@article{isik_burugula_alharbi_azidehak_bhattacharya_2022, title={Implementation of a Modular Distributed Fault-Tolerant Controller for MMC Applications}, volume={15}, ISSN={["1996-1073"]}, DOI={10.3390/en15228427}, abstractNote={Centralized control algorithm limits the hardware flexibility of a modular multilevel converter (MMC). Therefore, distributed control structure has recently started to be seen in the industry application. Even though distributed controller reduces a single point of failure risk compared to the centralized controller, the failure risk of the entire control systems increases due to the number of local controllers. However, the distributed controller can be programmed in such a way as to replace the faulty local controller and sustain the MMC operation. In this paper, the distributed modular fault-tolerant controller is implemented in a laboratory-scale MMC prototype. The controller is built to control four SMs per phase for the proof-of-concept. Therefore, the MMC prototype is also built by two SMs per arm. The controller capability is validated with experimental and the Opal-RT result-time simulator results in a control-hardware-in-loop (CHIL) environment.}, number={22}, journal={ENERGIES}, author={Isik, Semih and Burugula, Vasishta and Alharbi, Mohammed and Azidehak, Ali and Bhattacharya, Subhashish}, year={2022}, month={Nov} }
 @inproceedings{azidehak_hwang_agarwal_bhattacharya_yousefpoor_2017, title={Fault-tolerant controller architecture for cascaded multi-level converters}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85019991207&partnerID=MN8TOARS}, DOI={10.1109/apec.2017.7931086}, abstractNote={Voltage source multi-level converters (MC) are one of the options for rectifying and inverting in high power applications. Each converter consists of several modules connected together to form a single converter. Power rating of the converter is usually more than the desired rating and it is possible to continue operation by bypassing the failed modules. This capability increases the reliability of this category of converters compared to other type of converters. In this paper, a distributed controller has been proposed that implements hot standby techniques to increase reliability and availability of the converter. Each slave controller is directly connected to the power electronic module with data link to neighbor controllers and all of the controllers are being synchronized through a master controller. At the end, reliability assessment of the proposed controller based on Markov modeling has been represented and experimental result approves the feasibility of the control method.}, booktitle={Conference Proceedings - IEEE Applied Power Electronics Conference and Exposition - APEC}, author={Azidehak, A. and Hwang, M. and Agarwal, R. and Bhattacharya, Subhashish and Yousefpoor, N.}, year={2017}, pages={2738–2744} }
 @article{yousefpoor_parkhideh_azidehak_kim_bhattacharya_2015, title={Control of High-Frequency Isolated Modular Converter}, volume={51}, ISSN={["1939-9367"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84957878360&partnerID=MN8TOARS}, DOI={10.1109/tia.2015.2457402}, abstractNote={Recently, voltage-source converter (VSC)-based high-voltage dc (HVDC) transmission systems have gained more attention. In this paper, a control method for a modular VSC-based HVDC transmission system with high-frequency isolation referred to as high-frequency isolated modular converter is proposed. In the high-frequency isolated modular converter configuration, several floating dc capacitors in all three phases are connected in series, and voltage balancing control of these floating dc capacitors is required. In this paper, an appropriate control structure with the capacitor voltage balancing controller is proposed. The proposed control scheme consists of three layers to control terminal dc bus voltage and balance dc capacitor voltages of each building block. Detailed PSCAD simulation results are presented to evaluate the performance of high-frequency isolated modular converter. Controller hardware-in-the-loop simulation of the high-frequency isolated modular converter is also performed by real-time digital simulator (RTDS), and RTDS results are presented to verify the control structure. Finally, laboratory-scale experimental results are presented to validate the proposed control method.}, number={6}, journal={IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS}, author={Yousefpoor, Nima and Parkhideh, Babak and Azidehak, Ali and Kim, Sungmin and Bhattacharya, Subhashish}, year={2015}, pages={4634–4641} }
 @inproceedings{azidehak_chattopadhyay_acharya_tripathi_kashani_chavan_bhattacharya_2015, title={Control of modular dual active bridge DC/DC converter for photovoltaic integration}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84963537568&partnerID=MN8TOARS}, DOI={10.1109/ecce.2015.7310140}, abstractNote={The DC transmission system provides a cost effective solution for long distance power transmission compared to the AC transmission system. Hence, this has increased the emphasis on the development of the DC transmission system. Development of power converter with modular structure has now made it possible to achieve higher voltage and power level. This opens the possibility for further development of a multi-terminal DC grid. Now once the DC grid system has been formed, it is also important to include more renewable energy sources directly to the DC grid. Therefore, a power conversion stage is required to condition the available power from a source to the grid. This paper shows the operation and control of such a kind of converter system which integrates the solar cell to the DC grid directly. The paper mainly focuses on control of the series connected DAB that have been integrated to HVDC power network. In order to deliver power in HVDC system, the total number of DABs must be high enough to achieve the DC link voltage. The control in that case must be a combination of current and voltage control. In order to validate the proposed control, complete system has been implemented on Opal-RT™ and hardware in the loop (HIL) using external controller has also been implemented to show the system operation.}, booktitle={2015 ieee energy conversion congress and exposition (ecce)}, author={Azidehak, A. and Chattopadhyay, R. and Acharya, Sayan and Tripathi, A. K. and Kashani, M. G. and Chavan, G. and Bhattacharya, S.}, year={2015}, pages={3400–3406} }
