Advanced control scheme and dynamic phasor modelling of grid‐tied droop‐controlled inverters

This paper develops an advanced scheme, modelling, and analysis of power flow control intended for grid-connected droop-controlled VSIs within a single-phase microgrid (MG). The proposed scheme includes calculation method based on enhanced second-order generalized integrator frequency-locked loop (ESOGI-FLL). Contrary to the existing methods that use low-pass filter (LPF) with low cutoff frequency reject grid voltage distortion achieve average power, which may result in reducing speed, involved ESOGI-FLL can offer fast transient response benefits from high filtering capability sub- low-order harmonics. In addition, provides total rejection DC offset, is another issue adversely affect accuracy traditional methods. Thus, this proposal contribute improving speed computation make immune disturbance, thereby enhancing performance control. On other hand, dynamic phasor modelling approach adopted considering dynamics ESOGI-based calculation, instead LPF transfer function used describe related works. small-signal model VSI line impedance R/X ratio as well describing are derived. Using these models, closed-loop grid-interactive inverter including controller obtained. system stability assessed, helps determine properly controller's gains. A simulation study carried out MATLAB/Simulink™ PSIM's processor (PIL) platforms assess effectiveness approach. results confirm regulate real reactive powers good performances when subject several working conditions.