Testing and measurement (T&M) of power equipment is vital for maintaining efficient and optimal operation of equipment and a robust power system. Besides, it plays a vital role in ensuring 24×7 power supply in the country. Power systems need to be tested and maintained at regular intervals, as the breakdown of any one of their components has the potential to trigger a grid collapse. Meanwhile, in the power generation segment, T&M solutions could be useful for complying with the revised emission norms as well as for efficient combustion. Apart from this, with the Atmanirbhar Bharat Abhiyan promoting domestic manufacturing of power equipment, testing facilities are expected to expand in the coming years.
In the power generation segment, complying with the revised emission norms and enhancing the operational efficiency of power generation are the top priorities of the utilities. They are increasingly deploying T&M solutions, comprising sensors and analysers, to track plant parameters. Continuous emission monitoring systems and predictive emission monitoring systems are gaining traction for their use in keeping track of emission levels and taking swift corrective measures. In order to ensure efficient combustion, T&M solutions are being deployed for careful monitoring of the quality of water and steam used in the feed water, and for finding the right air-fuel mix for combustion. Moreover, the central government has set a target of 450 GW of renewable energy capacity by 2030, which is expected to create significant demand for T&M of renewable energy equipment including solar cells, photovoltaic modules and wind turbine generators in the coming years.
In the transmission and distribution (T&D) segment, T&M of equipment such as transformers, conductors and electricity meters is vital for ensuring 24×7 quality power supply. T&M is crucial for transmission utilities, especially as they move to higher voltages and deploy high-value equipment such as transformers, rectifiers and high voltage direct current (HVDC) systems. For instance, Power Grid Corporation of India Limited (Powergrid) is implementing 1,200 kV ultra high voltage (UHV) AC and ±800 kV HVDC projects, while state transmission utilities such as Maharashtra State Electricity Transmission Company Limited, Rajasthan Rajya Vidyut Prasaran Nigam Limited and Uttar Pradesh Power Transmission Corporation Limited have progressed to the 765 kV level. Many discoms are taking steps to implement high voltage distribution systems to improve the high tension-low tension ratio in their networks.
T&M of smart meters is also an emerging focus area in the distribution segment, as accurate measurement of energy is crucial both for consumers and service providers. With the government’s mandate to replace all conventional meters with prepaid smart meters in the next three years, the need for laboratories to test smart meters is expected to increase significantly. In addition, T&M of electric vehicle chargers and batteries, microgrids, and underground cables is likely to be in greater demand in the coming years.
The T&M market comprises original equipment manufacturers, vendors and third-party testing agencies. Many equipment manufacturers and utilities have set up advanced testing facilities for ultra UHV/extra high voltage (EHV) systems, transmission towers, cables, meters and advanced switchgear. The National Accreditation Board for Testing and Calibration Laboratories (NABL)-accredited labs such as the Central Power Research Institute (CPRI) and the Electrical Research and Development Association (ERDA) regularly conduct testing and certification of T&D equipment. They perform several activities, including the evaluation of EHV/UHV equipment; high power short circuit testing of transformers, circuit breakers and other T&D equipment; power system studies; and transmission line tower and accessories testing.
For the testing of high voltage equipment, NTPC Limited, NHPC Limited, Powergrid, the Damodar Valley Corporation and CPRI have together set up the National High Power Test Laboratory (NHPTL) at Bina, Madhya Pradesh. As the laboratory provides transformer testing (short-circuit testing) facilities within the country, these companies no longer have to send large power transformers (especially 100 MVA and above) to overseas testing laboratories such as KEMA in the Netherlands and CESI in Italy. In November 2020, BHEL successfully manufactured and tested (short circuit) India’s highest rating auto transformer at NHPTL. The 500 MVA 400/ 220/33 kV auto transformer was designed and manufactured at BHEL’s Bhopal plant for Uttar Pradesh Power Transmission Corporation Limited. These high rating transformers play a crucial role in bulk power transmission to load centres and bigger cities.
