@inproceedings{madhusoodhanan_bhattacharya_hatua_2014, title={A unified control scheme for harmonic elimination in the front end converter of a 13.8 kV, 100 kVA transformerless intelligent power substation grid tied with LCL filter}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84900448559&partnerID=MN8TOARS}, DOI={10.1109/apec.2014.6803424}, abstractNote={This paper proposes a simple control scheme to eliminate the lower order harmonics in the line currents of the Front End Converter (FEC) of a 100 kVA Transformerless Intelligent Power Substation (TIPS) connected to the medium voltage (13.8 kV) grid through an LCL filter. Due to medium voltage (13.8 kV) and low power (100 kVA) specification for the FEC, the control technique needs to be specially designed to control very low magnitude of line current (4.2 A rms). Lower order harmonics are present in the grid current due to dead time in the FEC and grid voltage harmonics. Low switching frequency along with the medium voltage and low power levels results in a filter capacitor value that offers low impedance to the lower order harmonic currents. This lower order harmonic current flow through the filter capacitor limits the power that can be delivered by the converter due to lower current rating of the FEC. It also pollutes the control loop and affect system stability. This paper proposes a simple unified control scheme with harmonic current elimination under such conditions. The control scheme eliminates these harmonics in the grid current by regulating the harmonics in the filter capacitor voltage and inductor currents, both on grid side and converter side. System modeling, simulation and experimental results validate the proposed control scheme.}, booktitle={Conference Proceedings - IEEE Applied Power Electronics Conference and Exposition - APEC}, author={Madhusoodhanan, S. and Bhattacharya, Subhashish and Hatua, K.}, year={2014}, pages={964–971} }
 @inproceedings{moballegh_madhusoodhanan_bhattacharya_2014, title={Evaluation of high voltage 15 kV SiC IGBT and 10 kV SiC MOSFET for ZVS and ZCS high power DC -DC converters}, booktitle={2014 international power electronics conference (ipec-hiroshima 2014 - ecce-asia)}, author={Moballegh, S. and Madhusoodhanan, S. and Bhattacharya, S.}, year={2014}, pages={656–663} }
 @inproceedings{madhusoodhanan_tripathi_kadavelugu_hazra_patel_mainali_bhattacharya_hatua_2014, title={Experimental validation of the steady state and transient behavior of a transformerless intelligent power substation}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84900439832&partnerID=MN8TOARS}, DOI={10.1109/apec.2014.6803809}, abstractNote={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.}, booktitle={Conference Proceedings - IEEE Applied Power Electronics Conference and Exposition - APEC}, author={Madhusoodhanan, S. and Tripathi, A. and Kadavelugu, A. and Hazra, S. and Patel, D. and Mainali, K. and Bhattacharya, Subhashish and Hatua, K.}, year={2014}, pages={3477–3484} }
 @inproceedings{patel_chattopadhyay_madhusoodhanan_bhattacharya_sawant_chandorkar_2014, title={Flux vector modulation for single-phase inverter with LC output filter}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84900463911&partnerID=MN8TOARS}, DOI={10.1109/apec.2014.6803510}, abstractNote={The inverter often connects to load or grid through inductor-capacitor (LC) filter for feeding the filtered voltage and current. The carrier based modulation techniques, such as sinusoidal pulse width modulation (SPWM) and space vector modulation (SVM), require some kind of current control in LC filter connected inverter to damp out the LC resonance. The major advantage of flux vector modulation for the inverter with output LC filter is that the voltage control loop alone can damp out the resonance of LC filter. Hence, there is no need to use extra passive components or active damping controller. In this paper, the flux vector modulation for single-phase voltage source inverter (VSI) is proposed. The theoretical development and the digital implementation steps of flux vector modulation are described. The synchronously rotating reference frame (SRRF) proportional-integral (PI) controller is used for output voltage control for stand-alone operation of inverter. The single-phase inverter with output LC filter in stand-alone mode controlled by only voltage control loop with the flux vector modulation is validated through laboratory experiments.}, booktitle={Conference Proceedings - IEEE Applied Power Electronics Conference and Exposition - APEC}, author={Patel, D.C. and Chattopadhyay, R. and Madhusoodhanan, S. and Bhattacharya, Subhashish and Sawant, R.R. and Chandorkar, M.C.}, year={2014}, pages={1530–1536} }
 @inproceedings{madhusoodhanan_tripathi_patel_mainali_kadavelugu_hazra_bhattacharya_hatua_2014, title={Solid State Transformer and MV grid tie applications enabled by 15 kV SiC IGBTs and 10 kV SiC MOSFETs based multilevel converters}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84906706613&partnerID=MN8TOARS}, DOI={10.1109/ipec.2014.6869800}, abstractNote={Recently, medium voltage SiC devices have been developed which can be used for grid tie applications at medium voltage. Two such devices - 15 kV SiC IGBT and 10 kV SiC MOSFET have opened up the possibility of looking into different converter topologies for medium voltage distribution grid interface. These can be used in medium voltage drives, active filter applications or as the active front end converter for Solid State Transformers (SST). Transformer-less Intelligent Power Substation (TIPS) is one such application for these devices. TIPS is proposed as a 3-phase SST interconnecting 13.8 kV distribution grid with 480 V utility grid. The Front End Converter (FEC) of TIPS is made up of 15 kV SiC IGBTs. This paper focuses on the advantages, design considerations and challenges associated with the operation of converters using these devices keeping TIPS as the topology of reference.}, booktitle={2014 International Power Electronics Conference, IPEC-Hiroshima - ECCE Asia 2014}, author={Madhusoodhanan, S. and Tripathi, A. and Patel, D. and Mainali, K. and Kadavelugu, A. and Hazra, S. and Bhattacharya, Subhashish and Hatua, K.}, year={2014}, pages={1626–1633} }
 @inproceedings{madhusoodhanan_patel_bhattacharya_carr_wang_2013, title={Protection of a transformerless intelligent power substation}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84899427434&partnerID=MN8TOARS}, DOI={10.1109/pedg.2013.6785610}, abstractNote={The Transformerless Intelligent Power Substation (TIPS) is being developed as an alternative to the conventional line frequency transformers at the 13.8 kV distribution grid - 480 V utility grid interface. The Front End Converter (FEC) of TIPS is composed of newly developed 15 kV/20 A Silicon Carbide (SiC) IGBTs and series connected 10 kV/10 A SiC Junction Barrier Schottky (JBS) diodes. The low device current ratings open up a big challenge in the protection of these devices in the event of faults on the a.c side or on the d.c bus as well as during high surge voltage on the line. This paper covers a detailed study of the various components of the fault protection system in terms of their breaking time, breaking current and fault coordination. The evaluation is also done with respect to different fault types like 3-phase to ground fault and single phase to ground fault at various points of the system. The effect of fault on passive elements is also considered.}, booktitle={2013 4th IEEE International Symposium on Power Electronics for Distributed Generation Systems, PEDG 2013 - Conference Proceedings}, author={Madhusoodhanan, S. and Patel, D. and Bhattacharya, Subhashish and Carr, J.A. and Wang, Z.}, year={2013} }