Adaptive Grid-Supportive Control for Solar-Power Integrated Electric-Vehicle Fast Charging Station

Abstract

Though the Medium-voltage (MV) grid-connected solid-state-transformer ( SST ) based plug-in electric-vehicle fast-charging station (PEV-FCS) solutions provide a reduction in grid side current-stress, integration of solar-power in such SST -based PEV-FCS (which can potentially reduce grid side current-stress further) and its implementation with grid-compliant control is not explored in literature. In this paper, an adaptive automatic generation control supportive maximum power point tracking (AGCS-MPPT) technique for solar-power integration is proposed and experimentally validated for a bidirectional SST -based PEV-FCS while following the EN 50530 standard's testing sequence. Respective European and Californian MPPT efficiencies ( ξEuro , ξCEC ) of 99.50%, 99.55% and 99.49%, 99.55% are observed for solar-power integration through AGCS-MPPT technique during G2V and V2G functional modes of the PEV-FCS, which are better compared to those of state-of-the-art technique (SoAT) and improved perturb and observe (P&O) MPPT algorithms. Unlike the SoAT and P&O, the AGCS-MPPT algorithm assists the PEV-FCS in adhering to the utility grid's power ramp-rate constraint while integrating intermittent solar-power, both during ξEuro -test and ξCEC -test sequences. The AGCS-MPPT also displays excellent MPPT efficiency ( ∼ 99.2%) and solar-power integration performance during the dynamic-test sequence as per EN 50530 standard. Grid side current's THD < 2.2% and near unity power-factor (UPF) at grid side are observed during the experimentation of PEV-FCS under various solar-power penetrations.