
Centralised automation systems play a key role in managing the operational costs of power distribution utilities. These systems, based on information and communication technologies, help utilities minimise human interference in operations, improve network asset performance and maintenance, and provide centralised control and visibility for the top management. Only a few utilities have introduced these systems so far. The experience and the benefits realised can encourage others to adopt them.
MIDAS
One of Delhi’s power distribution companies, BSES Yamuna Power Limited (BYPL) has developed and introduced the Modular Integrated Distribution Automation System (MIDAS) for its licensed power distribution area. MIDAS contributes towards comprehensive monitoring of BYPL’s distribution network. This includes functions such as condition monitoring of key assets like transformers, energy meter data and fault detection. Through data analytics, the system enables predictive monitoring of assets to identify and fix the faults in a timely and efficient manner.
A key tool in MIDAS is the Smart Substation Management System (SSMS), which has components such as feeder remote terminal units, sensors, fault passage indicators, modems and a web-based application to gather and display substation data. The key features of SSMS are condition monitoring, meter data management, predictive maintenance, and automatic notification, among others.
MIDAS was specifically designed for the 11 kV/415 V distribution substation level on BYPL’s network. This was aimed at minimising the network downtime, which is largely attributed to transformers in the low tension network. The expectations are that MIDAS will be able to reduce downtime by 85-90 per cent. BYPL tested MIDAS at the 11 kV level in over 20 transformers. It has already been deployed on BYPL’s 25 substations. For BYPL, the next step will be to integrate MIDAS with other IT-based platforms – enterprise resource planning (ERP), the geographic information system (GIS) and the outage management system (OMS).
GSAS
Tata Power Delhi Distribution Limited (TPDDL), a joint venture between Tata Power Company Limited and the Delhi government, has deployed the Grid Station Automation System (GSAS) on its network. GSAS serves as a tool to collect and analyse data collected through the supervisory control and data acquisition (SCADA) system, perform remote relay maintenance, monitor equipment condition through data analysis, etc.
The centralised control and monitoring of grid stations, enabled by GSAS, has helped TPDDL optimise human resource deployment. GSAS and the SCADA-based energy management system have led to significant improvements in reliability of power supply as all load management decisions are based on the real-time information from the systems. Efficient load management has also resulted in savings by minimising grid overdrawal. As of 2012-13, all 61 grid substations in the company’s network were automated and unmanned. GSAS fits in TPDDL’s overall distribution automation plan, which is being implemented in a phased manner. The first phase of the distribution automation system was implemented in 2010-11, to monitor and control the 11 kV network. It has helped reduce downtime of the 11 kV network through online identification of faults and restoration of power supply through automated switching. The system has also helped in the selection of optimum feeder configuration, thereby reducing technical losses. The second phase of distribution automation is being implemented.
System integration
To realise the full potential of distribution automation systems, utilities have to integrate stand-alone IT-based applications and solutions. Examples of successful deployment of IT solutions show that key systems such as ERP, OMS and GIS are integrated to ensure end-to-end automation of operations. In this context, OMS is a key IT-based solution which has been utilised for ensuring an integrated approach to network and outage management.
OMS helps utilities manage outages through an integrated platform of various systems and processes related to power supply. For instance, SCADA and DMS integration enables improved response to outages in the case of an event associated with SCADA-monitored devices. Its integration with GIS provides a list of affected customers while an integrated ERP and customer relationship management system ensures updated customer records.
The evolving smart grid framework in the power sector, for which pilot projects are being implemented, is likely to accelerate the adoption of integrated solutions for automation in the distribution segment. A total of 14 smart grid pilot projects based on automated metering infrastructure (AMI) are under way. The combination of AMI and distribution automation solutions is expected to provide significant scope in key functionalities of load profiling, asset management, and integration of distributed generation sources in power supply. Further, integrated AMI and distribution automation systems can strengthen the business case for upcoming smart grid projects in the country.