The Kerala power system consists of 13 hydel stations, 11 small hydel stations, 2 captive power plants, 2 thermal stations, 3 IPPs, and 1 wind mill. The grid is connected to the Southern Region Transmission system through two 400kV double circuit lines at Madakkathara and Trivandrum. There are 5 major inter-state transmission lines. The major substations include one 400 KV sub-station, and fourteen 220 KV substations and four 220kV substations under construction. The main grid comprises of the 220 KV system.
The net energy requirement for the year 2006-07 is estimated to be 14,687mu. Out of this about 7,457mu is expected from hydel sources, 7804 from central generating stations, and from the remaining sources. The present peak load demand is about 2700MW and is expected to increase up to 2,800 MW during April/May. The hydel potential is about 6130MU if the inflow is normal. We have a storage capacity of 4083MU.
LOAD DISPATCH CENTRE
The grid is managed by the State Load Dispatch Station situated at Kalamassery. There are 3 Sub Load Dispatch Centres – at Thiruvananthapuram, Kalamassery and Kannur (Kanhirode).The load Dispatch activities are carried out with the aid of state of art technology computerized Supervisory Control and Data Acquisition System (SCADA). Real-time data from 30 Remote Terminal Units including generating stations and major sub-stations are acquired at the Load Dispatch Station. One more RTU is being installed. The data acquisition is through the communication network installed and maintained by the Board comprising of MW link from Thiruvananthapuram to Kalamassery and FO link from Kalamassery to Kannur.Data from remote stations are collected through Power Line Carrier Communication Network (PLCC) to the nearest nodal station in the broadband network. The state LD Station is connected to the Regional Load Dispatch Centre, Bangalore through FO link for real time data transfer. The real time generation details of all central sector stations are made available through the SRLDC.
The state load dispatch centre schedulesgeneration from various generating stations, central sector stations and IPPs depending on the load condition and the real time frequency. Transaction of unscheduled energy from the pool when the frequency profile is favourable is coordinated by the SLDC effectively. The load Dispatch Centre also monitors the transmission system and issues sanction for shutdowns. Water availability, inflow, consumption, demand etc. are daily collected and monitored in the Load Dispatch Station.
The Load Dispatch activities are co-ordinated bythe Chief Engineer, System Operation, Kalamassery. The major activities undertaken by this wing are
1.
Daily scheduling of
Generation
2. Short term and long term planning of generation schedule
3. Preparation of Load Generation Balance Reports on short term and long term basis
4. Verification of energy drawals from various central generating stations and Regional Energy Accounts
5. Verification of energy availed on unscheduled basis from the central grid depending on the frequency.
6. Certification of energy generated from all internal generating stations and the energy received on the grid.
7. Maintenance scheduling of generating units and transmission lines.
8. Economic load dispatching
9. Grid discipline
10. Load forecasting and demand estimation
11. System security and islanding facility
12. Black start preparedness
13. Event analysis and preventive measures
14. Coordination with neighbor Grids
15. Public relation and consumer interaction.
16. Certification of availability of generating stations, and transmission system.
17. Maintenance of the communication network, communication equipments and SCADA system
18. Protection coordination, commissioning and
troubleshooting of protection schemes at all substations and generating
stations.
19. Performance monitoring of major grid elements like power
transformers, instrument transformers, generators, capacitor banks, etc.
20. Undertakes testing and commissioning of protection
schemes of major EHT consumers on a payment basis.
The Load Dispatch Station activities are technically supported by by the communication wing and protection wing under the control of three Dy. Chief Engineers stationed at Thiruvananthapuram, Kalamassery and Kannur.
The communication wing is responsible for the upkeep of all communication networks, the SCADA system and the associated software for Energy Management
The Protection Wing, more popularly known the Relay Wing, is responsible for ensuring selectivity and sensitivity to fault clearance in the grid to achieve stability of the power system.
The LD Activities are controlled by the Dy.Chief Engineer, Grid, stationed at Kalamassery. The LD activities aim at the optimum usage of hydel reserves, unscheduled energy and follow the principles of merit order dispatch to minimize the operating cost of the grid.
Plans for future
The Load dispatch activities have to take care of the additions and modifications to the grid. The data from the major substations and generating stations added to the grid have to be acquired and processed. This is accomplished under the plan scheme “Modernisation of LD”.
The communication network at present comprises predominantly of PLCC. As the requirement of data increases, more stations are to be hooked on to the wideband network. This requires installation of new wideband links. The PLCC network has to be expanded and reconfigured with the modifications / additions made in the grid. Such works are attended by the communication wing under this office and is accomplished under the plan scheme “Modernisation of Communication”
For ensuring the security and reliability of the grid, the protection scheme of all grid elements is to maintained and upgraded so as to suit the grid requirements. Replacement of faulty, unserviceable and obsolete protection scheme is being processed. The work is accomplished under the plan scheme “Modernisation of Relays”
