In the process of charging electric vehicle

the charging facilities(CF)should be able to reliably respond to the protection of battery management system(BMS)when the power battery and BMS are abnormal. This paper analyzes the protection demands of BMS

and defines the response rate of CF to the protection demand of BMS. By referring to the existing standards and engineering practice

the indicator system of response rate is developed

which covers the evaluation indicators of power battery failure and BMS failure. The weights of indicators are calculated by the analytic hierarchy process(AHP)method. Finally

with the assessment of the response rates of two CFs

the weak link of charging system is found according to the indicators of single response rate and comprehensive response rate

while measures to improve the response rate are proposed. The result shows that the response rate is able to quantify the response ability of CF to BMS protection demand.