Error analysis of insulation resistance detection method in battery energy storage system
Insulation resistance detection is crucial for the safe operation of battery energy storage systems. This study addresses the significant and random measurement errors associated with the commonly used balanced-unbalanced bridge method. By establishing a computer simulation model of this method, the research investigates the error-influencing factors in insulation resistance detection. The analysis quantitatively examines the impact of these errors, focusing on voltage measurement error bias and accuracy. To address the engineering challenge of a limited and imprecise measurement range due to reduced positive bus insulation, an improved balanced-unbalanced bridge method is proposed. This improvement includes a theoretical foundation and a detailed methodology for selecting bridge resistance. Furthermore, the study tackles the issue of diminished measurement accuracy and insulation monitoring dead zones when both positive and negative insulations are compromised. A variable resistance switch bridge method, derived from the three-dimensional surface analysis of the simulation model, is suggested to enhance detection accuracy under such conditions. Field tests conducted at an engineering site confirm the validity of the error analysis and the appropriateness of the parameter selection. The findings offer valuable insights and a theoretical framework for designing and selecting parameters for the insulation monitoring function in battery management systems.
battery energy storage systeminsulation detectioncomputer simulationerror analysis
万方数据
维普
