This paper analyses the reasons for the failure of five consecutive single-train fast starting of emergency diesel generators in nuclear power plants. Based on the starting dynamics of diesel generators and governor control principles, and considering the starting characteristics of the respective units, the study identifies the root causes and key reasons affecting single-train fast starting among various contributing factors. The study extracted a set of methods for handing emergency diesel engine set faults. Employing a comparative analysis of test results and diagrams, the paper proposes solutions to ensuring the success of five consecutive single-train fast starting of emergency diesel generators for the first time in the world.