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This paper presents a novel topology for instantaneous reactive power compensation. The topology is derived from the Dynamic-Current or Dyna-C, which is a patented power converter capable of transferring energy for two or multiterminal dc, single- and/or multiphase ac systems. The proposed topology, named dynamic VAr compensator (DVC), has a current source power conversion stage and can provide instantaneous leading or lagging reactive power. The proposed DVC has three individual bridges coupled through a three-winding high-frequency transformer. It has a modular structure that allows it to be series stacked for medium-voltage applications. In addition, the high-frequency Galvanic isolation link provides interphase fault isolation among the three phases. The circuit eliminates the use of electrolytic capacitors for bulk energy storage, which usually lowers life and reliability. Operating principles, theoretical analysis, and design of the proposed topology are described. The converter functionality is validated through simulation as well as experimental results. [ABSTRACT FROM AUTHOR]

This paper presents a topology for bidirectional solid-state transformers with a minimal device count. The topology, referenced as dynamic-current or Dyna-C, has two current-source inverter stages with a high-frequency galvanic isolation, requiring 12 switches for four-quadrant three-phase ac/ac power conversion. The topology has voltage step-up/down capability, and the input and output can have arbitrary power factors and frequencies. Further, the Dyna-C can be configured as isolated power converters for single- or multiterminal dc, and single- or multiphase ac systems. The modular nature of the Dyna-C lends itself to be connected in series and/or parallel for high-voltage high-power applications. The proposed converter topology can find a broad range of applications such as isolated battery chargers, uninterruptible power supplies, renewable energy integration, smart grid, and power conversion for space-critical applications including aviation, locomotives, and ships. This paper outlines various configurations of the Dyna-C, as well as the relative operation and controls. The converter functionality is validated through simulations and experimental measurements of a 50-kVA prototype. [ABSTRACT FROM PUBLISHER]

The Dynamic Current or Dyna-C is a minimal topology for implementing the bidirectional three-phase solid-state transformer (SST). While only two current-source power conversion stages are employed, the Dyna-C SST has features of voltage step up/down, arbitrary power factors, and frequencies between the input and output terminals. In this paper, a compact 50-kVA three-phase SST based on this minimal topology is designed. More specifically, design considerations and practical implementation techniques are presented. Results from experimental measurements are shown and discussed. [ABSTRACT FROM AUTHOR]

Industrial plants are faced with stringent requirements enforced by the utility to meet power factor and power quality requirements. These plants, in order to avoid very costly penalties, have traditionally utilized switchable shunt capacitor banks with detuning reactors for power factor correction, along with a separate active harmonic filter in cases where harmonic currents are an issue as well. Alternate solutions such as SVCs and STATCOMs have been considered to be too expensive for use in industrial power conditioning applications. This paper proposes a dynamic capacitor (D-CAP) based on the family of inverter-less active filters that is able to provide a dynamically controllable capacitance with active harmonic filtering integrated into the same unit. This new device is seen to be compact, and is likely to be cost competitive against simple switched shunt capacitors. It can maintain power factor close to unity, offering dynamic capabilities better than switched capacitors or SVCs, possibly lending itself for arc-furnace type of loads. [ABSTRACT FROM PUBLISHER]