The invention discloses a control strategy for pre-charging and electrifying a
power battery. The control strategy comprises the following steps: calculating a
capacitance * resistance limit range value and a sampling precision limit range value; collecting a plurality of groups of pre-charging proportions Kn, and calculating the sampling precision xK in combination with the sampling frequency; judging xK, and if xK is out of tolerance, recording a sampling precision out-of-tolerance fault; calculating an actual
capacitance * resistance value RC; judging the RC, and if the RC is out of tolerance, recording
capacitance or resistance out-of-tolerance faults; calculating a pre-charging proportion Kx with xK, and taking the pre-charging proportion Kx as a judgment basis for successful pre-charging; whether the pre-charging proportion collected within the allowable time tA reaches Kx or not is judged, and if the pre-charging proportion does not reach Kx, the actual pre-charging time tR and the allowable time tA are calculated; if tR is less than or equal to tA, reporting a pre-charging
timeout fault and other reasons; if tR is greater than tA, reporting a pre-charging
timeout fault, and recording the fault; and disconnecting the main negative (positive)
relay. When the
relay is pulled in after pre-charging is completed, large
impact is avoided, the service life of the
relay is prolonged, meanwhile, faults can be recorded, and positioning and overhauling are convenient.