Mitarbeitende

Research Topic

Causes, propagation paths and interactions of PE/PA currents; modelling of components at the grid side of converter.

The use of power electronic systems is essential for the implementation of climate protection goals and energy saving plans. For a Variable Speed Drive (VSD) System, the most important EMI noise source is the common mode voltage, which in the case of the three phase system is the displacement of the neutral point from the earth potential.

At the grid side, the passive diode rectifiers, also known as Diode-Front-End (DFE), are predominantly used which do not feed any power back into the network. It cannot be avoid that common-mode voltages arise between the grid and the DC link. In a few cases, Active-Front-End rectifiers (AFE) are also used at the grid side. In this case, PWM-frequency common-mode voltages are also generated.

The common-mode voltages generate corresponding common-mode currents that flow in the PE or PA wires. The undesirable effects of the PE/PA currents are:

• Disturbance of communication facilities

• Heating of components in EMC filters

• Fault / false tripping of residual current circuit breakers (RCD) corrosion

Main targets of the Project PEPA:

• Systematisation and description of the causes and propagation paths of the PE / PA currents

• Creation of a modelling environment and a model library with which PE / PA currents up to a frequency of 150 kHz can be calculated and determined

• Comparison of the models through measurements on a reference system

Current open topics:

• Frequency model of three phase transformer

• Using Artificial Intelligence methods to model the nonlinearity of B6 rectifier.

• Design EMC-filters

If you are interested in these topics, please contact me for further information.