Higher I2t stress on equipment due to increased penetration of Distributed Generation

Increased penetration of Distributed Generation (DG) raises the total I²t levels on the power distribution network. Increased level of I²t is directly related to the stress levels impressed on the equipment during short circuit faults. In this paper, the definition and significance of I²t as it relates to increased stress level of equipment are explained. It is reconfirmed through simulations that increased penetration of DG leads to higher levels of total I²t at every fault location. It is shown that I²t supplied by the DG rises with higher penetration levels, confirming previous findings. The results also indicate that I²t supplied by the substation decreases which contradicts previous research. Four types of short circuit faults, including 3Phase, Line to Line(L-L), Line to Line to Ground(L-L-G) and Single Line to Ground(1L-G) faults are simulated on the IEEE 34-node test feeder, modified with 24 buses using two different programs known as Electrical Transient and Analysis Program (ETAP^®) and Advanced Systems for Power Engineering (ASPEN^®). Simulation data from both programs indicating higher confidence in accuracy due to close agreement between the results has been presented.