  The paper deals with the optimal sizing and allocation of dispersed
generation, and distributed storage systems. The optimization aims at
minimizing the sum of the costs sustained by the distributor for the power
losses, for network upgrading, for carrying out the reactive power service and
the costs of storage and capacitor installation, over a planning period of
several years. Also, analysis of the effect of distributed generation capacity
and location on voltage stability enhancement of distribution networks are
presented in this paper. The analysis is performed using a steady state voltage
stability index which can be evaluated at each node of the distribution system.
Different optimal capacities and locations are used to check this effect. The
location of distributed generation has the main effect on the system voltage
stability. Voltage stability should be taken into account as one of the
objectives of distributed generation optimal allocation techniques. The
analysis is conducted on a 69-node distribution system in order to show the
feasibility of the proposed procedure.
