Distribution level STATCOMs (DSTATCOMs) for load voltages support

In this paper we investigate impact of distributed compensators on power system voltages in steady state. We use the principle of the superposition to show that it is more efficient, in terms of VArs supplied to power system, to provide voltage support in load centers at distribution side of bulk power delivery substation then on its transmission side. The case one incoming transmission radial line-one bulk power delivery substation is transposed to more general one incoming transmission line delivering power to N outgoing distribution circuits where each distribution circuit has its own static VAr system providing voltage support. The line is firstly modeled as lumped inductance and later, distributed parameters are used. The higher efficiency of N distributed compensators on distribution side versus one lumped compensator on transmission side of substation is proven using Kirchhoff´s laws. The feasibility of proposed voltage support scheme is demonstrated by vector diagrams and detailed numerical simulation. The simulation is performed by Hypersim, a real time simulator and software for great accuracy developed by Hydro-Quebec research institute.