Slide 1

: : HVDC Connection of Offshore Wind Farms to the Transmission System

Slide 2

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.

Slide 3

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

Slide 4

100MW AC

Slide 5

100MW DC

Slide 6

200MW AC

Slide 7

500MW AC

Slide 8

TECHNICAL ANALYSIS OF THE CONNECTION OPTIONS

Slide 9

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

Slide 10

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.

Slide 11

ECONOMIC ANALYSIS: COMPARISON OF THE CONNECTION OPTIONS

Slide 12

Slide 13

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.

Slide 14

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.