Importance of Transient Studies in Large Electrical Systems
District Cooling Plant
A District Cooling Plant (DCP) consists of a centralized energy plant that distributes chilled water through underground pipes to buildings primarily for air-conditioning, thus reducing the need of local split systems, chillers, or cooling towers.
A client requested for various transient studies to understand the impact of transients in the DCP electrical system.
Switching Transient Study
Stresses on account of multiple switching scenarios were simulated for operational and fault conditions, to validate the impact due to switching on the system insulation level. voltage dip was found to be very low due to switching during L-G earth fault. The study inferred that the transient levels were under acceptable limits.
Lightning Transient Study
Stresses in the electrical system on account of lightning surge in underground cable of incoming electrical utility of the DCP was evaluated. This study inferred that the DCP had no risk of indirect lightning surge due to the underground cable system. Additionally, the insulation levels of the equipment were verified and were found under standard limits.
Transient Grid Potential Rise (TGPR) Study
The purpose of TGPR study was to understand the transient rise in ground potential during electrical faults and lightning surges to assess the reliability of high voltage equipment during these conditions. In this study, transient stresses on the earth grid were analyzed at various points to understand if metal to metal potentials were under safe limits.
Ferro- Resonance Study
Extreme pulsating stress can be caused due to ferro Resonance in the electrical system which may breach the insulation and cause short circuit, excessive temperature rises and blowing of input fuses. This transient study was conducted to determine occurrence of ferro resonance during operating conditions. Based on the results obtained, the working conditions of the electrical network was found to be safe in assessed operating conditions.
Benefits
Transient study along with TGPR is essential for large electrical systems to understand network behaviour during fault, switching and lightning. This reduces unplanned shutdowns of electrical systems and ensures sustained performance of high value equipment as intended by removing existing anomalies through implementable corrections.
Manav Energy Power System Study experts are trained in various software to model simulate and analyse network behaviour and performance in any kind of transient conditions.
