Cooling towers are a critical asset to most power, petrochemical and oil and gas industries. In order to optimize performance and to save energy, large diameter, low speed cooling towers are equipped with Variable Speed Drives (VSD), allowing the cooling tower to run at the highest possible efficiency. Due to the construction, these large diameter cooling towers have to cope with large forces in their construction and high stress factors in their components and joints. Fatigue is therefore a serious risk for these type of cooling towers.
This application note describes the effect of VSD on vibration and trip levels on monitoring systems and how we manage this.