Abstract – This paper presents a
Distribution Static Compensator (DSTATCOM) that uses a traditional
Synchronous Reference Frame (SRF) to make source current in phase and
sinusoidal in shape w.r.t source voltage, so that unity power factor is
achieved at source side. In addition to this, a new concept of single
phase synchronous d-q reference frame theory is used for generation of
reference signals in a three phase distribution system for compensation
of voltage unbalances at the load side. Further, this paper uses a
traditional hysteresis controller for generation of switching signals
for the Voltage Source Converter (VSC). Moreover, switching of DSTATCOM
between Current Controlled Mode(CCM) and Voltage Controlled Mode(VCM) is
carried out so that only single DSTATCOM serves the problem for current
and voltage related Power Quality problems. Simulations are carried out
in MATLAB/Simulink environment to validate the proposed scheme and
results indicate that the unity power factor is achieved during CCM mode
and voltages in all the three phases at PCC are maintained at 1 p.u.
during VCM
mode.