Dynamic analysis of DC-DC converter internal to an offshore wind farm

Abstract

This paper investigates the dynamic performance of an active rectifier integrated into a wind park. The small changes in the DC current and the DC voltage are examined. The small variations are caused by the miniature power flow unbalance between the offshore wind park and the grid land. Internal DC collector is considered into the wind park, which provides an internal DC medium voltage bus. The AC output signal from the wind generator to the internal DC collector or DC bus is regulated through active rectifier. An active rectifier is a cascade connection of an uncontrolled full bridge diode rectifier and a controlled DC-DC boost converter. The small changes in the DC current and DC voltage due to power flow unbalance are analysed across the boost converter. The way in which these small variations affect the internal medium DC voltage is determined. The results are presented in the form of small signal transfer functions and are evaluated with MATLAB software.