Introduction

Guangzhou is the third largest city in China and the capital of Guangdong Province, southern China's largest city and a key transportation hub. With a population of eight million people in an area of over 16,000 square kilometers, it is the most populous city in the province and the third most populous metropolitan area in China. Guangzhou discovered that the reliability of Moxa's PowerTrans IEC 61850-3 Ethernet switches was perfect for its demanding smart distribution automation project. Guangzhou's power distribution system consists of a complex web of power utility network connections over several districts, with correspondingly complex wiring requirements. It was time to look at new technologies that would enable high-value, efficient and reliable operations to address the critical factors found in large-scale power distribution automation projects.

System Requirements

• High network availability to ensure proper electricity transmission over different districts 
• A cost-effective network architecture to simplify network connections over a far-ranging power distribution network 
• Reliable performance under extreme temperatures 
• Layer 3 switching capability for large scale networks

Moxa Solution

Moxa's breakthrough Turbo Chain redundancy technology dramatically simplifies the creation of multiple redundant connections over a widely dispersed power distribution network. With Turbo Chain, PowerTrans Ethernet switches can be daisy-chained together from one Ring Main Unit (RMU) to another, with each "chain" connected to the distribution substations. If a chain segment fails, the blocked path will rapidly activate within 20 milliseconds to ensure high network availability. Moxa's breakthrough Turbo Chain flexible redundancy technology frees system builders from the costly limitations of conventional ring architecture. Compared with conventional ring topology, Turbo Chain eliminates the need for kilometers of extra cable and additional Ethernet ports to form ring coupling paths. In addition, the PowerTrans PT-7828 Layer 3 Ethernet switches also support Open Shortest Path First (OSPF), which uses "link state" instead of  "hop count"  to determine the network route. Compared to Routing Information Protocol (RIP), OSPF has faster network convergence and consumes less network traffic.

Why Moxa

• Using Moxa Turbo Chain saves a significant amount on development cost, time, effort, cabling, and Ethernet ports over an extensive power distribution network. 
• Beyond the limitations of conventional redundant ring technology, Moxa's Turbo Chain addresses the challenging environment found in complex power distribution network connection and enables high network availability with its self-healing capability (recovery time < 20 ms). 
• Moxa's PowerTrans series is designed for fanless operations in a wide temperature range of -40 to 85ºC. 
• Moxa's PT-7828 Layer 3 Ethernet switches support Open Shortest Path First (OSPF) to improve traffic flow and network efficiency.