G. Pranay Kumar, P. Pradyumna
In this paper, design of modular brushless dc motor drive and its operation in four quadrants is described. In this design, each permanent magnet BLDC motor is powered by an inverter and number of motors and inverter sets are stacked together in order to give the required power rating and to have good reliability. The four quadrant operation of this design is also done in this paper to operate the motor clockwise and counter clockwise i.e., in motoring mode and regenerative braking mode. This is essential in saving the power as in the regenerative braking mode of operation, the power is fed back to the supply mains. The speed control of the drive system is also studied in this paper.