One of the most important way to achieve net zero is utilization of renewable energy and most renewables are integrated into the grid via power electronic converters. However, the converters generally lack rotational inertia, which reduces the inertia of the power system and deteriorates the system stability. To address this problem, this paper investigates the grid form control (GFM) of grid-connected inverters. By exploring the virtual impedance of inverters with virtual synchronous generator control and optimizing the virtual inertia and damping coefficient, an enhanced grid forming control strategy is proposed to improve the power grid support capability of converters for renewable energy integration, leading to improved stability of power system and better fault current controllability during symmetrical AC faults. Finally, the influence of voltage-current loop on the performance of GFM converter is analyzed, and the effectiveness of the proposed control strategy is further verified.