PROJECT TITLE :

Power Factor Control for High Efficiency Operation of an Open-Ended Winding Motor Using a Dual Inverter Drive with a Floating Bridge - 2017

ABSTRACT:

A completely unique control scheme is presented for an open-ended winding motor dual inverter drive, where a primary inverter is supplied from a dc power supply and a secondary inverter is supplied from a floating dc capacitor with no power source. Examination of the fundamental single phase equivalent circuit model of an induction machine reveals that close to optimal motor potency is achieved at a comparatively constant motor basic power factor over a wide selection of motor masses and drive operating frequencies, e.g. 0.seventy one for the motor utilized in this work. The drive management described uses the part distinction between the fundamental output voltages of the first and secondary converters so as to manage the motor's terminal voltage and to take care of a motor power issue of zero.seventy one. This management is maintained over the complete range of the motor's load and drive frequency settings. The floating capacitor bridge voltage is regulated using PI feedback control, with the capacitor voltage error signal as the input and also the amplitude modulation index of the first inverter as the output. The capacitor voltage reference signal is connected to the per-unit drive frequency and measured current: because the motor's current or frequency changes, the capacitor's voltage reference is updated in a very proportional manner to each parameters. This management approach keeps the basic phase difference between the two inverters within a stable operating vary, maintains the facility issue of the most bridge close to unity, and improves the floating bridge's dc capacitor voltage stability throughout transient load changes. The drive management performance is presented using detailed simulations and experimental testing; verifying the regulation of the floating capacitor's voltage in addition to the expected potency gains for the induction motor beneath constant power factor operation as compared with conventional drive control.