Featuring soft ionic lattices of PbI6 octahedral frameworks, halide perovskites confront multiplicate force-driven structural collapse (e.g., humidity, heat and illumination) initially on the surface and finally in the bulk, and...

This study proposes a unified voltage regulation and maximum power point tracking (MPPT) method for photovoltaic (PV) sources in islanded direct current (DC) microgrids based on modified model predictive control (MPC). The method enables the PV sources to track the maximum power and serve as voltage sources for DC-bus voltage regulation when their available power is sufficient. Based on the proposed modified predictive model, the desired duty cycles can be calculated and directly applied to the PV sources in a constant switching frequency without a modulator. Real-time laboratory tests show that the PV sources can support the DC-bus voltage without energy storage (ES) and can proportionally share the load. Moreover, power oscillations and voltage ripples of the modified MPC get greatly attenuated compared with the traditional MPC under the same sampling frequency.

Accumulated halide defects on the buried interfaces of halide perovskite layers have exacerbated undesirable nonradiative recombination in the n–i–p perovskite photovoltaics, but are challenging to be passivated—the commonly used passivation molecules at buried interfaces of perovskite layers would be inevitably eroded in the solution processes of perovskite deposition. Regarding the solvent incompatibility, herein, the ZnO–EA/SnO2–Cl electron transfer layers (ETLs) terminated with functional sites (i.e., ethanolamine (EA) ligands on ZnO and Cl− ions on SnO2) to spontaneously heal the buried interfaces of perovskite layers are customized. The specialties of ZnO–EA/SnO2–Cl for defect passivation are revealed: 1) formation of ZnO–EA–Pb2+ coherent interlayers at the EA‐terminated ZnO‐perovskite interfaces effectively offsets the I vacancy defects of perovskites; and 2) spontaneous halide exchange between Cl−‐terminated SnO2 and unstable I−‐terminated perovskites enables the formation of FA2Sn(ICl)6‐like coherent interlayers. Thus, the customized termination of ETLs’ surface reduces the halide‐defect‐triggered nonradiative recombination at the buried surfaces of perovskite, enabling the fabricated n–i–p planar modules (6 × 6 cm2) with power conversion efficiencies approaching 18% and elevated stability. These findings provide desirable guidelines for interfacial carrier transport between perovskites and ETLs.

High integration of PV diminishes system inertia, which jeopardizes the system frequency stability. Adjusting PVs’ output according to demand is an active power control method requiring no energy storage devices, which realizes grid frequency support by a certain reserved power of PV. To equally reserve power between different PVs without communication, this paper combines the operation characteristics of the PV module on the right side of the maximum power point and proposes the characteristic of power reserve and adaptive power reserve-frequency supporting control. Furthermore, irradiance and temperature sensors, cumbersome mathematical computation, and accurate measurement of PV module parameters can be eliminated. Finally, simulations are provided to validate the effectiveness of the proposed control strategy.