The multi-vendor based transformer protection scheme for transmission network

Abstract

The transformer operates under different voltage levels, requiring much better safety. Several faults can occur, such as over-current due to overloads and incipient faults, winding faults, external short circuits, and terminal (internal) faults. There is a need for careful attention to any transformer fault, as some can cause hazardous situations. A transformer protection device offers creative protection, control, and monitoring solutions. Instrument transformers scale high current or voltage values into small, uniform values that are simple to manage for protective relays and measuring instruments. The instrument transformers usually remain in operation for several years and are replaced only when a mechanical failure occurs or physical life has expired. However, substation protection and control systems have recently changed more frequently, predominantly electronic and computer-based systems. However, incorporating new technologies can introduce challenges, especially when certain IED vendors encounter compatibility issues in their communication capabilities. There is only one way to solve this issue on the distribution and transmission network systems to deploy new technology, such as one standard that will be able to interface different vendors together, the bay process bus, and Standard Protocol IEC 61850. The standard of the IEC 61850 defined the communication networks in substations that will bring interoperable systems and flexible architectures to the substation automation domain. This research focuses on the transformer's current differential protection scheme and investigates the IEC61850 standard-based communication interoperability between two different IED vendors for transformer protection. It also focuses on improving the transformer's operation speed and increasing the operational flexibility, reliability, and stability of a protection scheme for internal and external faults. The research will use the modified IEEE Nine-Bus system to develop and implement a method of testing the multi-vendor IED based on Hardware-In-Loop (HIL) configuration with the RTDS. Different software environments were used for developing and implementing a current differential protection scheme, and the performance of various types of faults was analysed. The utilization of the IEC 61850 standard based on the current differential protection scheme is developed to achieve interoperability GOOSE between the IEDs. Speed and reliability can be enhanced by using the standard GOOSE message applications for the Transformer Protection Relay System using the IEC61850 standard.