Morgan

Following its final investigation into the July 15 islandwide blackout, the Office of Utilities Regulation (OUR) yesterday issued five recommendations the Jamaica Public Service Company Ltd. (JPS) should follow in order to prevent the recurrence of such an event.

J. Paul Morgan, director general of the OUR, outlined the recommendations to journalists at the OUR's New Kingston office.

Among the recommendations was that the JPS must revisit its protective relay co-ordination scheme to ensure its adequacy and that the company reinforces a 138 kilovolt grid between the south and north coast.

It was also recommended that:

JPS should review the dynamic stability of the generating system under normal operating conditions and probable contingency scenarios.

Ensure that back up systems for communication are placed where currently there is none.

All JPS generation stations, Independent Power Producers (IPPs) and JPS systems control centres must be time synchronised as a matter of urgency.

The island was plunged into darkness on July 15 after lightning struck a steel tower at the Duncans/Bogue transmission link. Failure of the protective relays at the substation to respond to damage led to the collapse of the system.

No backup

Additionally backup relay systems at the adjacent Bellevue and Kendal substations did not operate as expected.

"The non-operation of the relays at Duncans was due to the fact that the voltage supply to the relay circuits, provided by batteries was not operable," Mr. Morgan told journalists yesterday.

He noted that JPS systems controllers were not aware of the situation as the voltage supply to the relay circuits remote alarm system, was not in place.

"The system subsequently became unstable because the critical clearing time for system stability was exceeded (.5 seconds) due to non-clearance of the fault," the OUR head said. "Remote backup systems did not operate, possibly due to relay coordination problems or early dissipation of the fault."