forces, and powers) that are many times greater than the average load. This approach requires a much greater power take-off (PTO) capacity than the average power output and indicates a higher cost for the PTO. Moreover, additional design requirements, such as battery storage, are needed, particularly for practical electrical grid connection, and can be a problem for sensitive equipment (e.g., radar, computing devices, and sensors). Therefore, it is essential to investigate potential methodologies to reduce the overall power fluctuation while trying to optimize the power output from WECs. In this study, a detailed hydraulic PTO model was developed and coupled with a time-domain hydrodynamics model (WEC-Sim) to evaluate the PTO efficiency for WECs and the trade-off between power output and fluctuation using different power smoothing methods, including energy storage, pressure relief mechanism, and a power-based setpoint control method. The study also revealed that the maximum power fluctuation for WECs can be significantly reduced by one order of magnitude when these power smoothing methods are applied.

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Plagge, Amanda M., Lee Jestings, and Brenden P. Epps. "Next-Generation Hydrokinetic Power Take-Off via a Novel Variable-Stroke Hydraulic System." In ASME 2014 33rd International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/omae2014-24095.

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Hydrokinetic power generation has the potential to supply nearly ten percent of the United States annual energy demand. However, the hydrokinetic generation has lagged behind other renewable energy technologies, and many engineering challenges remain. Here, we consider the impacts of using a hydraulic power transfer system for hydrokinetic power generation. The incorporation of hydraulic power transfer into hydrokinetic systems has the potential to increase durability, reduce required maintenance, and increase power-to-weight ratio, all of which would lower the overall levelized cost of energy (LCOE). In the proposed system, patented low friction, variable-stroke hydraulic pump and motor pairs would allow energy to be harvested efficiently throughout the full range of water velocities in either tidal or riverine flows and with any type of rotary prime mover. A full system characterization is provided, along with a calculation of expected LCOE and a considered analysis of the applicability of hydraulic PTO systems as a way to advance commercial hydrokinetic power generation.

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Imai, Yasutaka, Shuichi Nagata, Tengen Murakami, and Da-Wei Chen. "Design of a hydraulic power take-off test rig for wave energy converters." In 2016 Techno-Ocean (Techno-Ocean). IEEE, 2016. http://dx.doi.org/10.1109/techno-ocean.2016.7890708.

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Gao, Hong, and Ruizhi Liang. "Performance investigation of a hydraulic power take-off system for wave energy conversion." In 2019 IEEE 8th International Conference on Fluid Power and Mechatronics (FPM). IEEE, 2019. http://dx.doi.org/10.1109/fpm45753.2019.9035801.

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Sun, Ke, Wenke Ge, Liang Luo, Hui Liang, Chicheng Xu, Jianxing Leng, Zhuoli Yuan, and Haocai Huang. "Research on the hydraulic power take-off unit of a hybrid wave energy converter." In OCEANS 2016 - Shanghai. IEEE, 2016. http://dx.doi.org/10.1109/oceansap.2016.7485510.

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Bjarte-Larsson, Torkel, Per Magne Lillebekken, Jo̸rgen Hals, and Johannes Falnes. "Model Experiment on an OWC-Type Wave-Energy Converter With Hydraulic Power Take-Off." In ASME 2002 21st International Conference on Offshore Mechanics and Arctic Engineering. ASMEDC, 2002. http://dx.doi.org/10.1115/omae2002-28171.

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Анотація:

A wave-energy converter of the OWC type is described, in which the absorbed wave energy is converted to useful energy by means of a hydraulic power take-off. Means are provided to enable the float to be latched for phase control. The float is connected to a piston pump, which pumps water from the level of the water in the wave channel to a higher level, which is adjustable. By means of measurements from three wave gauges (two on the upstream side and one on the downstream side) the incident wave energy and the absorbed wave energy are derived. For a down-scaled laboratory model, resonance is obtained with an incident sinusoidal wave of period 1 s. With optimum load, the converted useful hydraulic energy is a fraction of 0.2 of the incident wave energy. The absorbed wave energy is then 0.6 units of the incident wave energy. With wave period 2 s and optimum load, these energy fractions are 0.03 and 0.13, which are increased to 0.05 and 0.21, respectively, when latching control is applied.

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Calvário, M., J. Gaspar, A. Sinha, and C. Guedes Soares. "Optimization of an oil-hydraulic Power Take-Off system based on an adaptable mechanism interface." In Proceedings of Renew 2016, 2nd International Conference on Renewable Energies Offshore. Taylor & Francis Group, 6000 Broken Sound Parkway NW, Suite 300, Boca Raton, FL 33487-2742: CRC Press, 2016. http://dx.doi.org/10.1201/9781315229256-53.

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Verbrugghe, Tim, Andreas Kortenhaus, and Julien De Rouck. "Numerical modelling of control strategies and accumulator effect of a hydraulic power take-off system." In OCEANS 2015 - Genova. IEEE, 2015. http://dx.doi.org/10.1109/oceans-genova.2015.7271736.

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Tul Huda Ahmad, Nur Hafizah, Mohd Zamri Ibrahim, Siti Juwairiyah A. Rahman, Aliashim Albani, and Safina Mohad. "The Development of Wave Energy Converter System Using Hydraulic Power Take Off at Terengganu Shoreline." In 2018 International Conference and Utility Exhibition on Green Energy for Sustainable Development (ICUE). IEEE, 2018. http://dx.doi.org/10.23919/icue-gesd.2018.8635780.

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Engin, Celalettin Dogukan, and Aydin Yesildirek. "Designing and modeling of a point absorber wave energy converter with hydraulic power take-off unit." In 2015 4th International Conference on Electric Power and Energy Conversion Systems (EPECS). IEEE, 2015. http://dx.doi.org/10.1109/epecs.2015.7368507.

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