Establishing an accurate white box electromagnetic transient simulation model for static var generators (SVGs) is a prerequisite for analyzing the voltage stability characteristics of the power grid. However, existing models often use generic control structures and parameters because of confidentiality issues of the SVG controller, resulting in significant discrepancies between transient output characteristics and actual performance. To solve these issues, this paper proposes an electromagnetic transient model identification method based on the fault ride-through (FRT) evolution characteristics of the SVG manufacturer packaged black box model. First, this paper analyzes topological characteristics of the manufacturer’s black box model, and clarifies its FRT evolution characteristics through multi-condition FRT response testing. Then, by analyzing the impacts and pathways of transient switching processes of different control parts of the SVG, a controller structure identification method based on the evolution form of the FRT response is proposed. By analyzing the influencing mechanism of different SVG control parameters on FRT response characteristics by stages, a step-by-step identification method for controller parameters based on FRT response amplitude is proposed, forming a white box electromagnetic transient model identification method system for the SVG. Finally, a comparison is made between the established white box simulation models of different models and the corresponding manufacturer’s black box models in terms of FRT response characteristics. This finds that the error is much smaller than the allowable error of the current standard, proving the effectiveness and universality of the proposed method.