TY - JOUR
T1 - Optimized Integrated Harmonic Filter Inductor for Dual-Converter-Fed Open-End Transformer Topology
AU - Gohil, Ghanshyamsinh Vijaysinh
AU - Bede, Lorand
AU - Teodorescu, Remus
AU - Kerekes, Tamas
AU - Blaabjerg, Frede
PY - 2017/3
Y1 - 2017/3
N2 - Many high power converter systems are often connected to the medium voltage network using a step-up transformer. In such systems, the converter-side windings of the transformer can be configured as an open-end and multi-level voltage waveforms can be achieved by feeding these open-end windings from both ends using the two-level dual-converter. An $LCL$ filter with separate converter-side inductors for each of the converter is commonly used to attenuate the undesirable harmonic frequency components in the grid current. The magnetic integration of the converter-side inductors is presented in this paper, where the flux in the common part of the magnetic core is completely canceled out. As a result, the size of the magnetic component can be significantly reduced. A multi-objective design optimization is presented, where the energy loss and the volume are optimized. The optimization process takes into account the yearly load profile and the energy loss is minimized, rather than minimizing the losses at a specific operating point. The size reduction achieved by the proposed inductor is demonstrated through a comparative evaluation. Finally, the analysis is supported through simulations and experimental results.
AB - Many high power converter systems are often connected to the medium voltage network using a step-up transformer. In such systems, the converter-side windings of the transformer can be configured as an open-end and multi-level voltage waveforms can be achieved by feeding these open-end windings from both ends using the two-level dual-converter. An $LCL$ filter with separate converter-side inductors for each of the converter is commonly used to attenuate the undesirable harmonic frequency components in the grid current. The magnetic integration of the converter-side inductors is presented in this paper, where the flux in the common part of the magnetic core is completely canceled out. As a result, the size of the magnetic component can be significantly reduced. A multi-objective design optimization is presented, where the energy loss and the volume are optimized. The optimization process takes into account the yearly load profile and the energy loss is minimized, rather than minimizing the losses at a specific operating point. The size reduction achieved by the proposed inductor is demonstrated through a comparative evaluation. Finally, the analysis is supported through simulations and experimental results.
KW - Wind turbine
KW - Wind energy systems
KW - Wind energy conversion system
KW - Harmonic filter design
KW - Harmonic filter
KW - LCL filter
KW - Multi-objective optimization
KW - Optimized filter design
KW - High power converters
KW - Dual-converter
KW - Open-end transformer
KW - Open-end
KW - Water cooled inductor
KW - Liquid cooling
U2 - 10.1109/TPEL.2016.2562679
DO - 10.1109/TPEL.2016.2562679
M3 - Journal article
SN - 0885-8993
VL - 32
SP - 1818
EP - 1831
JO - I E E E Transactions on Power Electronics
JF - I E E E Transactions on Power Electronics
IS - 3
ER -