Group for electrical measurements and signal processing

GELM

group leader

prof. Tonko Garma, PhD

associates

prof. Tomislav Kilić, PhD
prof. Goran Petrović, PhD

Group description

The research group specializes in the measurement, modeling, and diagnostics of power systems, with a particular focus on the development of advanced metrological and testing methods. Its core research activities include the development and application of power system disturbance simulators, as well as the calibration of non-sinusoidal voltages and currents to ensure measurement accuracy and the reliability of diagnostic procedures.

 

The group also develops metrological infrastructure to support smart grids, enabling accurate monitoring, analysis, and control of power systems in the context of digital transformation and the energy transition.

 

In addition, the group conducts research on advanced nanomaterials for applications in energy conversion and storage. This includes the development of novel materials and concepts for converting electrical energy into chemical energy carriers, as well as experimental investigations of electromechanical coupling in ferroelectric and defect-engineered metal oxides, with a particular emphasis on the role of defects and ionic dynamics in energy conversion and storage processes.

Expertise and know-how

  • Measurement, modeling, and diagnostics of power systems
  • Power system disturbance simulators and calibration of non-sinusoidal voltages and currents
  • Metrological infrastructure for smart grids
  • Cleanroom techniques (lithography, thin-film deposition, electrical transport measurements, and electron microscopy)

Research infrastructure

Laboratories

  • Laboratory A244 – Laboratory for electrical measurements
  • Laboratory A249

Equipment

  • Calibrator: CALMET 300B
  • STER synchrophasor measurement unit (PMU)
  • Power quality meter: ION7650
  • NI CompactRIO cRIO-9035 real-time controller
  • LCR meter: HP 4284A
  • Dynamic signal analyzer: HP 35665A
  • Digital multimeter: HP 3458A
  • High-voltage voltage transformer (VT): NMT 110/0.1/0.1 kV/kV/kV and high-voltage current transformer (CT): SMT 300(600)/1/1/1/1 A/A/A/A
  • Generation and measurement of voltages up to 110 kV AC and 100 kV DC, and currents up to 2000 A AC and 200 A DC
  • Measurement of very low electrical resistances (10 A and 200 A micro-ohmmeters) and very high electrical resistances (tera-ohmmeters with 5 kV and 110 kV test voltages)
  • 10/0.4 kV, 630 kVA distribution transformer with a 10 kV oil circuit breaker integrated with a Siemens overcurrent protection system
  • Inductive and acoustic partial discharge measurement system
  • Thermal imaging camera with 320 × 240 pixel resolution and a measurement range from –20 °C to +600 °C
  • Diagnostic system for testing power transformers, voltage transformers, and current transformers
  • 48 V lithium-ion and lead-acid battery packs, equipment for capacity measurements, and diagnostic instruments for determining State of Health (SOH) and State of Charge (SOC)
  • Electromagnetic field strength spectrum analyzers for extremely low-frequency (ELF) fields and mobile communication networks
  • Equipment for testing grounding (earthing) systems and determining the electrical properties of soil
  • Process measurement instrumentation, including Class 1 sound level meter, illuminance meters, temperature and relative humidity sensors, anemometers, pressure gauges, and analyzers for the electrical properties of liquids.

Key projects and references

  • Power engineering measurements, modeling and diagnostics
  • Power system disturbance simulator and non-sinusoidal voltages and currents calibrator
  • Metrology infrastructure for support of the intelligent power grid

Collaboration opportunities

  • Measurement and diagnostics of power systems
  • Power quality measurement
  • Determination of the geoelectrical and geothermal properties of soil