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Study on Hydraulic System Efficiency of Heaving-Buoy Wave Energy Converter

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Abstract

The hydraulic system is the key component in the widely used wave energy converters (WEC). In this paper, we theoretically analyze and describe our investigation of the efficiency of the hydraulic system by simulation and model testing of the combined heaving-buoy WEC. We derive a new governing equation that includes nonlinear hydraulic resistance in the power take-off (PTO). We conducted a physical model experiment based on a 100-kW prototype and applied a hydraulic system with an energy accumulator. The model test results reveal an important parameter related to efficiency with respect to nonlinear hydraulic resistance. We also studied the relationship between the efficiency and the initial conditions. Finally, based on our numerical simulation results, we discuss the effect on efficiency of the gas content of the hydraulic fluid and ways to reduce its impact.

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Acknowledgements

The authors would like to acknowledge the support of the Marine Renewable Energy Project (No. GHME2016 YY02), the National Natural Science Foundation of China (Nos. 41376100 and41706100), the Shandong Provincial Natural Science Key Basic Program (No. ZR2017ZA0202), and the Fundamental Research Funds for the Central Universities (No. 201564005).

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Authors and Affiliations

  1. College of Engineering, Ocean University of China, Qingdao, 266100, China

    Hongda Shi, Chenyu Zhao, Zhen Liu & Feifei Cao

  2. Shandong Provincial Key Laboratory of Ocean Engineering, Qingdao, 266100, China

    Hongda Shi & Zhen Liu

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  1. Hongda Shi
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  2. Chenyu Zhao
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  3. Zhen Liu
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  4. Feifei Cao
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Correspondence to Hongda Shi.

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Shi, H., Zhao, C., Liu, Z. et al. Study on Hydraulic System Efficiency of Heaving-Buoy Wave Energy Converter. J. Ocean Univ. China 17, 1044–1052 (2018). https://doi.org/10.1007/s11802-018-3668-6

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  • DOI: https://doi.org/10.1007/s11802-018-3668-6

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