HVDC Connection of Offshore Wind Farms to the Transmission System

Abstract

This paper presents a technical and economic analysis to evaluate the benefits and drawbacks of grid connecting offshore wind farms through a dc link. A first case, concerning a 100-MW wind farm, is thoroughly investigated and cases of larger wind farms (200 and 500 MW) are presented. Three different transmission solutions are compared: 150-kV ac, 400-kV ac, and highvoltage dc based on voltage sourced converters (VSC-HVDC). After a brief overview of the features of these connection solutions, the related operational aspects are evaluated. An economic assessment compares the dc connection option to the ac alternatives, taking into account the investment, operation, and maintenance costs, and the negative valorization of losses and energy not supplied. 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.Index Terms-DC power transmission, interconnected power systems, power cables, power transmission economics, wind power generation.

Multichoice Control Strategy for VSC-HVdc

“…Di erent studies have shown the capability of VSC-HVdc enhancing the stability of power systems [7], [8], providing voltage support [9], [10] and its application in the connection of wind farms [11], [12], just to mention some references.…”

Impact of DFIG Based Offshore Wind Farms Connected Through VSC-HVDC Link on Power System Stability

“…In this case, OWF cannot contribute to the onshore fault. In addition, VSC-HVDC can provide fast control of both active and reactive power independently [6,8].…”

Primary and secondary power control of multiterminal HVDC grids

“…For Back-toBack HVDC systems, the voltage is controlled using an unique local control that maintain constant ot [13]. For M-HVDC applications other controllers and controllers coordination are used [14], but the most studied controller is the droop controller.…”