Testing platform of the project 'Substation of the Future' installed at the Monte da Pedra Switching Station
Within the scope of the 'Substation of the Future' project, developed by R&D Nester in collaboration with REN, a testing platform was installed at the Monte da Pedra Switching Station, with the objective of validating on-site the new architecture for protection, automation and control (PAC) systems developed in the mentioned project.
During an estimated period of nine months, this platform will work in parallel with the PAC system in service in this infrastructure of the Portuguese Transmission Grid, which will allow evaluating its performance in a comparative way.
In this new architecture, supported by the IEC 61850 communication standard, the so-called "process bus" was considered, that is, there are IEDs (intelligent electronic devices) close to the primary equipment (circuit breakers, disconnectors and instrument transformers), placed in the switching station switchyard.
For this purpose, cubicles suitable for outdoor installation were selected, where the following process IEDs gave been placed:
- CBC, Circuit Breaker Controllers: is the interface to the CB, for positions, signals and commands, also performing the synchronism check function and bay unit of the circuit breaker failure protection function.
- IUDS, Intelligent Units for Disconnector Switch: is the interface to the disconnector switches, for positions and commands.
- Merging units: convert currents and voltages from instrument transformers into sampled values that are then transmitted over the communication network.
The bay level IEDs (distance protection function) and the station level IEDs (differential bus protection function, local human-machine interface - HMI - and gateway to the remote SCADA) have been placed in the control building.
For security reasons, the platform will not issue commands to the power system. In evaluating the performance of the platform, the event lists generated by the local HMI and gateway will be used.
In addition to the new (fully digital) architecture, a 'hardwired' solution was also implemented for the 103/104 bay, which consists of two redundant units that implement all protection, automation and control functions, however without a process bus.
The objective is to use this architecture in refurbishments of the PAC system, in which the primary equipment as well as the copper cables, which connect it to the PAC system, are kept.
The monitoring of the platform can, largely, be carried out remotely, by the project team, at the facilities of R&D Nester, in Sacavém, through the established remote access.
Among the advantages of the developed architecture, it can be mentioned the simplification of the installation of the PAC system in the substations (replacement of copper cables by optical fibre), the possibility of combined use of devices from various manufacturers (interoperability) and the existence of redundancy also for the control functions (not only for protection functions).
This project will allow to test and validate the developed architecture, thus contributing to the digitalization of the power grid and the creation of a more efficient system.