Abstract: In the medium voltage power distribution system of an offshore platform,the cargo oil pump often has unexpected trip,which affects the stability of crude oil export operation and causes security risks. After analyzing the fault,it was decided to use a new integrated protection device to replace the faulty old device. The hardware performance of the new integrated protection device was designed,including port requirements,protection function and communication compatibility. The protection parameters,logic parameters,I/O parameters and communication parameters of the integrated protection device were reconfigured by the host computer. The PLC communication program of the central control system and the comprehensive insurance communication was redesigned and programmed to solve the problem of communication compatibility. Combined with the port function of the new integrated protection device,the relay control circuit of the motor was redesigned and installed,and the replacement of the integrated protection device was completed. The implementation of this scheme provides experience and reference for the replacement of the old equipment in the oilfield power distribution system.

Key words: integrated protection device, relay control system, field bus communication, power system automation