授課教師 : 吳元康 老師 學生 : 詹博雄 HVDC Connection of Offshore Wind Farms to the Transmission System

Introduction This paper presents a technical and economic analysis to evaluate the benefits and drawbacks of grid connecting offshore wind farms through a dc link.

TECHNICAL ANALYSIS OF THE CONNECTION OPTIONS caseTransmission typeFailure mode 100MW ACLink DCLink 250MW ACLink DCLink 500MW AC 150 kV HV AC cable Transformer AC 400 kV HV AC cable Transformer DC Stations/cable Transformer

100MW AC

100MW DC

200MW AC

500MW AC

TECHNICAL ANALYSIS OF THE CONNECTION OPTIONS

ECONOMIC ANALYSIS: COMPARISON OF THE CONNECTION OPTIONS O&M: operation and maintenance ENS : the value of losses and of energy not supplied

ECONOMIC ANALYSIS: COMPARISON OF THE CONNECTION OPTIONS This especially impacts the economics of the 100-MW wind farm. Economic assessment includes sensitivity analyses of parameters, which could impact the 100-MW wind farm: distance, component costs, dc converter reliability, and dc converter losses.

ECONOMIC ANALYSIS: COMPARISON OF THE CONNECTION OPTIONS

CONCLUSION For all the case studies, the HVDC solution is more expensive than the ac, partly because of higher total investment costs at the considered connection distance of 60 km. Nevertheless, the results of sensitivity analyses performed for various parameters (connection distance, cost of cable protection, and cost and reliability of converter stations) show that HVDC appears to be the cheapest option to connect a 100-MW wind farm at distances greater than 90 km to the shore.

CONCLUSION Evaluations performed within this research activity and the present experience with VSC-HVDC connection of offshore oil/gas platforms allows us to believe that HVDC is a promising technology with growth potential for applications in the connection of offshore wind farms.