MSTOGI-FLL-ROGI Based Frequency Adaptive Control for a Single Stage SPVA-BES-BDC-DG Set Connected Standalone Microgrid for Remote Areas

The operation of a standalone microgrid (MG) is severely affected by the presence of local nonlinear loads at the point of interconnection (PIC), which tend to degrade the power quality of the MG. Moreover, in MGs connected with diesel generator (DG) sets, the frequency varies with loads, which leads to poor power quality due to erroneous estimation of the fundamental components. To solve these problems, this paper presents a mixed second and third order generalized integrator with a frequency locked loop (MSTOGI-FLL) prefilter cascaded with a reduced order generalized integrator (ROGI) filter-based control for a solar photovoltaic array (SPVA), a battery energy storage (BES), and a synchronous reluctance diesel generator set (SynRDG) based standalone microgrid. The control improves the operation of the MG by providing enhanced harmonic attenuation and DC offset rejection from the DG currents and PIC voltages during distorted or single-phase load conditions without degrading the dynamic performance of the filter. The control makes the filter adaptive to the DG set frequency, which enhances the filter performance. A power management scheme (PMS) is presented to utilize the SPVA-BES combination and it minimizes the DG set operation. The presented control is compared with other GI-based controls in terms of dynamic performance, frequency tracking, and filtering capability. The MG performance is analyzed under several dynamic conditions using simulation and hardware results.