Geomagnetically Induced Current Analysis in Malaysian Power Transmission System

Abstract

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 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 now. 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. The applied geoelectric fields were calculated based on benchmark value for 1 in 100 years of GMD events. Then we disconnected the 132 kV low voltage systems from the network model to investigate their 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 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.INDEX TERMS Geomagnetically induced current, geomagnetic disturbances, space weather, energy, high voltage transformers, Malaysian power system.

Analysis of Large Geomagnetically Induced Currents During the 7–8 September 2017 Storm: Geoelectric Field Mapping

“…Earth conductivity varies in all directions, however, the biggest variation of conductivity is with the depth (Boteler & Pirjola, 2019). Therefore, Earth is often represented by a 1‐D model (e.g., Boteler & Pirjola, 2019; Khurshid et al., 2020), in the frame of which we have N layers, each specified by conductivity σ n and thickness l n ( n = 1, …, N ). Then, layered case of the transfer function K (in the frequency domain f ) is expressed by the following recursive formula (Boteler & Pirjola, 2019; Weaver, 1994): $$${K}_{n}={\eta }_{n}\frac{{K}_{n+1}\left(1+{\mathrm{e}}^{-2{k}_{n}{l}_{n}}\right)+{\eta }_{n}\left(1-{\mathrm{e}}^{-2{k}_{n}{l}_{n}}\right)}{{K}_{n+1}\left(1-{\mathrm{e}}^{-2{k}_{n}{l}_{n}}\right)+{\eta }_{n}\left(1+{\mathrm{e}}^{-2{k}_{n}{l}_{n}}\right)}$$$ where K n is the ratio of E to B at the top surface of layer n , while K n +1 at the top surface of the underlying layer n + 1, $${\eta }_{n}=\frac{i2\pi f}{{k}_{n}}$$, $${k}_{n}=\sqrt{i2\pi f{\mu }_{0}{\sigma }_{n}}$$ and μ 0 = 4 π 10 −7 Hm −1 (Boteler et al., 2019).…”

“…Earth conductivity varies in all directions, however, the biggest variation of conductivity is with the depth . Therefore, Earth is often represented by a 1-D model (e.g., Khurshid et al, 2020), in the frame of which we have N layers, each specified by conductivity σ n and thickness l n (n = 1, …, N). Then, layered case of the transfer function K (in the frequency domain f) is expressed by the following recursive formula Weaver, 1994):…”

Analysis of Large Geomagnetically Induced Currents During the 7-8 September 2017 Storm: Geoelectric Field Mapping

“…Therefore, Earth is often represented by a 1-D model (e.g. Khurshid et al, 2020), in the frame of which we have N layers, each specified by conductivity σ n and thickness l n (n = 1, ..., N ). Then, layered case of the transfer function K (in the frequency domain f ) is expressed by the following recursive formula (Weaver, 1994;:…”

Impact of Geomagnetically Induced Current on Power Grid Resiliency Under Extreme Geomagnetic Disturbance

“…This asymmetrical current and the reactive power losses may result in hotspots in the transformer, relay misoperation, and tripping static var compensator (SVC), turning to permanent transformer damage or system blackout. The review of previous studies has shown that GMD effects can extend to power grids located in low latitudes as well and are not limited to high and mid-latitudes [10]. Therefore, we have maa de few GIC analyses on the power network in Malaysia since it is located close to the equatorial electrojet (EEJ) [9,11,12].…”

“…There are a few types of disturbances that drive geomagnetic storms, such as coronal mass ejection (CME), corotating interaction regions (CIRs), and interplanetary shocks [2,3]. The geomagnetic field variations create surface geoelectric electric fields and cause low frequency (0.001-1 Hz) geomagnetically induced currents (GICs) flow into grounded technological conductors [4,5] such as oil and gas pipelines, power networks, and railway [6], as illustrated in Fig. 1 FIGURE 1.…”