Substation Control and Automation (SCADA)

SCADA System :
RTU (Remote Terminal Unit) installed in distribution & transmission substations and SCADA system can make substations unmanned and remote monitoring and controlling substations possible. In Power Systems SCADA has widespread application in generation, transmission, distribution and substation automation.

SCADA Technology
1. High ReliabilitySCADA system design can realize high reliability & availability.
2. Monitoring SubstationsAutomatic monitoring and displaying of substation condition can be conducted based on the information from RTUs.
3. Operation of Substation equipmentManual operation by operators and automatic operation by SCADA system are possible.
4. Automatic MessageSCADA system can edit messages about fault information, etc. and messages are reported to related offices automatically.
5. Substation Operation Supporting FunctionVarious information needed for substation operation (operation record, load status record, etc.) can be generated automatically.

ADVANTAGES:
1. Eliminates operators working on shifts in substations. Assuming 8 operators in 132 KV substations. The annual expenditure per operator is about Rs. 2 lakh.
2. Eliminates manual error in meter reading and calculations.
3. Eliminates data transmission by post or fax.
4. Automation, state of art technology and reliability
5. remote operation on circuit breakers and line isolators.On line real time monitoring of substation at HQ.

The Hardware
The substation control system, being responsive to a plurality of status input signals from various power system assemblies includes a plurality of input/output modules, each having a fiber-optic transceiver capability, wherein wire connections are used to communicate the status signals from the power system assemblies to input contacts of the respective I/O modules. The output signals from the I/O module are applied to a fiber-optic line. The system also includes a plurality of logic processors, each responsive to the signals on a fiber-optic line from a plurality of input-output modules for application to a plurality of protective relay devices, which provide protection operations and generate output signals. The logic processors also have a part in the overall protection arrangement. The output signals are communicated back to the power system assemblies for local control and protection thereof and to SCADA systems for remote control thereof. If the control panel have electronic meter with optical port/RS232 port it can be connected to SCADA computer through serial data transmission port with mux/demux.

The Software
The complete engineering and SCADA development is through a single software running on Windows. The software has unlimited tags, trends, graphical displays and has a built in Sequence - of - Events recording (SOE), which is very essential for fault diagnosis. The data such as KWH, KVA, KW, FREQ, VOLTAGES, LOAD CURRENT, KVAR etc are displayed on Excel Spread sheet. The data can be stored and displayed on the intervals as desired (instantaneous, real-time, every 15 minutes, half hourly, hourly, daily etc).Different curves such as voltage profile , load duration are also displayed. The SCADA Software will be linked with EMS/RMS software so that the system is more versatile.