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A High Voltage Large Capacity Dynamic Var Compensator Using Multilevel Voltage Source Inverter
| Content Provider | Semantic Scholar |
|---|---|
| Author | Choi, Natn S. Dong, Kusong Gu, Yingling |
| Copyright Year | 2004 |
| Abstract | A multilevel PWM voltage source inverter, especially jive-level one, is introduced to a static Var compensatorfSVC) as a large scale power source. The SVC can be directly connected to QC mains of 6600 volts allowing full utilization of semiconductor devices like GTOs. The voltage balancing condition of the DC side capacitors is pointed out based on the fundamental circuit modeling of the inverter and a five-level PWM is employed to meet the condition. Owing to multilevel approach, a low distortion in the input currents results and thus, filter size is minimized. I. INI'RODUCTION It is well known that a voltage source inverter(VS1) can be used as a static Var compensator(SVC) supplying fundamental reactive power. Capability of controlling the magnitude and phase as well as frequency of the output voltage in VSI provides continuous variation of leading or lagging reactive power supplied to the ac mains. In addition, the SVC has not only less and smaller reactive components which may result in smaller size, weight and cost but also some possibility of eliminating or suppressing harmonic components in the ac mains [1][2][3]. For a large scale Var compensation, however, high powerhigh voltage VSIs have their limitations to handle high powerhigh voltage and to operate at high switching frequency due to lack of h g h power self commutated semiconductor switches with high switching frequency characteristics (>lkHz). Moreover, various PWM switching strateges are no longer applicable to such large scale SVC systems. Hence, the high powerhigh voltage VSI is indispensable to large scale SVC system and we can say that the structure of the inverter primarily affects the system performance along with several control schemes [ 1][2]. So far, conventional high power VSIs should be made up of either problematic seriedparallel switch combinations or several small inverter combinations. Of them, multiple inverter systems with coupling components such as transformers have been accepted as a reasonalble solution to cope with such high power applications, which makes it possible to utilize the switching devices at hand relatively easily. In addition, the multiple inverter system provides multilevel output voltages and thus it is also preferred in the context of harmonic reduction. But to prevent excessive harmonic current injection into the network, either a number of inverter stages or several harmonic filter legs should be employed and thus such an SVC system becomes expensive, |
| File Format | PDF HTM / HTML |
| Alternate Webpage(s) | http://koasas.kaist.ac.kr/bitstream/10203/6565/1/%5B1992%5DA%20High%20Voltage%20Large%20Capacity%20Dynamic%20var%20Compensator%20Using%20Multilevel%20Voltage%20Source%20Inverter.pdf |
| Language | English |
| Access Restriction | Open |
| Subject Keyword | Clock rate Distortion Electric Power Supplies Equilibrium Inverter Device Component Jive Network switch Pokeweed Mitogens Power inverter Providing (action) Pulse-width modulation Semiconductor device Small Switch Device Component Transformers Volt Voltage source g/h |
| Content Type | Text |
| Resource Type | Article |
