Design And Control of Medium Voltage Induction Motor Drive With Improved Power Quality

The exploration of power converters for industrial drive applications reveals that these converters not only give harmful impacts on instruments connected at the grid end but are also harmful to the motor. Hence, enhancement of power quality using advanced power converters (multi-pulse AC-DC and multilevel DC-AC) units is investigated in this paper. To attain this, a multiphase and phase displacement techniques-based rectification system is designed and developed to achieve the IEEE-519 power quality standard at the grid end of the drive system. The presented technique (multiphase and phase displacement) is adopted to develop a fifty-pulse AC-DC converter system from the joint connection of five isolated multi-winding transformers (T
1
, T
2
, T
3
, T
4
, T
5
), where each transformer is designed in such a manner so that it converts three phase AC supply to five phase AC supply. Apart from this, in recent years the interest in multilevel DC-AC converters for medium voltage and reliable drives is growing. Focused on this, a six-level cascaded multilevel inverter is designed and developed, which delivers power to a medium voltage induction motor as per international standard of power quality IEEE-519. The rigorous design of a fifty-pulse AC-DC converter and the response analysis of the drive system under various operating conditions are made. The appropriateness of the system is verified by simulated results conducted on a 2.7MW (3620hp), 6.6kV induction motor on the MATLAB/Simulink platform.