One problem, one method, one result.

Situation

Potential transformers and ring main units on a 33 kV network were failing repeatedly. Replacement had not stopped recurrence, which meant the cause lay in the system rather than in the individual units.

SLPL was engaged through the project consultancy to establish why.

What we did

Performed a 33 kV system study and RCA covering fault levels, switching transients, earthing, PT loading and ferroresonance risk. Reviewed protection settings, disturbance records and failure patterns to identify the common system-level cause.

Result

Root cause was identified as transient overvoltage/ferroresonance conditions affecting the PT–RMU combination. Recommended revised PT protection, damping/earthing measures and switching/protection coordination, eliminating the recurring failure mechanism.

Situation

The substation forms part of the transmission build-out for the largest renewable energy park in India. At 765 kV, gas insulated switchgear leaves no margin for a test regime that is anything less than complete.

SLPL was appointed for testing and commissioning of the GIS.

What we did

Executed comprehensive testing and commissioning of 4 GIS bays, covering primary equipment, protection, control, interlocking, and associated systems. 7 engineers were deployed for coordinated field testing, verification, and commissioning.

Result

All 4 GIS bays were successfully tested and commissioned with zero schedule variance, supporting timely energisation and project execution.

Situation

A 220 kV pooling substation evacuating 300 MW of solar generation. Every hour the substation is unavailable is generation that cannot reach the grid, so availability is the metric the contract turns on.

SLPL took over operation and maintenance of the station.

What we did

Managed end-to-end O&M of the 220 kV, 300 MW solar pooling substation, with preventive maintenance, condition monitoring, fault diagnostics, breakdown response, and 24×7 operational support.

Result

Maintained 99.9% availability while attending 13 breakdown events, with rapid fault isolation and restoration to minimise generation losses.