IIT Madras develops a technique to measure the level of pollution deposit
Researchers at the Indian Institute of Technology, Madras (IIT Madras) have developed a technique to identify the level of pollution deposition in power transmission networks. The IIT Madras research team plans to contact NTPC, Power Grid and other utilities to demonstrate this technology and its use in the actual power system grid, a statement from IIT Madras said.
According to the IIT Madras statement, the pollution-related electrical flashover occurs under working conditions and can lead to blackouts and system collapse. Cleaning the polluted insulator under operating conditions appears to be the surefire way to solve the problem, he added.
The reliability of a power supply system, the statement added, depends largely on the performance of the electrical insulation. The external insulation of transmission lines stretching over a few hundred thousand kilometers and substation equipment, in addition to electrical, thermal and mechanical constraints, are subject to environmental pollution.
“However, due to the high operating voltages and the immense spatial extent of the power transmission system, it would be essential to determine the level of pollution deposition and the type of pollutant before such a gigantic exercise can be planned.” , indicates the press release.
A laser-induced fracture spectroscopy (LIBS) based solution has been developed by the research groups of Prof. R Sarathi, Department of Electrical Engineering, IIT Madras, and Prof. NJ Vasa, Department of Engineering Design, IIT Madras.
Currently, by projecting a laser beam at a distance of 40 meters, researchers can identify the constituents of pollution deposits, while efforts are underway to extend this distance to 100 m. This would make it possible to assess the pollution layer on the insulators of transmission lines and wind turbines either from the ground or from a drone.
This work was financially supported under the National Perspective Plan of the Ministry of Energy, Government of India through the Central Power Research Institute (CPRI), Bengaluru.
Elaborating on the important results of this research, Prof Sarathi said: “The presence of salts and other pollutant deposits on insulating materials has been successfully identified using LIBS analysis. The level of pollution on the insulating material was identified using the proposed linear relationship between the normalized intensity ratio of the LIBS spectra and the level of equivalent salt deposition density (ESDD).
To determine the constituents and the amount of pollution, the deposit on the insulators is collected and then the evaluation of the equivalent density of salt deposition (ESDD) and non-soluble material deposition density (NSDD) is carried out. There are also attempts to measure the leakage current through the insulator to monitor the severity of the pollution. These are quite heavy and expensive, according to the IIT Madras statement.
Using this efficient technique, the researchers said, the level of pollution on transmission line insulators and wind turbines can be identified at any remote location. This technique could allow the power grid community to have online monitoring of the condition of transmission line insulators.