It is essential to maintain the power factor near unity for effective utilization of the available apparent power as renewables are gaining importance in the power system. Capacitors form an important component in achieving the power factor near unity. Capacitors are being used in the ac network for reactive power compensation either in shunt or series mode. These capacitors must be evaluated for their performance to meet the requirement of various international/national standards International/ National standards for evaluation of capacitors are continuously evolving based on the application. Endurance testing is an important test to assess the performance of the capacitors for long duration application and to find the suitability for their availability in the network. The paper discusses the experience of two decades in performing Endurance testing for evaluation of capacitors used in the ac network with reference the IEC standards. Important observations in the evolution in the IEC standards for Endurance testing. Number of overvoltage cycles applied during over voltage test and duration of ageing test were also discussed in the paper.
- IEC 60871-2-1987. Shunt power capacitors for ac power systems having a rated voltage above 1000V- Endurance Testing; 1987.
- IEC 60871-2-1999. Shunt power capacitors for ac power systems having a rated voltage above 1000V – Endurance Testing; 1999.
- IEC 60871-1-2014. Shunt power capacitors for ac power systems having a rated voltage above 1000V – Part-1- General – Type Test-Over Voltage Test; 2014.
- IEC 60871-2-2014. Shunt power capacitors for ac power systems having a rated voltage above 1000V- Part-2- Endurance Testing- Ageing test; 2014.