Final Client

Scope of Supply

The supply includes the provision of protection coordination study for the extension of Matambo Substation, in Tete, Mozambique.

System Description

The following protection system was considered:

    • Transformer (220/66/33kV) protection:
      • 2 x transformer low impedance differential protection (87), overload protection (49) and residual over current (51N)
      • 3 x high impedance differential (87H) for restricted earth fault protection
      • Primary overcurrent protection (50/51)
      • Secondary overcurrent protection (50/51)
      • Breaker failure protection (50BF)
    • 220 kV busbar protection
      • 3 x (one per phase) low impedance protection for busbar protection (87B)
    • 66 kV outgoing feeder
      • Line distance protection (21)
      • Earth directional overcurrent (67N)
      • Autoreclosure (79)
      • Breaker failure protection (50BF)
      • Voltage check and syncrocheck (25)
    • 33 kV bays
      • Overcurrent protection (50/51)
      • Breaker failure protection (50BF)
    • 33 kV and 66 kV Busbar
      • High impedance differential protection (87H) for busbar
    • Auxiliary transformer 33/0,4 kV
      • Overcurrent protection (50/51)


Description of Activity

ENGIPROT work team was responsible for study the substation equipment for proper protection and selectivity coordination, including the existing bays.

Customer Benefits

The settings protections definition allows to safety operate the substation and the network.