ANALYS AV HUR ETT LOKALNÄT PÅVERKAS AV DATACENTERLASTER

Sammanfattning

This study investigated how data centers affect the operation of a local 20 kV distribution network. The aim was to analyze the impact of data centers on network operation and evaluate whether traditional methods for power quality assessment and operational monitoring are sufficient to ensure high reliability. The study also examined how components such as cables, transformers, cable terminations, and relay systems are affected by data center integration. Furthermore, the work provides recommendations for how network operators can adapt operation and monitoring in networks with data center loads. Data centers constitute a non-linear and dynamic load in the power grid, creating new challenges regarding operation, reliability, and reduced component lifetime. The work was based on a literature review combined with calculations in a simplified network model, where the effects of power quality were analyzed. In particular, the study examined how harmonic distortion affects resistance and power losses in power cables, transformers, and cable terminations, as well as how resonance phenomena may occur at harmonic frequencies. The results show that harmonics and high-frequency disturbances can lead to increased heat losses and thermal stress. In power cables, losses increase due to higher effective resistance caused by the skin effect and an increased RMS current. Transformer losses also increase in the presence of harmonics, particularly because eddy current losses rise quadratically with frequency. Cable terminations are subjected to greater stress since dielectric losses and losses in the stress grading material increase with frequency and voltage. The results indicate that the highest risk of cable termination failure occurs at higher-frequency harmonics combined with resonance phenomena that amplify the voltage.The conclusion was that connecting data centers to a local 20 kV network reduces the network’s ability to maintain stability and reliability. Harmonics generated by data centers increase losses, temperatures, and stress on transformers, cables, and cable terminations, which may shorten equipment lifetime and increase the risk of disturbances and outages.As data center integration continues to grow, improved power quality monitoring, frequency-specific analysis, and adapted dimensioning of cables, transformers, cable terminations, and protection systems will become increasingly important to ensure a reliable and robust power system.