China: ABB Delivers Communication Techology to Ningbo Metro

Image courtesy of ABB

ABB has installed substation communication technology to detect multiple faults on Line 2 of the Ningbo Metro in China. Initial results from the system demonstrate a significant improvement in the reliability and stability in the metros power supply.

Ningbo Metro Line 2 is currently in the testing phase, but is hoped to run passenger services by the end of 2015. It will have 22 stations, connecting to the Ningbo metro network and mainline rail transit system and the city airport. It will transport 1.5million commuters.

The system is the product of two years development and testing by ABB. It is based on the IEC 61850 protocol standard which supports network security and control, as well as reducing the time taken to discover and recover from faults.

The smart selective trip solution combines the company’s ZX2 40.5-kilovolt gas-insulated switchgear and REF620 relay with GOOSE-based communication technology. Generic object oriented substation events (GOOSE) is part of the IEC 61850 standard and utilises Ethernet-based object-oriented communication technology for substation automation.

In traditional setups, protection and control relays in substations were only able to communicate by hard-wired connections in linear sequence. This process was time-consuming and insufficient for dealing with multiple faults in complex metro grids. The GOOSE-enabled smart selective trip function provides these relays with peer-to-peer information sharing on demand, which enables shorter fault discovery times.

The technology is currently undergoing primary short-circuit fault simulation tests. Its success will go on to inform substation communication technology in fault detection for other metro lines around the world.