The demand for substations is rising quickly within the nation, pushed by the enlargement of the transmission and distribution (T&D) community and the rising integration of renewable vitality. Varied authorities schemes have been formulated to strengthen and modernise the T&D community. Transmission utilities are specializing in augmenting substation capability to additional improve the community and allow larger renewable vitality integration. The Revamped Distribution Sector Scheme additionally lays emphasis on community modernisation and upgradation within the distribution section. These components are driving the demand for substations within the sector.
In an effort to meet the rising necessities, utilities are adopting new substation designs and applied sciences. They’re additionally investing in options to cut back the environmental influence of the section and deploying digital applied sciences and web of issues to facilitate automated operations, vitality administration and sensible grid operations. Renewable Watch offers an outline of the expertise tendencies within the substation market and the implications of the section on renewables uptake in India…
Forms of substations
A substation is {an electrical} system able to dealing with excessive voltage. The first job of a substation is to ship a gentle provide of electrical energy from the facility plant via the transmission system to the ultimate shopper. There are several types of substations for the environment friendly operation of the facility grid. In response to their meant use, substations may be categorised as indoor, out of doors, energy technology and converter substations. A typical substation switches from one transformer to a different with low-voltage tools.
There are several types of substations accessible available in the market. Air-insulated substations (AISs) use air to insulate varied reside elements and have historically been used for energy transmission in India. Nonetheless, with the rise in area constraints, land prices, renewable vitality and electrical automobile (EV) penetration, the emphasis is shifting in direction of substation and switchgear applied sciences that require much less area and are extra dependable. Fuel-insulated substations (GISs) have emerged as a well-liked selection as they use sulphur hexafluoride fuel, which helps cut back the gap between lively and non-active switchgear elements, leading to lowered area necessities. GIS will also be put in each indoors and outdoor. Hybrid substations are a mixture of AIS and GIS applied sciences and may be put in each indoors and outdoor, making them perfect for area and cash financial savings.
The idea of digital substations can also be gaining traction. They occupy much less area than conventional substations. Additional, sensible digital substations may be useful throughout excessive climate circumstances as a result of they will successfully reroute electrical energy to minimise the loss and injury of belongings. Given the fast uptake of renewable vitality technology, digital substations are urgently wanted. They will successfully handle load and provide whereas accounting for real-time developments, offering steady electrical energy in accordance with demand and provide dynamics. Cellular substations are additionally a typical sort of substation owing to their portability. They will simply be transported to areas with excessive electrical energy demand.
A digital substation is a vital element of the sensible grid within the energy transmission section. In a digital substation, fibre optic cables change conventional copper connections that use analogue alerts. One of many key options of a digital substation is the implementation of a course of bus based mostly on the IEC 61850 protocol. The method bus replaces hard-wired connections with communication strains, enabling the deployment of optical fibre community (ethernet-based) as an alternative of copper wiring between clever digital gadgets and varied different tools. This enables the substation’s standing and efficiency parameters to be shared in actual time via digital alerts with out sophisticated wiring. Transformers and switchgear constantly transmit knowledge over the method bus and to any upstream gadgets for defense, measurement, metering and monitoring.
Digital substations incorporate built-in info and real-time communication applied sciences, that are interfaced with course of bus and station bus structure. Digital substations primarily allow the combination of real-time knowledge and knowledge analytics into the system, facilitating extra correct decision-making, lowered downtime and enhanced diagnostics. Actual-time diagnostics, in flip, assist get rid of the necessity for troubleshooting and cut back the price and time expended on repairs and upkeep via the well timed prognosis of issues within the substation. Different intangible advantages of digital substations embrace improved productiveness and performance, larger asset reliability, substation operator security and decrease value and area necessities.
In December 2020, Energy Grid Corporation of India Restricted (Powergrid), in collaboration with Bharat Heavy Electricals Limited, efficiently commissioned India’s first indigenously developed 400 kV optical present transformer and digital substation parts on the 400/ 220 kV Bhiwadi substation. Powergrid has additionally commissioned a digital substation based mostly on IEC 61850 course of bus expertise at Malerkotla, Punjab. The expertise offers flexibility in engineering, paving the way in which for sooner commissioning, lowered downtime, enhanced diagnostics and ease in troubleshooting throughout asset administration.
Implications for renewables uptake
As per the Central Electrical energy Authority’s report on “Transmission System for Integration of over 500 GW RE Capability by 2030”, round 25,000 MW of high-voltage direct present transformation capability is predicted to be added on the interstate stage by 2030. Voltage-wise, the anticipated additions are 20,000 MW on the ±800 kV stage and 5,000 MW on the ±350 kV stage. In the meantime, alternating present substation capability of 408,575 MVA is predicted to be added by 2030, of which 274,500 MVA is predicted on the 765 kV stage and 134,075 MVA on the 400 kV stage. Total, the interstate transmission system would require an funding of about Rs 2.44 trillion.
In response to the report, roughly 33,658 MW is already accessible in current/beneath development inter-state transmission system (ISTS) substations and can be utilized for the combination of renewables. This includes 15,058 MW and 18,600 MW on the 220 kV stage and 400 kV stage, respectively. Area-wise abstract of margin accessible in ISTS sub-stations is: northern (5,250 MW), western (9,628 MW), southern (5,630 MW) and jap (13,150 MW).
India’s energy sector is witnessing important investments within the renewable vitality section, together with wind and solar energy, with the intention of mitigating carbon emissions. The growing adoption of renewables has elevated grid administration necessities. The facility generated from these so-urces is inherently inconsistent, counting on beneficial climate circumstances. If not effectively managed, the dynamic energy circulation introduced in by renewable vitality technology may pose dangers to grid stability. Moreover, utilities might face important challenges in balancing shopper provide and demand as a result of unstable nature of renewable vitality sources resembling photo voltaic and wind. The usage of distributed renewable vitality technology methods, quite a few non-linear masses, EV charging, and so on., are growing the complexity {of electrical} grid methods. This requires the event of sensible grid expertise to help utilities in managing energy demand throughout their whole distribution community, together with substations. The rising integration of renewable vitality into the grid creates a necessity for automated switchgear and substation options that present higher monitoring and management capabilities. Going ahead, renewable vitality addition requires transmission community enlargement, which is able to create demand for revolutionary substation applied sciences and allow capability enlargement of substations.
