Three phase integrated load and harmonic flows.
Thesis DisciplineElectrical Engineering
Degree GrantorUniversity of Canterbury
Degree NameDoctor of Philosophy
This thesis investigates two algorithms for the steady state analysis of HVDC convertor plant. The first is an already well established frequency domain technique, known as IHA (Iterative Harmonic Analysis), and the investigation centres on the nature of the algorithm under divergent conditions. In particular, a mathematical analysis of the algorithm is used to prove that divergence of the algorithm is not necessarily indicative of a physical harmonic instability. The second algorithm is developed to exploit the IHA technique within the context of the three phase a.c.-d.c. loadflow as an alternative convertor model which incorporates (rather than ignores) the effects of harmonics. The resulting three phase integrated load and harmonic flow algorithm is a significant improvement on the existing single phase load & harmonic flow algorithms. Finally, the integrated algorithm is applied to two test systems drawn from the New Zealand primary network, and is shown to be a significant improvement over the IRA algorithm alone, resolving the inconsistencies which exist between the fundamental frequency and harmonic models of the convertor.