Digital substations

Until now, most substation automation projects have focused on the IEC 61850-8.1 station bus. However, there is growing interest in its companion standard IEC 61850-9-2, which governs process bus communication. The process bus standard enables current and voltage measurements to be transmitted to protection and control devices via a fibre-optic communication network. It represents the opportunity to make significant reductions in copper cabling and improve safety.
The process bus also supports the integration of non-conventional instru­ment transformers (NCITs). This leads to improvements in performance and also reduces cost and footprint. A further benefit is that NCITs improve safety by eliminating the risk of voltage hazards that can arise in conventional instrument transformer circuits.

In 2012, ABB completed the first fully compliant commercial installation of IEC 61850-9-2 process bus technology for Australian utility Powerlink. The installation has delivered advanced automation at the Loganlea substation, a key substation serving south east Queensland. The project has enhanced grid availability and reliability in the fast-growing region, which includes the city of Brisbane.
Digitisation of substation automation is important for grid operators. Broadly speaking, its benefits are improved security and greater levels of grid reliability. ABB has developed its hardware and software solutions for operators keen to achieve the benefits of substation automation and ensure interoperability with existing assets.
Products include the SAM600, a stand-alone merging unit and SDM600, a software solution for system data management as well as the Relion 670 series 2.0 IEDs, which are the newest members of ABB’s family of protection and control devices, and the RTU520, the latest Remote Terminal Unit in the RTU500 family of network monitoring and control devices.
Interoperability and ease of configuration are central to all of the elements of ABB’s approach to digital substations. They also address the key security requirements of multi-access substation automation systems.
SAM600 merging unit
By installing a merging unit, operators can integrate their existing instrument transformers into digital IEC 61850-9-2 process bus substation automation, protection and control systems.
Being a stand-alone unit, installing a SAM600 causes minimal disruption to substation operation and allows step-by-step upgrades towards full digitisation.
The SAM600 is such a merging unit. It digitises electrical signals so that they can be passed over Ethernet and fibre optic channels. This removes the need for copper cabling and its service and maintenance risks, and improves safety. It also enables robust, fast and responsive messaging.
Because existing sensors can be integrated into modern digital systems, the SAM600 can bridge the gap between analogue and digital signalling, avoiding the need to replace existing sensors.
The unit can ensure a future-proof installation that takes advantage of enhanced tools for engineering and testing, such as ABB’s IET600 system configuration tool and ITT600 SA Explorer for simple and efficient testing.
SDM600 data management software
Acting as a cybernetic office manager, SDM600 manages and monitors the network and its users. The software has a unified user interface and restricts users’ access to systems and equipment by checking the credentials of all visitors and giving access only to approved users.
It also logs IED disturbances using IEC 61850-8-1 and creates comprehensive status reports to identify trends in use.
Lastly, it ensures that software and firmware on every IED in the system is tracked and that updates are properly distributed. By cascading updates to other SDM600s in a system, even the largest network can be comprehensively updated from a single interface.
Relion 670 series 2.0
The latest member of ABB’s family of Relion protection and control relays is the Relion 670 series 2.0. It offers faster and more accurate performance than previous generations of the product.
A unique set of monitoring functions ensure protection and control in transmission systems and have been certified by independent laboratories as being fully compliant with both editions of the IEC 61850 standard.
The new RTU520 offers simple and cost-efficient solutions for distribution monitoring and control. DIN rail input / output modules can be connected to meet a wide range of applications.
ABB’s RTU500 series also provides a comprehensive switch portfolio in the field of Ethernet communication. This enables customers to mix different types of media like fibre-optic and two-wire copper cables (SHDSL – symmetrical high-speed digital subscriber line) in one network.

SAM600 module