Mohammad Saleh Khan
Prime Minister's Research Fellow
Department of Electrical Engineering
Indian Institute of Technology Delhi
Prime Minister's Research Fellow
Department of Electrical Engineering
Indian Institute of Technology Delhi
Welcome!
I am Mohammad Saleh Khan, a research scholar at the Department of Electrical Engineering, Indian Institute of Technology Delhi.
I work in the area of power electronics. My research interests include: electric vehicle (EV) powertrain development, high gain dc-dc converters, three-phase unfolding based converters, high efficiency converters using wide band gap semiconductors.
An alternative to conventional two-stage dc to three-phase ac conversion using bidirectional boost + voltage source inverter (VSI).
The high-frequency dc-dc stage produces two series connected piecewise sinusoidal varying dc-link voltages.
The three-level unfolder stage unfolds the dc-link voltages into three-phase ac voltages, switching at fundamental frequency.
Switching losses of the inverter stage are eliminated and soft dc-link requires lower dc-link capacitance.
Measured efficiencies of 5 kW, 600 V setup above 97% for most of the speed-torque region, with peak efficiencies of 98.4%.
Highly sinusoidal output (voltage THD<2%) eliminates high dV/dt in inverter output and common-mode voltage, reducing bearing currents and motor terminal overvoltages due to wave reflections.
An alternative to non-inverting buck-boost (NIBB) converter for high-power high dc voltage applications.
Input-parallel output-series connection of NIBB and boost converter modules without requiring an isolation transformer.
Three operating modes:
Voltage step-down operation: NIBB module in buck mode, boost module in pass-through mode (disabled).
Low-gain voltage step-up operation: NIBB module in boost mode, boost module in pass-through mode.
High-gain voltage step-up operation: Both modules in boost mode.
Compared to conventional NIBB converter, proposed topology achieves higher voltage gain due to the output series connection, better switch utilization despite more number of switches, lower filter energy ratings due to ripple cancellation, and better efficiency in case of low- and high-gain boost operation.