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An Isolated Topology for Reactive Power
Compensation With a Modularized DynamicCurrent Building-Block
Abstract:
This paper presents a novel topology for instantaneous reactive power
compensation. The topology is derived from Dynamic-Current or Dyna-C, which
is a patented power converter capable of transferring energy for two- or multiterminal DC, single- and/or multi-phase AC systems. The proposed topology has a
modularized low-voltage current source building block that can be stacked for
medium-voltage (MV) applications to provide dynamic leading or lagging reactive
power. In addition, the phases are coupled through a high-frequency transformer
for inter-phase fault isolation among the three-phase. The converter functionality is
validated through simulations and experimental results with a 480
V, 75 kVAr prototype.
Existing system:
 Proliferation of non-resistive loads imposes power quality concerns over the
existing grid network. The reactive power loads, which possess a low power
factor, draw high amount of volt-ampere reactive power from the grid and
thus restrict the active power transfer capability.
 The excessive reactive power flow over the network heavily burdens the
transformer, distribution and transmission lines, increases the line losses,
and impacts the voltage stability.
Proposed system:
 The proposed system proposes a novel modular current source inverter (CSI)
based topology to provide STATCOM functionality. The topology is derived
from Dynamic-Current or Dyna-C, a patented power converter capable of
transferring energy for two- or multi-terminal DC, single- and/or multiphase AC systems.
 The topology, named Dynamic VAr Compensator (DVC), employs a highfrequency transformer rather than a DC capacitor as the means to store
energy, which limits the maximum current that can contribute to a fault. The
paper presents the topology and the operating principles, and validates the
core functionality through simulation results and experimental
measurements of a 480 V / 75 kVAr prototype.
Circuit diagram:
Reference: