The accumulation and dissipation of space charge in insulation layer caused by cable aging has great influence on insulation property. Consequently
two retired and a spare 110 kV XLPE cables were chosen and the space charge distribution of different layers was measured by pulsed electro-acoustic(PEA). Meantime
the relationship between space charge characteristics and the cable aging was analyzed preliminarily. The results show that the accumulation of positive charge and heterocharge(except the positive charge) in different locations increases due to cable aging; for the diversity of unit volume mean density is tiny
the status of cable aging is difficult to be estimated; at the beginning of charge dissipation phase
the unit charge density risen by the charge detrapping and the diversity of initial value of different layer is quite different; then the charge releasing rate decreases gradually with time so that it will be suitable for assessment of the trap energy level change of cable insulation. In conclusion
the change of unit charge density and diversity of trap energy level will be better for the assessment of the cable aging state.