Voltage Regulation through Wide Area Voltage Control of HV/MV Transformers and Inverters’ Reactive Power Support

Abstract

This paper presents a technical evaluation of two different methods to avoid the excessive voltage deviations caused by dispersed generation in distribution grids. Two voltage regulation methods, wide area voltage control of HV/MV transformer and inverters’ reactive power support, are simulated in several real rural grids with different topologies located in Northern Germany. In all these analysed grids the high penetration of dispersed generation produces big power flow reversals during low load periods. The objective of implementing both voltage regulation methods is to reduce voltage deviations in such an extent that voltage band violations no longer act as the principal obstacle to host more dispersed generation in the distribution grid. We evaluate the effectiveness of these two methods through a power system analysis program and analyse the reciprocal effects caused by simultaneous use of both methods. Moreover, the concept of “voltage inhomogeneity” is introduced.