India
Developed, Implemented IGBT based 50 kVA Active Power Factor Correction (APFC) and validated by installing it in the company itself, gives 0.99 PF in the subsequent monthly power supply bill. Worked in improving the system performances of various ratings of IGBT dc-dc converters / Thyristor based converters by choosing appropriate filters on ac side and dc side, and suitable snubber circuits making them reliable, cost effective with good quality, and tested to meet the standards as per customer requirements. Worked on building the modules of 50 kVA APFC and 30 kVA battery charger with suitable components choice and improvement in assembly for building 100 kVA eV battery charger stations for cars and trucks. Simulation of various ratings of thyristor-based converters for identifying the input ac current harmonic content and the power factor for wide range of loading conditions. To choose ac filter and capacitor requirements are identified to minimize the harmonics and to improve the power factor as well. Improvements done in TMS320F28069 based controller PCB by including circuits for over voltage, overcurrent protections that either occur in grid side or load side.
Current Source Inverter (CSI) based interfacing low voltage PV panel to 400 V grid in single stage. The power from PV panel is extracted at MPP (Incremental conductance MPPT) and pumped into the grid. Proposed a novel Translated Space Vector PWM helps in simplifying the control algorithm in dq synchronous frame and results in good dynamic response. Cascaded CSC + CSI fed induction motor drive is developed for sub-sea mining applications in IIT Madras, sponsored by NIOT, Chennai. FOC algorithm is developed in dq frame for attaining good dynamic response as well as to limit the harmonic current drawn from the mains. Developed MATLAB based GUI for analyzing a huge data base of Grid data recorded for years using power quality analyzers from industrial, commercial and domestic locations. Helps in easy walk through the data for gathering key information like sag, swell, THDs, sudden spikes and dips, +ve, -ve, zero sequence components of voltage and current signals occurred at different occasions. For understanding the sources of such events and to take appropriate actions (Part of Danfoss funded project in IIT Madras). Mathematical modeling of Power Electronics and Drives based systems and evaluation of them in MATLAB/ Simulink, LTspice, PSpice. Magnetics design and FEA analysis of High frequency Transformers, filter inductor for dc dc converters S. Saravanan and Krishna Vasudevan,” A novel CSI based approach for grid integrated PV system,” in IEEE International Conference on Power Electronics, Drives and Energy Systems (PEDES). 2016, pp.1-6. S. Saravanan and Krishna Vasudevan,” Comparative Evaluation of Current Source Inverters Interfacing Photo - Voltaic system to Grid for Modified Space Vector PWM Techniques,” in IEEE proceedings 40th PVSC, 2014, pp. 3129-3133. Gurusrinivas Nainar, S Saravanan, P Kunathi, K. Hatua, K. Vasudevan, “Pulse Width Modulated CSI fed Induction Motor Drive for Sub-sea Mining Application,” in Conference Proceedings of IISc, 2015.