Task 3.1 Small scale harmonic power system stability (PhD)

Objectives and Research content:

To be able to define and perform stability analysis of a given power electronic (PE) based power system, which includes calculation of the overall risk of harmonic resonance problems.
Presently, no tools to assess the impact of harmonics on the power system stability exist.

With the ever-increasing use of PE acting both as load, generation and compensation, power system reliability is endangered and the needs for methods to mitigate such foreseeable problems must be met.

Methods to assess harmonic stability will be developed on a simplified system, which also is available in the laboratory. It is a micro-grid with different power electronics based sources and loads.

First, the system is appropriate modeled to be able to simulate in time-domain and validate by measurements. Next the developed models for harmonics are used to perform harmonic system analysis, identify potential problems and introduce solutions for mitigation of harmonics.

A method to indicate whether the grid is in a low risk or a high risk category in terms of harmonic instability will be developed. The methods are validated in a micro-grid to identify deviations and even improve the developed tools.