Control and implementation of multifunctional microgrid with seamless synchronization capability

A microgrid with a solar photovoltaic (SPV) array, wind generator, battery energy storage (BES), and a bidirectional DC–DC converter with seamless transition capability from on-grid mode (OGM) to off-grid mode (FGM) and grid reconnected mode is presented. This microgrid, based on renewable sources, increases the authenticity and sustainability of the supply and has the ability to feed the load in OGM and FGM as well as during mode shifting. The undetermined disturbances and unpredictability of the microgrid in OGM are managed by a sixth-order complex filter (6thOCF)-based control. With this control, the load current quadrature fundamental component (LCFC-Q) is obtained without a DC offset even during voltage imbalances. This control provides effective mitigation of harmonics and monitors the flow of active power, which improves the grid current quality. The control approach based on a resonant plus proportional resonant (R+PR) controller along with the harmonics compensation ability is used to control the microgrid in FGM. A dual 6thOCF (D6thOCF) is cascaded in series with the phase-locked loop for effortless synchronization of the grid. This enhances the system performance without affecting the stability. The microgrid performance is validated through simulated and experimental results under dynamic and steady-state conditions.