With regard to the new and upcoming testing facilities, CPRI is setting up a regional testing laboratory at Nashik, Maharashtra. Manufacturers in the western region will be greatly benefited by this, as it will enable them to test their products close to their manufacturing units. This will reduce turnaround times and overhead costs. Apart from this, in September 2020, the ERDA announced that it is expanding its switchgear temperature rise facility to serve customers more expeditiously. The development of an additional switchgear testing bay will cater to the ERDA’s continuously growing pool of valued customers, as well as enhanced testing requirements. With this, ERDA will be able to serve customers more promptly and diligently. Moreover, as a part of a scheme titled “Manufacturing Zones under Atmanirbhar Bharat Package”, the Ministry of Power (MoP) will launch a domestic manufacturing programme for critical power and renewable energy equipment at an outlay of Rs 15 billion in the coming financial year. In these manufacturing zones, the equipment testing facility will be set up by CPRI for power equipment, and by the National Institute of Solar Energy and National Institute of Wind Energy for renewable equipment.
MoP’s order for testing of imported equipment: In July 2020, the MoP notified an order issuing directions to protect the security, integrity and reliability of strategically important critical power supply systems and networks in the country. According to the order, all equipment, components and parts imported for use in the power supply system and network will be tested in the country to check for any kind of embedded malware/trojans/cyberthreats, as well as for adherence to Indian standards. All such testing will be done in certified laboratories designated by the MoP. The order will apply to any item imported for end use, or to be used as a component or raw material in equipment used in the power supply system or any activity directly or indirectly related to the power supply system.
CEA’s guidelines on validity of type tests for transmission equipment: In view of the increasing grievances of manufacturers regarding the validity of type tests mandated by the utilities, the Central Electricity Authority (CEA) has released the “Guidelines for the validity period of type test(s) conducted on major electrical equipment in power transmission”, which standardises the duration of validity of type tests conducted on transmission system equipment. The guidelines state that the type tests conducted on the equipment shall remain valid and acceptable provided no major change is introduced in the basic design, technology, material and mechanical construction, etc., for a period varying from five to ten years across different equipment categories. For instance, the validity period of the type tests of power transformers, distribution transformers (33 kV and below), and energy meters (including smart meters and availability-based tariff meters) is five years; for low voltage and medium voltage switchgear, gas-insulated and hybrid switchgear, and cables and associated joints, it is 10 years; and for high temperature superconductors, high temperature low sag conductors, transmission line insulator hardware fittings, and accessories for conductors and ground wires, it is seven years.
Meter testing norms under Electricity (Rights of Consumers) Rules, 2020: The MoP has notified rules for the rights of electricity consumers, including rules for addressing a faulty meter. The rules state that the testing of meters will be done by the distribution licensee within a period, as may be specified by the state electricity regulatory commission, not exceeding 30 days, of the receipt of a complaint from a consumer about their meter readings. At the time of reporting, there are no provisions for charging consumers any fees for the tests; however, if a meter is found to be defective or burnt due to reasons attributable to the consumer, the consumer will bear the cost of the new meter as well as the test fee. In case a meter is found to be inaccurate during testing, the excess or deficit charges would be adjusted in the subsequent bills as specified by the commission. If a consumer disputes the test results, the meter will be tested at a third-party testing facility selected by the consumer from the list of third-party testing agencies approved by the commission.
Issues and the way forward
Some of the key challenges in the testing of power equipment are the long testing time at NABL-accredited laboratories and the limited availability of laboratories such as CPRI/ERDA. Besides, there have been instances of errors at NABL-accredited testing laboratories, even in sensitive cases of testing such as sound transmission class rating tests and accuracy tests, primarily due to overcrowding at the existing NABL-accredited testing laboratories. To resolve this issue, utilities need to upgrade the testing systems in all their laboratories with state-of-the-art technology, and secure NABL accreditation for all their labs. Furthermore, reliable and world-class T&M units need to be developed through technology sharing with foreign players. A star rating system can also be developed for independent test laboratories, as independent testing further validates quality, safety and reliability.