Abstract: This paper proposes a new energy function with additional ratio coefficient of kinetic and potential energy for the transient stability analysis of grid-following converters under large disturbances,which improves the inherent conservatism of the traditional energy function. First,the form of the energy function is calculated based on the undetermined gradient method;second,with the positive definiteness of the energy function as a constraint,the range of additional coefficient is preliminarily determined;furthermore,the dissipation of the energy function is determined based on gradients and differential equations,further narrowing the range;thirdly,the stability domain of the energy function is analyzed and compared,and suggestions are proposed for improving conservatism. Finally,the conclusions obtained are applied to the electromagnetic transient simulation model of grid-connected converters,and the effectiveness is verified.