Voltage Stability Research Based On Multi-agent For Distribution Network With DGs

In recent years, distributed generation technology has been vigorously advocated and developed because it is flexible, efficient, and clean. The combination of power grid and distributed generation is considered to be the main trend of the power industry in the future. But the voltage of the distribution network may overstep the limit because the DG Itself is unstable, which will reduce the stability of the distribution network. Therefore, a voltage control method based on the Multi-Agent technology is proposed to optimize the voltage of the distribution network.This paper firstly focuses on analyzing and researching the effects of the voltage profile and the voltage stability of the distribution network considering injected location,interconnected capacity and the power factor of the distributed generations. Using Lij which can measure the static voltage stability of distribution network to determine the most weak Voltage node of the distribution network. The simulation results show that only the reasonable injected location, interconnected capacity and the power factor can exert the effect of the distributed generations which can support the node voltage of the distribution network. Otherwise, the voltage may overstep the limit.Then this paper introduces the technology of Agent and Multi-Agent system. The advantages of the application of combining the DG with the distribution network are summarized based on the feature of the control structure, the way of communication, the development platform of the Multi-Agent system, which provides realistic theory for optimizing the voltage of the distribution network which contains DG.Finally, combining the Lij to determine the most weak Voltage node of the distribution network, a voltage control method based on the Multi-Agent technology is proposed to reduce the impact on the distribution network when distributed generations are connected to it, which finally improves its static voltage stability. A control structure based on the Multi-Agent coordination control algorithm which contains the DG control Agent, the distribution network Agent and the DSTATCOM Agent is constructed, then, the coordinated control strategy of DSTATCOM and DG is established based on the slop adjustment to make up the most weak node which can improve the static voltage stability in return. Simulative results show the correctness and effectiveness of the proposed method in this paper.