Abstract
The equivalent model of offshore DC power collection network for the harmonic susceptibility study is proposed based on the discrete time-domain modelling technique and frequency scan approach in the frequency domain. The proposed methodology for modelling a power converter and a DC collection system in the frequency domain can satisfy harmonic studies of any configuration of wind farm network and thereby find suitable design of power components and array network. The methodology is intended to allow studies on any configuration of the wind power collection, regardless of choice of converter topology, array cable configuration, and control design. To facilitate harmonic susceptibility study, modelling DC collection network includes creating the harmonic model of the DC turbine converter and modelling the array network. The current harmonics within the DC collection network are obtained in the frequency domain to identify the resonance frequency of the array network and potential voltage amplification issues, where the harmonic model of the turbine converter is verified by the comparison of the converter switching model in the PLECS™ circuit simulation tool and laboratory test bench, and show a good agreement.
Highlights
Offshore wind power is becoming an important energy resource in Europe
Depending on the configuration of the wind power plant, every power collection system has its own inherent resonance behavior. e network, which is rich in the harmonic current, can increase the power losses and the stress of power components and cause unpredicted equipment trip. e resonance behavior inside the collection network is affected by properties of the array cable, filter designs, converter topologies, and PWM schemes. erefore, the objective of this paper is to develop a methodology to identify potential harmonic resonant problems in the DC collection network
A schematic of the setup of the DC wind turbine converter for SRC# is depicted in Figure 17. e down-scale prototype circuit with 216 VDC (VLVDC) to 400 VDC (VMVDC) DC wind turbine converter is built to verify the harmonic distribution of the turbine converter. e wind turbine converters, whatever AC or DC turbines, are the boost structures in order to increase the efficiency of power transmission
Summary
Offshore wind power is becoming an important energy resource in Europe. electrical power losses are always a concern in the operation of wind farm with longrange power transmission. A series resonant converter topology (named SRC#) shown in Figure 3 is selected as the candidate for DC power conversion via ±50 kVDC MVDC array network. Via the diode rectifier and the output filter, the current (or power) is delivered to the medium-voltage network, VMVDC Up to this point, there is no difference in the operation compared to a constant frequency and phase-shift control of classical SRC, which is usually operated in the super resonant mode, to achieve ZVS at turn on. 3. Linearized Model and Closed-Loop Control of Series Resonant Converter e objective of the study is to understand the harmonics distribution of offshore DC wind farm and how the DC wind turbines are affected by harmonics from the MVDC gird. E design criterion has been implemented to select the parameters for the different operation points (different output powers of the DC wind turbine), which have enough gain margin and the phase margin to deal with the parameter uncertainty and variation
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
