Abstract:An analysis is made of the design of lightning current energy coordination relevant to Surge Protective Devices (SPDs). The coordination between singlelevel SPD and protected device is studied, and the formulas for computing the maximum oscillation protection distance and maximum coupling distance are used to determine the successfulness of the coordination. The coordination between multilevel SPDs is also studied, putting the emphasis on the coordination of twolevel SPDs (switch type and voltagelimited type). The differential equation of transient voltage drop is adopted, and the size of the decoupler is determined by means of different lightningcurrent wave forms. The feasible procedure of lightning current energy coordination design for SPDs is proposed.