 @inproceedings{acharya_azidehak_vechalapu_kashani_chavan_bhattacharya_yousefpoor_2015, title={Operation of hybrid multi-terminal DC system under normal and DC fault operating conditions}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84963585191&partnerID=MN8TOARS}, DOI={10.1109/ecce.2015.7310417}, abstractNote={Recently, multi-terminal DC (MTDC) system has received more attention in the power transmission areas. Development of modular structured power converter topologies has now enabled the power converter technology to attain high voltage high power ratings. Compared to current source converter technology, voltage source converters have several benefits including higher power quality, independent control of active and reactive power etc. This paper focuses on a unique MTDC system consisting of terminals with different converter topologies especially considering the fact that each of the terminals may be manufactured by different vendors. In this particular configuration, the MTDC system consists of four terminals namely two advanced modular multi-level converter with high frequency isolation, one standard modular multi-level converter (MMC) with half bridge sub modules and the fourth terminal is modular DC-DC converter which integrates PV along with a Battery energy storage system with the DC grid directly. This paper presents a system level study of hybrid MTDC System. Also the DC fault contingency case has been explored thoroughly. An algorithm has been proposed to prevent the system damage. All the cases have been demonstrated with the PSCAD simulation results. To show the system practically works in real time, the system is also evaluated in a unique real time platform, consisting of interconnected RTDS and OPAL RT systems.}, booktitle={2015 ieee energy conversion congress and exposition (ecce)}, author={Acharya, Sayan and Azidehak, A. and Vechalapu, K. and Kashani, M. and Chavan, G. and Bhattacharya, S. and Yousefpoor, N.}, year={2015}, pages={5386–5393} }
 @article{yousefpoor_parkhideh_azidehak_bhattacharya_fardanesh_2014, title={Modular transformer converter-based convertible static transmission controller for transmission grid management}, volume={29}, number={12}, journal={IEEE Transactions on Power Electronics}, author={Yousefpoor, N. and Parkhideh, B. and Azidehak, A. and Bhattacharya, S. and Fardanesh, B.}, year={2014}, pages={6293–6306} }
 @inproceedings{yousefpoor_azidehak_bhattacharya_parkhideh_2013, title={Control of active mobile substations under system faults}, booktitle={2013 ieee energy conversion congress and exposition (ecce)}, author={Yousefpoor, N. and Azidehak, A. and Bhattacharya, S. and Parkhideh, B.}, year={2013}, pages={1968–1975} }
 @inproceedings{yousefpoor_azidehak_bhattacharya_parkhideh_2013, title={Experimental validation of modular transformer converter based convertible static transmission controller for transmission grid management}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84891109040&partnerID=MN8TOARS}, DOI={10.1109/ecce.2013.6647036}, abstractNote={For power flow control with specific attention to renewable energy resources based transmission in a meshed network, less complex coordinated control can be obtained with the proposed Convertible Static Transmission Controller (CSTC) concept which is connected across the substation power transformer and can be reconfigured to the required modes of operation. Convertible Static Transmission Controller (CSTC) is a versatile transmission controller which can perform several functions including power flow control for renewable resources transmission and transformer back-up for disaster management or life extension purposes. Different connecting configuration options (shunt-shunt, series-shunt, and series-series) can be obtained in the proposed transmission controller. In this paper, the control structure of CSTC in different modes of operation is presented, and dynamic performance of the CSTC based on the proposed control structures is further investigated in three different connecting configurations in PSCAD/EMTDC environment. Lab-scale experimental results are also presented to evaluate the performance of CSTC in three different modes of operation.}, booktitle={2013 IEEE Energy Conversion Congress and Exposition, ECCE 2013}, author={Yousefpoor, N. and Azidehak, A. and Bhattacharya, Subhashish and Parkhideh, B.}, year={2013}, pages={2597–2604} }
 @inproceedings{yousefpoor_azidehak_bhattacharya_parkhideh_celanovic_genic_2013, title={Real-time Hardware-in-the-Loop simulation of convertible static transmission controller for transmission grid management}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84889049526&partnerID=MN8TOARS}, DOI={10.1109/compel.2013.6626403}, abstractNote={We propose a Convertible Static Transmission Controller (CSTC) concept that enables coordinated power flow control with emphasis on large penetration of renewable energy resources based transmission in a meshed network. CSTS can be connected across the substation power transformer and reconfigured for different modes of operation to perform as a versatile transmission controller with several functions including: power flow control for transmission of renewable resources, and as a transformer back-up for disaster management and/or life extension purposes. Different connecting configuration options, i.e. shunt-shunt, series-shunt, and series-series can be obtained. In this paper, we demonstrated the viability of the proposed concept using Typhoon HIL400 ultra-high fidelity Hardware-in-the-Loop (HIL) system in three different modes of operation. HIL simulations are used to verify the validity of the proposed control architecture for CSTC operation during both normal and unbalanced power system conditions for different connecting configurations.}, booktitle={2013 IEEE 14th Workshop on Control and Modeling for Power Electronics, COMPEL 2013}, author={Yousefpoor, N. and Azidehak, A. and Bhattacharya, Subhashish and Parkhideh, B. and Celanovic, I. and Genic, A.}, year={2013} }