| Popis: |
With the ever-increasing complexity of disturbed Power Systems, the method of protection using electromagnetic relays may not be adequate to afford appropriate discrimination especially when the fault current flows in parallel paths. Because the electromagnetic relay has slow response time, and the fact that it is a mechanical device and has moving parts, over a period of time, these moving parts will wear out and the relay will fail. To overcome these drawbacks, a more reliable means of system protection was carried out using solid-state contactless devices. A modular technique using five blocks made up of power supply unit, current sensor unit, voltage sensor unit, switching unit and output unit were used in the study design. A 66 kV power network was used to test the reliability of the protection designed circuit. Result shows enhanced system security. |
