New energy supply challenges

Energy supply is crucial in modern industrial societies. Flexible network coverage is needed to cope with the diverse demands of private households, industries and public institutions. Incidents result in high costs and may have severe consequences. To guarantee regular and highly efficient energy coverage, rapidly resolving irregularities in the high-voltage grid is a top priority. Immediate measures can only be taken when the fault message is analysed directly after its receipt. Transient Fault Recorders hence have a key function in guaranteeing a solid energy supply.

iba components

In 2001, Siemens Energy was looking for a possibility to record fast transient processes with high time resolution and to rapidly analyse the measurement records in case of a failure in the control system. Many iba competitors could analyse the data in case of a failure only several minutes after an event had occurred. The iba TFR provided data within just a fraction of a second. Another important feature is the rapid data acquisition with high-resolution from 10 to 20KSamples/s. Analogue and digital data can be acquired simultaneously. The data are processed in a high resolution and in a synchronous way.

These were the decisive advantages when it came to the 'Estlink' project (Finland/Estonia), for which of Siemens Energy is responsible as general contractor for the submarine energy transport over 145 km from Finland to Estonia. This places high requirements on Siemens control technology: for example, over a length of 500m, fast signals have to be connected from an existing AC distribution station to the new control system. So called "Runups” and "Runbacks” can trigger changes in power transfer, like e.g. during a load shedding in the grid. In this case, the power needs to be reduced very rapidly from 400 MW to 100 MW.

Realtime values

The TFR system is based on the ibaPDA-V6 data acquisition software. The direct acquisition of signals from current and voltage converters is realised either with the ibaPADU-16-M analogue/digital converter module or with the new modular ibaPADU-S technology. Alarm and status messages are transferred to other systems by ibaNet750. Finally, a great number of signals from the Siemens control system SIMATIC TDC are acquired by interface cards belonging to the ibaLink device family. Due to the very good connectivity, a seamless integration into the Siemens control system was possible.

The ibaPADU-S modular system acquires and processes measured signals. With the right signal output modules, it can also be used for closed loop control applications. The system can be designed freely: on one installation rack with backplane bus, you can plug one central unit and up to four other input and output modules. With ibaPADU-S, measurement values can be processed into characteristic values while the raw data are transferred in realtime to an ibaPDA-recording system or to the control system.

Control signals

"We have had good experiences with the iba Transient Fault Recorders. So it was obvious for us to rely on iba technology also for control signals using the same well proven interfaces,” Martin Haushofer said, responsible for DC Hardware Engineering in the field of control technology in the Siemens Energy Business Unit Transmission Solutions. For applications of TFRs, in case of failures (triggers) the acquired signals are stored in the .dat format on the iba-PC and then transferred automatically via the network to an analysis computer in the control room. There, within a delay of just a few seconds, the failures can be analysed.

Today, Siemens Transmission Solutions use TFR made by iba as a standard. Says Haushofer: "We appreciate the flexibility of the iba products as well as of the entire company. The more flexible the supplier’s products can be adapted to our needs, the more efficient we can satisfy our customers' needs.”