# Optimal Constant DC Link Voltage Operation of a Wave Energy Converter

^{*}

## Abstract

**:**

## 1. Introduction

## 2. Strategies for Maximum Energy Absorption of a Point Absorber

## 3. Constant DC-link Damping

**Figure 3.**Examples of WEC velocity and damping force, using a constant DC-link at 50 V and 200 V. (

**a**) Comparison of translator velocities; (

**b**) Comparison of Reaction forces.

## 4. Research Site Specifics

## 5. Simulation Model

**Figure 7.**Buoy characteristics. (

**a**) Hexagonal torus buoy; (

**b**) Excitation impulse response; (

**c**) Radiation impulse response.

Rated power | 23.1 kW at 0.7 m/s |

Rated phase voltage | 450 V at 0.7 m/s |

Phase winding resistance | 1.0 Ohm |

Phase winding inductance | 20 mH |

Pole widtd | 52 mm |

B-field | 1.73 Tesla |

Sea cable resistance | 0.2 Ω/km |

Sea cable capacitance | 50 $\mu F$/km |

Buoy mass | 2500 kg |

Translator mass | 2700 kg |

Translator lengtd | 2 m |

Stator lengtd | 2 m |

Free stroke lengtd | ±1 m |

Max. stroke lengtd | ±1.25 m |

## 6. Simulation Results and Discussion

**Figure 8.**Optimal DC-level keeping either ${H}_{S}$ or ${T}_{E}$ constant. (

**a**) ${H}_{S}$ = 0.7 m; (

**b**) ${H}_{S}$ = 3.0 m; (

**c**) ${T}_{E}$ = 4.5 s; (

**d**) ${T}_{E}$ = 6.5 s.

**Figure 9.**Optimal ${V}_{DC}$ as a function of the sea state parameters. (

**a**) Optimal DC-level and the contours of the available energy; (

**b**) Generated power operating at optimal ${V}_{DC}$ for the different sea states.

## 7. Conclusions

## Acknowledgements

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**MDPI and ACS Style**

Kurupath, V.; Ekström, R.; Leijon, M.
Optimal Constant DC Link Voltage Operation of a Wave Energy Converter. *Energies* **2013**, *6*, 1993-2006.
https://doi.org/10.3390/en6041993

**AMA Style**

Kurupath V, Ekström R, Leijon M.
Optimal Constant DC Link Voltage Operation of a Wave Energy Converter. *Energies*. 2013; 6(4):1993-2006.
https://doi.org/10.3390/en6041993

**Chicago/Turabian Style**

Kurupath, Venugopalan, Rickard Ekström, and Mats Leijon.
2013. "Optimal Constant DC Link Voltage Operation of a Wave Energy Converter" *Energies* 6, no. 4: 1993-2006.
https://doi.org/10.3390/en6041993