One-day workshop on Transfer
capabilities studies (TTC/ATC) by
NRLDC
Case study for Punjab and Delhi
14.03.2022
Methodology to assess TTC/ATC
• Generation of a control area kept
fixed and demand increases up to the
limit where the congestion in
network/Constraint observed.
• For a certain Demand, Import
capability is assessed for different
generation scenario.
Detailed Procedure for relieving congestion in real time
operation under Regulation 4 (2) of the Central Electricity
Regulatory Commission (Measures to relieve congestion in real
time operation) Regulations, 2009 3.10.2 states that while
assessing TTC limits there should not be violation of
transmission element loading limit in n-1 contingency case.
Change in
Demand
Change in
generation
Punjab TTC/ATC
Punjab TTC/ATC
Generation Considered
State own generation = 6100MW (excluding Intrastate Solar Gen)
N-1 Non-Compliance
ICTs at Nakodar and Rajpura, With high generation at Rajpura TPS (>1300MW), the
loading of 400kV Rajpura TPS-Rajpura D/C is observed to be N-1 non-compliant
TTC/ATC of Punjab for
Solar and Non-Solar
hours
(*TTC/ATC has been assessed
considering frequent outages of
TSPL units for different cases)
Punjab Demand, Import and N-1 Non-Compliance of ICTs
N-1 Loading limit: 710MW
Punjab ATC: 7100MW
N-1 Loading limit: 1110MW
N-1 Loading limit: 460MW
N-1 Loading limit: 1220MW
Delhi TTC/ATC
Delhi Power transmission Network
Transmission Network
Transmissi
on line
400kV
220kV
Intra
OH
UG
state
(CKMs) (CKMs)
(nos)
10
246
3
108 ~1108 ~174
108 nos of line
10 nos of line
Nodes
400/220kV
220/132or 66
kV
Transformatio
Nos n capacity
(MVA)
7
11040
49
~11590
New 400kv S/s
Delhi TTC/ATC
Generation Considered
State own generation = 600MW
N-1 Non-Compliance
N-1 non-compliance issue at 400/220kV Bamnauli and Mundka ICTs. After
commissioning of 400kV Dwarka(PG) S/s N-1 issue at Bamnoli got relived however
Mundka would still be N-1 non-compliant with 2*315MVA ICTs.
TTC/ATC of Delhi
TTC= 6800 MW
ATC= 6500 MW (Considering RM as 300 MW)
400/220kV, 1500
MVA, Dwarka-I GIS
commissioned on
Feb’22 (LILO of One
Ckt of Bamnauli Jhattikara at 400kV
Dwarka (PG) S/s.
 After commissioning of S/s and 400/220kV, 500MVA ICT-1,2&3, loading on Bamnoli
ICTs reduced significantly.
 220kV Dwarka-Papankalan-1 ckt-1&2 is newly commissioned line and significant load
of Papankalan-1 is being fed by Dawarka S/s through this D/C line, earlier it was fed
by Bamnoli.
 220kV Narain400kV Dwarka a-Papankalan-3 ckt-1&2 LILOed at 220kV Dawarka.
 Relief on Mundka ICTs is only around 50MW, loading is still closed to N-1 loading
limit, Hence shift of 400/220kV, 315MVA ICT-1 from Bamnoli to Mundka was
recommended.
Delhi Demand, Import and N-1 Non-Compliance of ICTs
Delhi ATC: 6500MW
3
N-1 Loading limit: 1150MW
N-1 Loading limit: 650MW
Monitoring of Import, ATC violation of each states along with critical ICTs loading and ICTs N-1
Non-Compliance in a Single SCADA display at NRLDC
Thank You