# Modeling, Experimental Analysis, and Optimized Control of an Ocean Wave Energy Conversion System in the Yellow Sea near Lianyungang Port

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## Abstract

**:**

## 1. Introduction

## 2. Motion Model of Double-Buoy OWECS

#### 2.1. Vertical Direction Speed of Buoy

#### 2.2. Analysis of Energy Conversion Efficiency

## 3. Experimental Results

#### 3.1. The Specific Structure of Double-Buoy OWECS

#### 3.2. Output Voltage and Power Analysis

## 4. Efficiency Improvement of Double-Buoy OWECS

#### 4.1. The Relationship between Load Force and q-Axis Current of Linear Generator

#### 4.2. Optimized Control of Double-Buoy OWECS

## 5. Discussion

## 6. Conclusions

## Author Contributions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Conflicts of Interest

## References

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Outer Diameter | 2.4 m | |
---|---|---|

Inner diameter | 1.0 m | |

Outer buoy | Height | 1.8 m |

Draft (${h}_{1}$) | 0.771 m | |

Outer diameter | 0.83 m | |

Inner buoy | Height | 7.9 m |

Draft (${h}_{2}$) | 6.059 m |

Wave Amplitude (m) | Wave Period (s) | Power (kW) | Efficiency | ||
---|---|---|---|---|---|

Ocean Wave (Kinetic Energy) | Outer Buoy | Inner Buoy | |||

0.7 | 3 | 10.7275 | 3.4206 | 0.5225 | 27.02% |

0.7 | 5 | 17.879 | 7.0680 | 0.5615 | 36.39% |

0.7 | 7 | 25.0305 | 6.3139 | 0.5258 | 23.12% |

0.7 | 8 | 28.6065 | 5.9704 | 0.5189 | 19.06% |

Season | $\mathbf{Average}\text{}\mathbf{Wave}\text{}\mathbf{Periods}\text{}\mathit{T}$ | $\mathbf{Average}\text{}\mathbf{Angular}\text{}\mathbf{Frequency}\text{}\mathit{\omega}$ |
---|---|---|

Spring | 5–5.5 s | 1.1424–1.2566 rad/s |

Summer | 5.5–6 s | 1.0472–1.1424 rad/s |

Autumn | 5–5.5 s | 1.1424–1.2566 rad/s |

Winter | 5–5.5 s | 1.1424–1.2566 rad/s |

Wave Amplitude (m) | Wave Period (s) | Power (kW) | Efficiency | |
---|---|---|---|---|

Ocean Wave (Kinetic Energy) | Linear Generator | |||

0.7 | 5.5 | 19.667 | 1.176 | 5.98% |

0.75 | 8.5 | 34.8915 | 1.187 | 3.4% |

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**MDPI and ACS Style**

Chen, Z.; Li, X.; Cui, Y.; Hong, L.
Modeling, Experimental Analysis, and Optimized Control of an Ocean Wave Energy Conversion System in the Yellow Sea near Lianyungang Port. *Energies* **2022**, *15*, 8788.
https://doi.org/10.3390/en15238788

**AMA Style**

Chen Z, Li X, Cui Y, Hong L.
Modeling, Experimental Analysis, and Optimized Control of an Ocean Wave Energy Conversion System in the Yellow Sea near Lianyungang Port. *Energies*. 2022; 15(23):8788.
https://doi.org/10.3390/en15238788

**Chicago/Turabian Style**

Chen, Zhongxian, Xu Li, Yingjie Cui, and Liwei Hong.
2022. "Modeling, Experimental Analysis, and Optimized Control of an Ocean Wave Energy Conversion System in the Yellow Sea near Lianyungang Port" *Energies* 15, no. 23: 8788.
https://doi.org/10.3390/en15238788