Telecommunication needs for power utilities differ to a great extent from the requirements encountered in a carrier or an enterprise environment. Utility companies indeed have a different challenge as they need to deliver power to their customers, in an efficient way, 100% guaranteed. A reliable telecommunication network is an important building block to achieve this.
Maximising the lifetime of legacy equipment
Utility companies have built up their power grids over many decades. The lifecycle of the grid components is long. Step up transformers, protection relays or circuit breakers may well be in place for 30 years and are still running fine. The network needs to handle all this legacy equipment for quite some time.
Operational simplicity as a prerequisite
Most of the power utility personnel are engineers with multidisciplinary skills and know-how. As everything is interconnected, they need to have a thorough understanding of multiple technical aspects of the grid’s operations. The same is true for the staff in charge of the operational telecom network. They need to understand all applications supporting the grid like SCADA, protection, energy management and the impact of the operational telecom on these critical applications. Hence, they should be relieved from having to handle a highly complex telecom infrastructure. Therefore, the network must be easy to manage - making sure that all technical staff can effectively focus on their mission-critical applications. At all times!
Zero impact of environmental conditions
Power substations do not look like telco rooms or data centres. Air-conditioning: probably not. Room temperatures: unpredictable. EMC/EMI: you bet! The electro-magnetic fields that are present in the substations are significant, especially when a short circuit occurs. On this occasion the network plays a vital role. The network equipment needs to be hardened and needs to comply with the most demanding environmental standards like IEC 61850-3 and IEEE 1613.
When every bit matters
If the grid suffers a short circuit, the affected part should be taken out of service in no time. So, protection relays are installed at each end of the power transmission lines. These devices constantly monitor the current in the line and will detect any anomaly. For the grid to respond in time and in a correct manner, communication between these protection devices is of the utmost importance. This functionality is often referred to as “teleprotection”. If an anomaly is validated, the protection relay will command a circuit breaker on the line to switch off. The fault is cleared properly if both circuit breakers at the end of the line are “tripped”, i.e. have put the line out of service. All this needs to happen in milliseconds. In the case of differential protection, the delay of the data transmission has to be constant and symmetrical. These applications result in some stringent requirements in terms of network performance. If the fault isn’t cleared properly, chances are high that the fault propagates through the grid resulting in a black-out (dependability). Also, false trip signals should be avoided by all means (security). The underlying telecommunication network needs to be highly reliable and secure.
Underpin the specifics of the industry
Power utilities have developed their own way of working. They have managed to define telecom standards solely for utilities. For example, the IEEE C37.94 was drafted to interconnect “teleprotection” data over fibre optic links. Another example is the IEEE standard 1588v2 which adopted a profile specifically for power utilities for time synchronisation in the substations. Obviously, these specifics need to be supported by the network.
Since the market introduction of XTran back in 2014, more than 100 power utilities across the globe have selected the platform for a smooth transition from their SDH/SONET legacy network to packet based solution. Their testimonials provide the strongest endorsements of the market leading status of XTran for this market segment.
