Cutting-edge technology, necessary changes to smart grid operations

Today, with the rapid development of technology, the most advanced equipment on the high voltage grid has been researched by manufacturers to develop new solutions to optimize the construction, operation and maintenance. device. In Vietnam, the current transformer stations are operating mainly type AIS stations which are installed and operated outdoors with a large station construction area. In addition, a number of GIS transformer stations have been commissioned in the operation house, small area for the construction of the station with high initial investment costs.

Hybrid IS technology improves grid efficiency

Air Insulated Substation (AIS): Most devices on the high voltage grid are separate components that carry out different tasks and are linked together through a conductor. The combination of equipment from switchgear, measurement and wiring creates an interruption in one substation. These devices use the air gap as the medium between the phase and the phase. And this is the most common type of substation used on the current 110kV grid, where devices in a high voltage enclosure can include circuit breakers, isolators, transformers, transformers.

The current AIS transformer station

Gas Insulated Substation (GIS): The secondary devices and conductor connecting the compartments are placed in sealed enclosures containing SF6 insulating gas at a certain pressure. SF6 gas is used as an insulating material between charged phases, between charged equipment and soil. And for the GIS system, there is another important point: the SF6 gas monitoring system for monitoring alarm integration, automatic fault removal and locking in case of gas leakage from the system. the system.

To date, a new type of transformer substation has been introduced in electrical systems in countries around the world and in Southeast Asia, the Hybrid Insulated (Hybrid IS) substation. This is a substation that is defined as hybrid between 2 AIS and GIS technologies. With the use of cutting elements placed in an SF6 gas-insulated environment, and on top of that the integrated measuring devices form a single block. Only electric wires connected between compartments are placed outside and use conventional gas insulation.

GIS transformer station

Advantages of Hybrid IS versus AIS and GIS:
It helps to reduce the installation space by up to 50% more than the AIS station. Specifically 01 to prevent the line 110 kV will have a length of about 12-15m, the use of Compact Switchgear will reduce the length to about 3-4m. This helps to invest in the construction of transformer stations in urban areas with modest land area. In addition, it is suitable for the new widened investment with the smallest expansion area. Reduce the costs of construction of foundation equipment compared to AIS stations or build houses to operate as GIS stations.
Reduced labor due to reduced workload such as transportation of materials, installation of support posts, installation of each device, mechanical adjustment. Reduced construction time at the site. The most compact Compact Switchgear devices fit in with the new dual-system integration technologies in the future.
Defect:
At present, when the Compact Switchgear is introduced into operation on the grid, the modifications to the design and maintenance procedures of this type of equipment are underway. Since the closure objects are housed in a closed chamber, mechanical closure can not be observed, so it is only possible to monitor the mechanical signals and indications outside the equipment. Accompanying this, is the inability to isolate each element for repair or replacement in the event of a malfunction.
By leveraging the advantages of AIS and GIS technology, the Hybrid IS substation promises to be widely used in power systems to increase the reliability of power supply and smart grid construction. and reduce investment costs.