The 15kV /20A, 4H-SiC n-IGBT is the state-of-the-art high voltage power semiconductor device. The transformerless intelligent power substation (TIPS) [1] for 13.8kV grid interfacing is built using this device. It is proposed to use a three-phase, three-level, diode clamped topology as the front end converter (FEC) in TIPS. A modular-leg structure has been employed for FEC. In modular-leg structure, each phase-leg will have its own DC-link capacitors and a low inductance bus-bar. However, modular-leg structure adds complexity in DC bus over-load protection, which is studied in this paper. Experimental results of modular-leg converter at 3kV DC link voltage and scale down prototype of AC switch for DC bus fault protection are presented. © 2013 IEEE.

Kamalesh Hatua

Department of Electrical Engineering

Dc link capacitor

DC-link voltages

Fault protection

FRONT-END CONVERTERS

HIGH VOLTAGE POWER

INTELLIGENT POWER

LOW INDUCTANCE

Transformerless

Energy conversion

Power electronics

Silicon carbide

Power converters

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.

IIT Madras

15 kV SiC IGBT based three-phase three-level modular-leg power converter

2013 IEEE Energy Conversion Congress and Exposition, ECCE 2013

Recently, with the emergence of Wide Bandgap semiconductor devices having higher blocking voltage capabilities and higher switching speed, ac-dc converters for Medium Voltage (MV) and Low Voltage (LV) dc micro-grid applications are becoming popular. In this paper, the first time experimental demonstration of such a 3-phase, isolated ac-dc power converter based on the newly developed 15 kV/40 A SiC IGBT is presented for 4.16 kV ac distribution grid interface. The presented converter consists of two bidirectional stages - the 4.16 kV ac to 8 kV dc front end converter followed by an 8 kV dc to 480 V dc dual active bridge converter with high frequency isolation. These stages are switched at 5 kHz and 10 kHz respectively. The converter design is presented along with experimental validation on a prototype at 9.6 kW. © 2015 IEEE.

2015 IEEE Energy Conversion Congress and Exposition, ECCE 2015

Three-phase 4.16 kV medium voltage grid tied AC-DC converter based on 15 kV/40 a SiC IGBTs

Transformerless Intelligent Power Substation (TIPS) is a 3-phase Solid State Transformer (SST) to interconnect 13.8 kV, 3-phase distribution grid with 480 V, 3-phase utility grid. The concept of TIPS was proposed as a solid state alternative to the conventional line frequency transformer. Various advantages of TIPS include unity power factor operation, controlled bidirectional power flow capability, reactive power compensation to improve grid voltage profile under necessary conditions, high frequency d.c link based isolation, small size and weight due to Silicon Carbide (SiC) devices, and renewable energy integration. This paper focuses on the system integration and hardware demonstration of the functions of TIPS at lower voltage and power levels. In addition, it focuses on various operational strategies like smooth start-up/shut-down scheme, stability criteria at the high voltage d.c link, fault protection for the various modules of TIPS, power quality improvement and performance under sudden load transients. Experimental results are given for each module separately and for fully integrated TIPS. © 2014 IEEE.

Conference Proceedings - IEEE Applied Power Electronics Conference and Exposition - APEC

Experimental validation of the steady state and transient behavior of a transformerless intelligent power substation

2012 IEEE Energy Conversion Congress and Exposition (ECCE)

High performance, ultra high voltage 4H-SiC IGBTs

Efficiency Comparison of AC-Link and TIPS (SST) Topologies based on accurate device models

2011 IEEE Energy Conversion Congress and Exposition

10 kV, 120 A SiC half H-bridge power MOSFET modules suitable for high frequency, medium voltage applications

2008 34th Annual Conference of IEEE Industrial Electronics

Recent progress in SiC DMOSFETs and JBS diodes at Cree

2008 IEEE Industry Applications Society Annual Meeting

Design and Evaluation Criteria for High Power Drives

Journal	2013 IEEE Energy Conversion Congress and Exposition, ECCE 2013
Open Access	No