Harmonic generation by HVDC schemes involving converters and static VAr compensators

The paper makes use of interactive harmonic analysis (IHA) to examine the harmonic behaviour of an HVDC scheme. The scheme is treated as a complete system including HVDC converters, static VAr compensators, system impedance and harmonic filters. It is shown that the type and performance of the controller can have a significant effect on harmonic behaviour. The paper illustrates, by analytical and computational analysis, the effect of equally pulse spaced (EPS) controllers and voltage zero crossing (VZC) type for both the above power electronic circuits. The EPS has clear advantages for 6 and 12 pulse HVDC converters but has little influence on the behaviour of thyristor controlled reactors. The need to represent the complete systems is highlighted by example