Innovative Voltage Regulation Method for Distribution Networks with Distributed Generation

The presence of a significant distributed generation (DG) capacity in distribution networks would result in some conflicts with present system operation criteria, mainly because, unlike the meshed transmission system, the distribution system is usually designed as a “passive” radial system, which is conceived with neither generators operating in parallel nor power flow control. The present paper deals with voltage regulation issues in MV distribution networks connecting DG systems and proposes a new voltage control method that allows to avoid typical under/overvoltages occurring when distributed generators are operated in parallel to the network. The advantages of the innovative regulation procedure are due to a direct involvement of DG and to the possibility to be harmoniously integrated with the present Italian network control systems. The presented work is part of a research project conducted by the authors in collaboration with ENEL Distribuzione S.p.A. (which is the major Italian distribution operator).