Presentation on theme: "Transmission Distribution Interface bottlenecks and strategies for improved grid Stability By Engr. A.S.A Bada CEO (TCN)"— Presentation transcript:
Transmission Distribution Interface bottlenecks and strategies for improved grid Stability By Engr. A.S.A Bada CEO (TCN)
GRID INTERFACE BOTTLENECKS Major Causes include : Radial state of network Spatial network coverage Transformer Capacity Constraints Line Capacity Constraints Switchgear Conditions Grid indiscipline Distribution network Conditions Frequent trippings/Persistent faults
STATE OF NETWORK Radial State of network – Steps Taken: NIPP presently constructing the closing of the loop to Jos with a DC 330KV line Spatial Network Coverage – Steps Taken: 26No. Lines and Substation projects awarded in 2010 and 18No. Lines and Substation projects to be awarded before the end of this year (4 New substations to be constructed in the North Eastern part and 5 New Substations in the NW )
ON-GOING CAPACITY STRENGTHENING PROJECTS Ctd TCN expects delivery of Power Transformers from 1 st quarter of 2012 – 4No. 300MVA 330/132KV Transformers – 5No. 150MVA 330/132KV Transformers – 10No. 100MVA 132/33KV Transformers – 10No. 60MVA 132/33KV Transformers
LINE CAPACITY CONSTRAINTS Steps Taken: Gombe – Yola 330kV line has been energized 2 nd Benin – Ajaokuta 330kV line has finally been rehabilitated 3 rd Benin –Onitsha DC 330kV line to be commissioned soon Re-conductoring of weak and old lines (e.g Aba – Itu, Itu – Calabar, Afam – PH, Delta – Effurun, Ota - Papalanto) with higher thermal capacity conductors are in various stages.
OUTCOME OF STRATEGY MEETINGS #Drop down Sub. By WBankSource Line 1330/132KV Substation at Ogijo (Ikorodu) Egbin – IkejaWest 330KV Line 2330/132KV Substation at EpeOmotosho – Aja Line 3330/132KV Substation at New Kano Kaduna – Kano 330KV line 4132/33KV Substation at Choba - PH Omoku – PH Mains Line 5132/33KV Substation at Awkunanu - Enugu New Haven – Orji Line 6132/33KV Substation at KaltugoGombe – Yola Line
URGENT CONCERNS Too frequent 33KV trippings Inadequate notification of expansion projects
33KV TRIPPINGS FOR NOV. WK 1 # DISTRIBUTION ZONES TOTAL NUMBER OF TRIPPINGS TOTAL ENERGY Undelivered (MWH) 1 ABUJA1261, BENIN1254, EKO554, ENUGU20815, IBADAN191 4, IKEJA433, JOS711, KADUNA KANO PH1214, YOLA
MITIGATION STRATIGIES FROM DISCOs Submission of accurate data on customer population and installed capacity (MVA) De-loading of 33KV Feeders through network expansion Explore use of lattice towers for long 33KV Lines Due to inadequate generation power should be given to some feeders then transferred to the others over time RATHER THAN pro-lateral sharing of power on all the feeders at the same time
MITIGATION STRATIGIES FROM DISCOs Adherence to operational instructions Gradual phase out of wooden cross arms with fibre Movement of load on designated under frequency relays should henceforth stop Disciplinary actions should be meted out on erring staffs
MITIGATION STRATIGIES FROM DISCOs Supervising operators should henceforth be alive to their responsibilities Issuance of a circular from their respective CEOs demanding strict adherence to operational instructions
Further Key Transmission Grid Challenges Due to urbanization and environmental issues, it is becoming increasing difficult to acquire Right- Of-Way for new lines Increased power demand due to growth in industries and population Vandalization of transmission lines Adverse Weather Conditions Poor power quality Transmission grid upgrades cannot keep pace with power demand
STRATEGIES - Work is on-going on grid expansion. - Significant Investment is being made to effectively double existing capacity through the NIPP intervention -Line trace issues (mitigation against frequent line trips) have been taken more seriously with focus on contracting companies with requisite tools to work on difficult terrains -Frequency stability has been largely achieved with some units in Delta, Kainji and Egbin providing frequency support in form of reserve margins -Deployment of FACTS facility at strategic node of the network (e.g Kano, Gombe) -Work has commenced in deploying the Supergrid network
330KV GRID STRUCTURE AFTER COMPLETION OF ALL ON-GOING PROJECTS SAPELE P/ST. Okitipupa Geregu 2015 : 2 nd Circuit Agip Zaria 2015 : new Mambila Hydro Some 330kV lines especially in Lagos and Delta areas could not be indicated on this geographical Map. See attached single diagram for Details.
TRANSMISSION GRID STRUCTURE WITH THE SUPER GRID IN PLACE SAPELE P/ST. Okitipupa Geregu 2015 : 2 nd Circuit Agip Zaria 2015 : new 700KV LINES – SUPER GRID 700 / 330KV SUBSTATION Mambila Hydro Some 330kV lines especially in Lagos and Delta areas could not be indicated on this geographical Map. See attached single diagram for Details. NOTE: TCN NETWORK WITH SUPERGRID