This chapter presents the analysis of grid-forming inverter connected to a utility grid. Two types of controllers namely droop and virtual synchronous generator (VSG) are used to control the frequency and voltage of the grid-forming inverter. For increasing the transmission capacity and to improve the system stability, a series compensated line is taken in which the series compensation level (SCL) is changed making the grid stiff or weak, but by increasing SCL beyond a limit can make the grid unstable and can bring more oscillations. The performance analysis of system is analyzed for both the controllers by taking different parameters of droop and VSG, as well as for different grid strength by changing the values of SCL. The performance is studied by analyzing oscillations in the frequency of the inverter.