Carlos A. Reusser

Full electric ship propulsion based on a flying capacitor converter and an induction motor drive

Modern ship propulsion systems are looking towards to high efficiency electric drive systems. The present paper presents the dynamic behaviour of a naval Full Electric Propulsion (F.E.P.) system based on a Flying Capacitor Multilevel Inverter and an Induction Motor Drive. Simulation results based on real hull dynamic data where carried out for load loss, load impact and speed reversion.

Dual three-phase PMSG based wind energy conversion system using 9-switch dual converter

The following work introduces the use of a nine-switch back-to-back topology, for its use with multiphase permanent magnet synchronous generator, based wind energy conversion systems (WECS). The converter topology consists of a nine-switch dual channel back-to-back three-phase voltage source converter capable of controlling two sets of three-phase variables without voltage limitations when operating both three-phase systems at same frequency. This feature is exploited to control both ends of the PMSG and both terminals of a 12 pulse transformer for grid connection.

Back-to-back wind energy conversion system configuration based on 9-switch dual converter and open-end-winding PMSG

The following work introduces the use of a dual three-phase converter with reduced number of switches in a back-to-back configuration for its application to an open-end-winding permanent magnet synchronous generator based wind energy conversion systems (WECS). The converter topology consists of a nine-switch dual three-phase voltage source converter capable of controlling two sets of three-phase variables without voltage limitations when operating both three-phase systems at same frequency. This feature is exploited to control both ends of the PMSG and the three phase inputs of a 12 pulse transformer witch connects the grid. The open-end winding generator connection provides more space vectors for control while the 12 pulse grid-connection enables mitigation of switching harmonics.

Nine switch multi-channel dual converter for WECS

The following work introduces the use of nine-switch converter in a multi-channel dual configuration for its use with multiphase permanent magnet synchronous generator, based wind energy conversion systems (WECS). The converter topology consists of a nine-switch dual channel three-phase voltage source converter capable of controlling two sets of three-phase variables without voltage limitations when operating both three-phase systems at same frequency. This feature is exploited to control both ends of the PMSG and both terminals of a 12 pulse transformer for grid connection.

Nine-switch converter application on electric ship propulsion — A redundancy approach

Currently used inverter solutions for ship propulsion applications are based in classic voltage source inverter (VSI) topologies, mostly two-level voltages source inverters (2L-VSI) and cascaded H-Bridge voltage source inverters (CHB-VSI) which have became a standard as from the industrial point of view. Nevertheless, modern ship propulsion applications are required to operate under faulty conditions, demanding power electronics to ensure redundancy capability. This work presents a redundant converter topology based on a nine-switch inverter, for its application in electric-propelled ships.

Low frequency sensorless Field Oriented Control of an induction machine fed by a direct matrix converter

The main open problem in sensorless Field Oriented Control is to achieve orientation at very low frequency due to the low back-EMF signal, affecting the capability of any observer structure to estimate flux and speed. This problem is worsen by the converter non-linearities, like voltage drop and dead-time in VSI, that become significant at low frequency. This problem restricts the sensorless operation of nay drive to medium and high frequencies. On the other hand, Matrix Converters have received increasing attention recently and their benefits are still being studied. One of this benefits is the capability to synthesize better sinusoidal voltages, having an almost linear behaviour when controlled with four step commutation. Furthermore, the small commutation error of the four step commutation strategy has been characterized in literature and can be compensated. In this paper, the low speed performance of a sensorless vector controlled Matrix Converter drive is studied experimentally and the effects of the compensation of the device voltage drop and commutation error is evaluated. The well known extended Kalman filter (EKF) structure is used as state observer.

Permanent Magnet Synchronous Generator WECS based on a four-level double star converter

The following work introduces the use of a modified four-level medium voltage converter in a back-to-back configuration for its application on wind energy conversion systems (WECS). The proposed converter topology is based on a three-level neutral-point clamped converter (3L-NPC) without clamping diods or power switches, so that dc-link capacitors are in a floating condition respect to the neutral point. The implementation of the back-to-back configuration enables the topology for its application in variable speed SM - Permanent Magnet Synchronous Generator WECS.

Medium voltage 4-level double-star multilevel converter using model predictive control

The double-star converter (DSC) is a recently introduced medium-voltage 4-level multilevel inverter topology, with a reduced number of active switches. This topology has several advantages over existing commercial topologies (single dc-source, no clamping elements, no bidirectional switches or flying capacitors), which can satisfy the needs of several medium voltage applictions such as pumps, fans and compressors. The main challenge with this topology is the voltage balance of the three dc-link capacitors across the modulation index range. Classic controllers require sophisticated PWM techniques with closed loop compensation to maintain the capacitor voltages balanced. In this paper, a control algorithm based on model predictive control (MPC) is applied to the DSC, allowing a direct regulation of the converter output currents while simultaneously ensuring the dc-link capacitors voltage balance. Simulation results show the effectiveness of MPC when applied to this converter.

Full-electric ship propulsion, based on a dual nine-switch inverter topology for dual three-phase induction motor drive

Modern ship propulsion systems are looking towards to high efficiency electric drive systems. This work presents a new inverter configuration for multiphase AC drives for its application in Full-Electric Ship (FEP) propulsion. Simulation results based on real hull dynamic data where carried out different load impacts and speed reversion in normal and stator winding faulty conditions.