Risikoverhalten von Aktienfondsmanagern Eine spieltheoretische und e
Unter Verwendung der Turniertheorie untersucht Peter Delling die Risikostrategie von miteinander im Wettbewerb stehenden Fondsmanagern. Die spieltheoretische Analyse geht insbesondere auf die Hypothese ein, dass Fondsmanager mit schlechter Performance zum
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In Chapter 7 we have restricted our discussion mainly on the generation of reference currents. We have assumed that the shunt compensator, which tracks the reference currents, is represented by three ideal current sources. In practice however these current sources are implemented using voltage source inverters. The inverter circuit along with interface transformers/inductors is called a distribution static compensator (DST ATCOM). In our discussions in Chapter 7 we have seen that a DST ATCOM may have to inject a set of three unbalanced currents that may also contain harmonics. Therefore, the VSI associated with a DST ATCOM must be able to inject currents in one phase independent of the other two phases. From this point of view the structure of a DSTATCOM attains significance. A DST ATCOM operating as a current source has been termed as DST ATeOM in current control mode in Chapter 4. Furthermore in Chapter 7 we have assumed that the load is connected to a stiff voltage source. Therefore the shunt compensator can measure the PCC voltages and use them in the reference current generation algorithms without any problem as these voltages are pure sinusoids. This however may not be possible in actual systems where the loads are connected at the end of the feeder. The pee voltage in this case will be unbalanced if the load is unbalanced. In addition, the PCC voltage will be distorted by both the harmonics generated by a nonlinearity in the load and by the switching frequency harmonics generated by the DST ATCOM. Furthermore there will be switching and resistive losses in the DST ATeOM circuit. These losses must be supplied by the source. We must therefore suitably modify the reference current generation algorithm to accommodate all these factors. Finally, to provide a path for the harmonic current generated by the VSI realizing the DST ATeOM to flow, we must place additional filters in the A. Ghosh et al., Power Quality Enhancement Using Custom Power Devices © Kluwer Academic Publishers 2002
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circuit. The presence of the filer and feeder impedances will then increase the system order. As we have seen in Chapter 5 that a simple output feedback switching controller may result in an unstable closed-loop system when applied to higher order systems. We must" therefore choose the OSTATCOM controller structure carefully such that the closed-loop control convergence is guaranteed. The OSTA TCOM is a shunt device. It should therefore be able to regulate the voltage of a bus to which it is connected. The operating principle of a OSTATCOM in this mode has been termed as the OSTATCOM in voltage control mode. We shall show in this chapter that even though the structure of DSTATCOM used in both current control and voltage control modes is the same, its operating principle is different. In the current control mode it is required to follow a set of refeFence currents while in the voltage control mode it is required to follow a set of reference voltages. We shall also discuss the reference voltage generation scheme and the
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