1. SSLB Running in Pump mode Transmission Loss optimisation
Present Operations
400KV SSLM Nunna Feeders Kept out
Two out of Five 400KV Circuits Between Gajuwaka / Kalpaka and Nunna Kept out
SSLB Running in Pump mode During Night off Peak Hours
Power to SSLM fed through Gajuwaka-Vijayawada-Khamam-Mamidapalli-SSLM or
Kalpaka-Khamam-Mamidapalli-SSLM
Presently step up of 100 MW at only at Vemagiri.
Power taking Circuitous route Increased loss
Unable to close 400KV SSLM Nunna Feeders Due to high Voltage at Nunna.

2. SSLB Running in Pump mode Transmission Loss optimisation
Loss optimisation Proposal
Action to be taken
Close one of 400KV SSLM-Nunna one circuit
Open one of 400KV SSLM-Mamidapalli circuit
Loss reduction 10MW
Problems in closing one of 400KV SSLM-Nunna one circuit
High Voltage at Nunna
Reluctance for charging from SSLM
Proposal for controlling Voltage at Nunna
Open One of400KV Kalpaka-Vemagiri-Vijayawada
Open one of 400KV Gajuwaka –Nunna feeder
Open other 400KV Kalpaka-Vemagiri-Vijayawada when injection at Vemagiri is less
(Opening of Kalpaka-Vemagiri-Vijayawada has more Sensitivity for voltage at Nunna about 6-8KV)

3. PIC 3.2

4. Closing 220KV Sulurpet Gumudupondi
Present Position
400/220KV ICT at Nellore commisioned
220 KV Nellore – Sulurpet feeder LILO at 400KV Nellore Station
220 KV Nellore – Renugunta feeder LILO at 400KV Nellore Station Yet to be compleeted
Flow through 400/220KV ICT at Nellore is about 100MW
Problem faced
Sulurpet Radial Insufficient anchoring at 400KV Nellore
High voltage and large variations
Low voltage at Sulurpet
Advantage of closing 220KV Sulurpet Gumudupondi
Quick study indicate
Voltage at Sulurpet increase by around 7to 8KV
Short circuit level will increase at Sulurpet increase due to proximity with Generating stations of TN
Stability of the grid increase