SMART POWER CONVERSION SYSTEM

CASCADED MULTILEVEL INVERTER BASED ON TRANSISTOR-CLAMPED H-BRIDGE POWERCELL

The cascaded multilevel inverter uses 5-level transistor-clamped   H-bridge (TCHB) power cell.Two-cell configuration can produce up to 17 levels of line voltage, sufficient to produce a high-quality output.Total power loss is lower compared to other conventional cascaded multilevel inverters (i.e. cascaded NPC and 9-level CHB) that produce the same output quality at the same operating voltage owing to lower component counts.

The inverter is potential for use in medium-voltage applications (e.g. electric drives in heavy industries, ship propulsion, electric train as well as flexible ac transmission system (FACTS) devices – STATCOM, DVR,  etc.).

MODIFIED THREE-PHASE AC/DC CONVERTER WITH CASCADED BOOST-SEPIC OUTPUT STAGE

A modified three-phase buck rectifier with cascaded boost-SEPIC converter at the output stage operates in continuous-conduction mode (CCM), and its purpose is to achieve sinusoidal input currents with low current total harmonic distortion (THD), near-unity power factor, and high DC voltage gain during low duty cycle operation. Altera field-programmable gate array (FPGA) is used to generate pulse-width modulated (PWM) control signals, and to compute  Proportional-Integral-Derivative (PID) algorithm.

MOTOR AND DRIVES

SENSORLESS VECTOR CONTROL DRIVES FOR INTERIOR PERMANENT MAGNET SYNCHRONOUS MOTOR BASED ON SIMPLIFIED STATOR FLUX OBSERVER

This research focuses on the implementation of sensorless closed-loop field oriented control (FOC) drives system using simplified stator flux observer (SFO) in TMS320F2812 digital signal processor (DSP) platform. The overall performance of the drive system is observed and tested using a 600W, 4 poles IPMSM at different speed reference, constant load condition.

SMART TRANSPORTATION SYSTEM

OPERATION OF A SIX-PHASE INDUCTION MACHINE WITH SERIES-CONNECTED CONVERTERS

Compared with conventional parallel-connection, the topology with series-connected converter provides the following advantages:

• Possibility of operating low voltage machine at higher dc-link voltage  without need for voltage boosting stage
•  Reduction in dc-link current rating and cable size.
• Possibility of operating with reduced CMV, which reduces leakage current that can damage the machine.

AUTOMATION AND CONTROL

DISTRIBUTED COLLISION AVOIDANCE ALGORITHMS FOR AUTONOMOUS UNMANNED AIRCRAFT

Novel distributed CAS algorithms have been proposed supporting UAV free-flight concept. This work focused on CAS development and verification. Avoidance is formulated by finding the optimal control commands that minimize multi-level cost functions, considering UAV safety & trajectory deviation efficiency. Experiments conducted conclude that the proposed CAS guarantees safety, operates in real-time and is efficient in terms of flight-path length deviation.