Real-time decentralized voltage control in distribution networks

Voltage control plays an important role in the operation of electricity distribution networks, especially when there is a large penetration of renewable energy resources. In this paper, we focus on voltage control through reactive power compensation and study how different information structures affect the control performance. In particular, we first show that only using voltage measurements to determine reactive power compensation is insufficient to maintain voltage in the acceptable range. Then we proposes two fully decentralized algorithms by slightly adding additional information into the control design. The two algorithms are guaranteed to stabilize the voltage in the acceptable range regardless of the system operating condition. The one with higher complexity can further minimize a cost of reactive power compensation in a particular form. Both of the two algorithms use only local measurements and local variables and require no communication.