Measurement of Parasitic Inductances in the Bus-Bar Assembly of a High Power Voltage Source Converter

Insulated gate bipolar transistor (IGBT) based voltage source converters use copper plates with insulating sheets in between them (sandwich bus-bar arrangement) for connecting the different device terminals in the power circuit. In such converters, the parasitic inductances in the power circuit are crucial as they cause overvoltage spikes across the device. Also, the parasitics affect the current sharing between IGBTs when they are connected in parallel in high power converters. The conduction path through plates and fasteners in the bus-bar assembly is three-dimensional and quite complex, making analytical evaluation of the stray inductance quite challenging. The first objective here is to present a simple experimental setup and experimental procedure, which are convenient for power electronic engineers, to measure the bus-bar inductance. The next objective is to carry out experimental studies on the inductances offered by different components and sub-assemblies in a bus-bar assembly. This includes evaluation of inductances of the different conduction paths in typical bus-bar plates. The third objective is to experimentally evaluate the parasitic inductances in the bus-bar assembly of a commercial 250 kVA high power converter. Each leg of this converter consists of two 300 A/1200 V IGBTs connected in parallel. The effective inductance seen by the individual device modules are determined experimentally.

[1]  G. Narayanan,et al.  Minimum switching loss pulse width modulation for reduced power conversion loss in reactive power compensators , 2014 .

[2]  Marco Liserre,et al.  Grid-Filter Design for a Multimegawatt Medium-Voltage Voltage-Source Inverter , 2011, IEEE Transactions on Industrial Electronics.

[3]  Nan Chen,et al.  Dynamic characterization of parallel-connected high-power IGBT modules , 2013, 2013 IEEE Energy Conversion Congress and Exposition.

[4]  Guozhu Chen,et al.  Study and Design of Noninductive Bus bar for high power switching converter , 2006, 2006 CES/IEEE 5th International Power Electronics and Motion Control Conference.

[5]  Weidong Xiao,et al.  Design and optimization of laminated busbar to reduce transient voltage spike , 2012, 2012 IEEE International Symposium on Industrial Electronics.

[6]  J. Roudet,et al.  Busbar Design: How to Spare Nanohenries ? , 2006, Conference Record of the 2006 IEEE Industry Applications Conference Forty-First IAS Annual Meeting.

[7]  Keiji Wada,et al.  Design and analysis of a bus bar structure for a medium voltage inverter , 2011, Proceedings of the 2011 14th European Conference on Power Electronics and Applications.

[8]  A. Tenconi,et al.  Low stray inductance bus bar design and construction for good EMC performance in power electronic circuits , 2000 .

[9]  G. Narayanan,et al.  Experimental investigation on switching characteristics of high-current insulated gate bipolar transistors at low currents , 2014, 2014 IEEE 2nd International Conference on Electrical Energy Systems (ICEES).

[10]  Thomas A. Lipo,et al.  Co-axial current transformer for test and characterization of high power semiconductor devices under hard and soft-switching , 1999 .

[11]  Zhengming Zhao,et al.  The large-size low-stray-parameter planar bus bar for high power IGBT-based inverters , 2012, 2012 15th International Conference on Electrical Machines and Systems (ICEMS).

[12]  Hui Zhang,et al.  Planar bus bar optimum design in high-power converters based on FEM analysis , 2010, The 2nd International Symposium on Power Electronics for Distributed Generation Systems.

[13]  G. Narayanan,et al.  Experimental investigation on switching characteristics of IGBTs for traction application , 2012, 2012 IEEE International Conference on Power Electronics, Drives and Energy Systems (PEDES).

[14]  M. Tobita,et al.  Development of a multiple series-connected IGBT converter for large-capacity STATCOM , 2010, The 2010 International Power Electronics Conference - ECCE ASIA -.

[15]  Zhengming Zhao,et al.  Design, simulation and analysis of the low stray inductance bus bar for voltage source inverters , 2011, 2011 International Conference on Electrical Machines and Systems.