Parallel Operation of Capacitor-less D-STATCOM to Allow More Penetration of Photovoltaic Systems in Distribution Network

The rapid proliferation of distributed photovoltaic (PV) systems in the distribution network causes many challenges to utilities including changing in voltage profile and exacerbate the harmonic power issues. In this context, this paper proposes the use of parallel D-STATCOM devices dispersed within the distribution network to provide support that enables more penetration of solar PV systems to the distribution network. With a form-factor similar to a standard pad-mounted transformer, the D-STATCOM provides reactive power to control voltage profile, and harmonics compensation to minimize the distortion in upstream voltages and currents. Modified synchronous reference frame method is used to generate the reference currents of the D-STATCOM unit with finite control set model predictive control (FCS-MPC) used to control a matrix converter. This arrangement makes it possible to use inductive energy storage rather than electrolytic capacitors, which have been proven to be amongst the most failure-prone components in a power electronic circuit. Simulation results using MATLB/Simulink are presented to validate the effectiveness of the technology.