IZBOR POGONSKOG PODSISTEMA ELEKTRIČNOG VOZILA SA NAGLASKOM NA MAŠINE SPECIJALNE KONSTRUKCIJE

U modernom dobu inovativna rešenja nude različite izvore energije koji mogu pokretati vozila. Još u 19. veku, naučnici su spoznali značaj električnih vozila, ali u pokušaju da ih tada distribuiraju na tržište nisu uspeli. Danas, sa napretkom tehnologije moguća je globalna upotreba električnih vozila. U ovom radu analizirana su električna vozila sa naglaskom na njihov električni pogonski podsistem. Kao idejno rešenje, odabrana je električna pogonska mašina specijalne konstrukcije, Brushless DC mašina koja bi mogla zadovoljiti potrebe vozila sa električnim pogonom.&#x0D;  </jats:p

Control Strategy for a Grid Connected Converter in Active Unbalanced Distribution Systems

The development in distributed energy resources technology has led to a significant amount of non-linear power electronics converters to be integrated in the power system. Although this leads to a more sustainable system, it also can have adverse impacts on system stability and energy power quality. More importantly, the majority of the distribution power systems currently are unbalanced (with asymmetrical voltages) due to load unbalance, while the most common fault types are unbalanced grid faults that can have many adverse effects on distributed resource operations. In that regard, proper control of the grid connected converters in active unbalanced distribution systems will become very important. This paper aims to present the behavior of the advanced grid connected converter control technique under different voltage states at the point of common coupling (according to the ABC classification). The main insufficiencies of the classical control technique will be highlighted, while the paper will propose an appropriate solution for mitigation of negative sequence currents under asymmetrical voltages at the point of common coupling. An extensive experimental verification of the proposed techniques is performed using an advanced laboratory prototype for research in grid integration of distributed resources. The experimental verification clearly demonstrates the benefits offered by the advanced control strategy.</jats:p

Speed-sensorless control strategy for multi-phase induction generator in wind energy conversion systems

Renewable energy sources, especially wind energy conversion systems (WECS), exhibit constant growth. Increase in power and installed capacity led to advances in WECS topologies. Multi-phase approach presents a new development direction, with several key advantages over three-phase systems. Paired with a sensorless control strategy, multi-phase machines are expected to take primacy over standard solutions. This paper presents speed sensorless vector control of an asymmetrical six-phase induction generator based on a model reference adaptive system (MRAS). Suggested topology and developed control algorithm show that sensorless control can yield appropriate dynamic characteristics for the use in WECS with increase in reliability and robustness.</jats:p

Control Strategy for a Grid Connected Converter in Active Unbalanced Distribution Systems

The development in distributed energy resources technology has led to a significant amount of non-linear power electronics converters to be integrated in the power system. Although this leads to a more sustainable system, it also can have adverse impacts on system stability and energy power quality. More importantly, the majority of the distribution power systems currently are unbalanced (with asymmetrical voltages) due to load unbalance, while the most common fault types are unbalanced grid faults that can have many adverse effects on distributed resource operations. In that regard, proper control of the grid connected converters in active unbalanced distribution systems will become very important. This paper aims to present the behavior of the advanced grid connected converter control technique under different voltage states at the point of common coupling (according to the ABC classification). The main insufficiencies of the classical control technique will be highlighted, while the paper will propose an appropriate solution for mitigation of negative sequence currents under asymmetrical voltages at the point of common coupling. An extensive experimental verification of the proposed techniques is performed using an advanced laboratory prototype for research in grid integration of distributed resources. The experimental verification clearly demonstrates the benefits offered by the advanced control strategy

Sub-Transient Response of the DSC Controlled Inverter under Fault

The most important element of the new active distribution system concept is the grid connected converter that needs to offer fault ride through capabilities. The new system topologies require new tools for fault state calculation that would consider different control methodologies. In that regard, this paper investigates the initial response of the grid connected inverter under fault that operates using new control methodology based on the integration of the delay signal cancellation. Using modern laboratory setup for testing of renewable energy sources and their integration in the power system the technique is weighed against the classical technique that does not provide the adequate control under unbalanced faults. Furthermore, through a set of specific experiments the paper demonstrates the behavior of the converter under fault, preparing the outline for the fault response modeling of distributed energy resources. Experimental results present the sub-transient period and the transient period of the response, giving the attention to the inrush current (initial peak current) of the converter. It has been shown that the new technique has similar behavior as the classical control for the balanced faults (symmetrical voltage states), while the values of the peak current for different type of unbalanced faults (asymmetrical voltages where classical technique can be proven to be ineffective) has also been demonstrated.</jats:p