A study on autonomous decentralized voltage controller in distribution network considering control priority

It is of prime importance to introduce a large amount of distributed generators in order to solve the energy and environmental issue. In distribution network with a large amount of distributed generators, it becomes difficult to maintain the system voltage within an allowable range. Thus, we have developed a new voltage control method using reactive power control of system connection inverter. Especially, the method is based on the autonomous decentralized approach because it will be difficult to treat a large number of distributed generators by a centralized manner. And the method is composed by three control modes and they are switched by voltage change. However, such a switching control method often becomes unstable especially in the case the dead time is included in the control block. Hence, in this paper, we have developed a new method which is based on not the switching control but the continuous control. The autonomous decentralized controller for voltage profile maintenance is proposed and its dynamics are discussed in this paper.