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STATCOM is a FACTS controller that is used in power systems to regulate the line voltage, enhance the power transmission capacity and extend the transient stability margin. STATCOM is conventionally realized by a voltage-source converter; however, being a current injection device, its performance can be improved when realized by a current-source converter (CSC) that can generate a controllable current directly at its output terminals. In this paper, a STATCOM based on the current-source converter topology is proposed. The nonlinear model of the current-source converter, which is the source of the difficulties in the controller design, has been modified to a linear model through a novel modeling technique. The proposed modeling technique is not based on the linearization of a set of nonlinear equations around an operating point. Instead, the power balance equation and a nonlinear input transformation are used to derive a linear model independent of the operating point. This model acts as the basis for the design of a decoupled state-feedback controller. The proposed STATCOM has been simulated using the PSCAD/EMTDC package. The simulation results show that a CSC-based STATCOM can result in excellent current and voltage waveforms as well as very short response time while operating at a low switching frequency. This makes the proposed scheme suitable for high power applications. Index Terms--CSC, decoupled state-feedback control, FACTS, linear model, STATCOM, VSC.

This paper presents modeling guidelines and a benchmark system for power system simulation studies of grid-connected, three-phase, single-stage Photovoltaic (PV) systems that employ a voltage-sourced converter (VSC) as the power processor. The objective of this work is to introduce the main components, operation/protection modes, and control layers/schemes of medium- and high-power PV systems, to assist power engineers in developing circuit-based simulation models for impact assessment studies, analysis, and identification of potential issues with respect to the grid integration of PV systems. Parameter selection, control tuning, and design guidelines are also briefly discussed. The usefulness of the benchmark system is demonstrated through a fairly comprehensive set of test cases, conducted in the PSCAD/EMTDC software environment. However, the models and techniques presented in this paper are independent of any specific circuit simulation software package. Also, they may not fully conform to the methods exercised by all manufacturers, due to the proprietary nature of the industry. [ABSTRACT FROM AUTHOR]

Advanced transportation technologies, such as hybrid-electric, battery-electric, and hybrid-fuel-cell vehicles, rely on high-power dc/dc converters to interconnect and manage their power sources. Boost converters are particularly useful in stepping up the voltage from a battery or fuel cell to match the traction motor operating voltage range. High-frequency high-efficiency operation is crucial so that the sizes of the passive components can be reduced and fuel economy can be improved. This paper proposes a new regenerative-snubber circuit that greatly reduces the switching losses of the insulated-gate bipolar transistor in the boost converter, so that high-switching-frequency operation can be achieved. The circuit uses no additional magnetic components, enjoys a simple control strategy, and results in very high efficiency while significantly reducing the mass of the converter. Two 5-kW boost converter prototypes, i.e., one with and the other without the regenerative snubber, have been built and tested to evaluate and demonstrate the impact of the proposed snubber circuit. [ABSTRACT FROM AUTHOR]

Abstract: Unified power flow controller (UPFC) and interline power flow controller (IPFC) are FACTS devices that can control the power flow in transmission lines by injecting active and reactive voltage components in series with the lines, using power converter modules, based on an externally regulated dc-link voltage. One key issue, in this application, is to find a relationship between the injected voltage and the resulting power flow in the line. In this paper, this relationship is derived analytically, and used to design two power flow control schemes. The proposed control schemes are applicable to any series-connected FACTS controller with the capability of producing a controllable voltage. In this paper, the proposed power flow control schemes are applied to a voltage-sourced converter-based IPFC, and the resulting control performances are examined using PSCAD/EMTDC simulation package. The simulation results show the effectiveness of the proposed power flow control schemes. [Copyright &y& Elsevier]

STATCOM is a FACTS controller that is used in power systems to regulate the line voltage, enhance the power transmission capacity and extend the transient stability margin. STATCOM is conventionally realized by a voltage-source converter; however, being a current injection device, its performance can be improved when realized by a current-source converter (CSC) that can generate a controllable current directly at its output terminals. In this paper, a STATCOM based on the current-source converter topology is proposed. The nonlinear model of the current-source converter, which is the source of the difficulties in the controller design, has been modified to a linear model through a novel modeling technique. The proposed modeling technique is not based on the linearization of a set of nonlinear equations around an operating point. Instead, the power balance equation and a nonlinear input transformation are used to derive a linear model independent of the operating point. This model acts as the basis for the design of a decoupled state-feedback controller. The proposed STATCOM has been simulated using the PSCAD/EMTDC package. The simulation results show that a CSC-based STATCOM can result in excellent current and voltage waveforms as well as very short response time while operating at a low switching frequency. This makes the proposed scheme suitable for high power applications. [ABSTRACT FROM PUBLISHER]

Presents a study that proposed a direct alternating current (ac)/ac converter topology based on current-source converter modules. Structure of the proposed ac/ac converter topology; Principles of operation of the proposed ac/ac converter topology; Available control levers.

Proposes a modular approach to active harmonic filtering which is conventionally performed by injecting equal-but-opposite of the distortion into the line. Rating of the power converter used for the purpose on the magnitude of the distortion current and operated at switching frequency dictated by the desired bandwidth; Linear adaptive neurons used by the method.

Proposes a multi-converter active power-line filter based on current-source converter (CSC) modules. Performance of active power filtering by detecting the line current and voltage signals; Power rating and switching frequency of each CSC module; Utilization of two linear adaptive neurons to process the signals obtained from the line.

Presents information concerning the voltage-source matrix converter. Capacity of the converter; Effects of the series reactance compensation; Originality of this matrix converter.