The country’s dependency on coal based thermal power stations for meeting its energy needs has resulted the environmental concern and focus its efficient and reliable operation. Out of the total installed capacity of over 330 MW, nearly 60 per cent is coal based, the majority of which comprises of domestic coal with a high ash content. While thermal power stations must ensure a secure power supply, recently efficient middle-range power operations and environmental preservation at thermal power stations are also becoming increasing important issues which have brought the need for more sophisticated operation and control. Meanwhile, in response to the changing circumstances of the electric power industry, systems must be implemented that can also meet requirements such as cost effectiveness and labor savings.
The requirement for making coal fired stations intelligent arises from the bead for highly efficient plant operation and asset management on one hand and wide scale penetration of renewable energy (solar photovoltaic and wind) into the grid which results in rapid cycling of the thermal plants, on the other hand. Ramping up or down of thermal power plants hitherto was through manual load setting or through the free governor mode of operation. With the entrance of rapidly varying renewable generation, the need for automatic load setting on the thermal plants through intelligent features arises.
As a result, there is a need for more sophisticated operation and control to keep pace with the increase in supervisory and operational control. Moreover, changes in the electric power industry such as free competition and deregulation, mean that electric power companies are becoming increasingly keen to cut construction costs, operation and maintenance costs. Against this background, there is need to developed a supervisory and control system that not only maintains the high degree of reliability developed, but also seeks to be economical, while at the same time reducing the work of operators and maintenance engineers.
A supervisory and control system that aims to deliver not only operability, reliability and maintainability, but also cost-effectiveness, while at the same time enabling labor savings in operation and maintenance. The new system has been applied to a state-of-the-art coal based thermal power station and combined-cycle power station. Through enhanced interlock, expanded automation, on-site supervisory robots and other technological innovations, the system has enabled integrated operation from the central control room and labor savings. In addition, implementation of protective functions by printed circuit board, software configured alarm system and common sensor system, the system is not only highly reliable and easy to maintain, but also economical. On-site start up operations and commercial operations results has confirmed the effectiveness of these features. SCADA is a centralized system used to supervise a complete plant and basically consists of data accessing features and controlling processes remotely. It will help to improve the overall performance and efficiency of power station and enhance useful life.