1. ANALYSIS AND COMPARISON OF MEDIUM VOLTAGE HIGH POWER
DC/DC CONVERTERS FOR OFFSHORE WIND ENERGY SYSTEMS
ABSTRACT:
Offshore wind farm with an internal medium-voltage dc (MVDC)-grid collection connected HVDC
transmission may be an option to harvest offshore wind energy. High-power MV dc/dc converters with highstep-up conversion ratios are the key components for the internal MVDC grid. In this paper, a highefficiency step-up resonant switched-capacitor converter for offshore wind energy system is studied, which
is characterized by the soft-switching condition for all switches and diodes. This significantly reduces
switching losses and higher switching frequency is feasible to reduce the overall system volume and weight.
The comparisons with other two kinds of topologies are also presented; moreover, the possible specification
requirements of high power MV dc/dc converters are analyzed and set. The operation principle of the
proposed converter has been successfully verified by simulation and experiment results.