Background
Power system is the important component of rail transit operation, so the high-reliability is required. Rail train apply to electrical system is based on 3rd track technology of high voltage circuit. Deploy traction substation power supply for 3rd track, vehicle-mounted devices and service devices. The power system equipped with various intelligent monitoring and emergency shutdown system, maximum decrease the effect of emergency, enable power supply reliable and continuous. 
Requirements
Industrial design, equipment operating resist rugged surrounding of strong electromagnetic interference
Efficient, reliable network redundant backbone transmission system
Quick backbone looped network couple topology with sub looped network
Precise power monitoring control system, power supply to train and vehicle-mounted devices continuously
The abilities of extra long distance transmission and extra high compatibility
All equipments meet with the international management standard, compatible to all levels management control platform
Solution
Deploy IS2000 and IS3000 GE Ethernet switches on traction substation, to connect with various protection relays and BUS equipment, for status data collection. According to the different requirements of operators, divide different VLAN for transformer substation, the network of neighbor transformer substation backup path each other, using GE fiber ports to form a protection ring, top-speed link recovery technology is supported, recovery time≤ 20ms, thus, enhance the uninterrupted network of data transmission, improved the reliability of network power.
Benefits
Low power consumption, fan-less, maintenance is cost effective
4K VLAN configuration, meet the requirement of traction substations extensively
Extra long distance transmission, single node supports 80KM transmission distance, not limited by distance
Abundant looped redundant protocols of STP/RSTP/MSTP, ERPS, EAPS, etc.
Recovery time≤20ms
All equipments meet with the IEC61850-3 standard
Hardware broadcast storm resistance, under-layer network attack prevention