Geomagnetically induced current analysis in Malaysian power system

• Published in: IEEE access 2022, p.1-1
• Main Authors: Khurshid, Z. M., Ab Aziz, N. F., Rhazali, Z. A., Ab Kadir, M. Z. A.
• Format: Article
• Language: English
• Subjects: Circuit faults; Conductivity; Earth; Geomagnetic Disturbances; Geomagnetically Induced Current; Geomagnetism; High Voltage Transformers; High-voltage techniques; Malaysian Power Network; Power grids; Power systems; Power transformers; PSCAD/EMTDC; Space Weather; Substations; Windings
• ISSN: 2169-3536
• DOI: 10.1109/ACCESS.2022.3215266

For many decades, Geomagnetically Induced Current (GIC) has posed a significant risk over the electrical power grid infrastructures worldwide. The phenomenon occurs due to geomagnetic disturbance (GMD) and related space weather events arising from solar activity. It represents a potential hazard to the secure and safe operation of electrical power grids by causing half-cycle saturation of grounded High Voltage (HV) power transformers, relay misoperation, and increased reactive power demand in the power systems. Previous studies have shown that the occurrence of intense GIC is not limited to high and mid-latitude regions, but powerful space weather events can also result in intense GIC in power systems located in lower geographic latitudes. This study aims to estimate GIC and investigate its impacts on a Malaysian power grid. A network model of the grid was constructed by using the Power System Simulator for Engineering (PSS/E). This represents the first attempt to study GICs in south-eastern Asian power grids since a region is considered to have low GIC risk up to time. During the analysis, firstly, we exposed the entire power network which includes 500 kV, 275 kV, and 132 kV system voltages to different geoelectric field strengths in the 0-180° directions and calculated GIC and reactive power losses across the system for each direction. The applied geoelectric fields were calculated based on benchmark value for 1 in 100 years of GMD events with respect to different earth conductivity models. Then we disconnected the 132 kV systems from the network model since it has a higher resistance value and we repeated the calculation to investigate its influence on the calculated GICs. The results demonstrated that the most vulnerable substations to GMD events and experienced large GICs were those located in the middle and edge of the Malaysian power network. The maximum GIC was recorded at substation 22 with the value of 44.58 A due to the peak electric field of 1.2 V/km at 100° field direction. Also, the results showed that the calculated GICs slightly increased when 132 kV systems were removed from the power network, especially at the substations directly connected to these systems.