Cascade Protection with Transient Voltage Surge Suppressors (TVSS) in Variable Speed Drive for Electro-Submergible Pumps

Every year in the BOSCAN oil fields, operated by Chevron, there are significant losses of oil production, due to damages found in electronic components mainly after severe electrical storms. The variable speed drives which are feeding the electro-submergible pumps are found to be most susceptible to failures of this nature. With the purpose of decreasing these failures, we considered the IEEE approach to facility protection and the potential application for variable speed drives, doing a series installation of transient voltage surge suppressors (TVSS) at different key points inside the drives. The cascade scheme for the protection of variable speed drives was devised, performed and validated in laboratory tests performed in the USA. This cascade protection scheme is currently being implemented and monitored in sixty wells of the BOSCAN field. This paper documents the criteria considered, the methodology implemented and the tests performed to validate cascade protection for variable speed drives