Study On VPP Modeling And The Interaction Mode Between VPP And Distribution Network

Distributed Generations will become the important energy source of future power grid, on the meantime, a large number of active load nodes pouring into the power distribution network makes the operation of it more complicated and flexible. With the development of both power side and demand side, the distribution network becomes a more interactive one. Virtual Power Plant, an effective way in connecting the Distributed Generations and the distribution network, plays dual roles in guaranteeing safe operations of the grid and providing a platform for DGs to participate in the power market. VPP realizes the integration and allocation of resources, serving as a feasible implementation way of intelligence in the power side of smart grid. This paper considers the integration method of VPP, provides the structure model, control model and scheduling model based on the basic concept of VPP technology. In the paper, the concept and structure of VPP are described systematically and the combining approach between the VPP pseudo-entity and the hardware of the power system, the realization of two-way choice and the operating mechanism of VPP are also stated in the general. Take the hierarchical control concept of Micro-grid as a reference, this paper proposed the VPP hierarchical control strategy based on multi-agent system. In this strategy, the distribution network control is at the highest level, VPP control of its resource modules is the third-level control, the secondary level is the module control of its containing resources, and the first level control is the independent control of distributed resources itself. The strategy method is applied to frequency regulation of the system and a power allocation model of VPP frequency regulation is established. The effectiveness of the model in forming a frequency modulation characteristic curve representing the VPP is verified by a case study. The VPP can be dispatched by the distribution network based on the curve and the unbalance power arranged can be allocated in its internal modules reasonably. This article also studies the interactive mechanism between distribution network and VPP, puts forward the scheduling model of virtual power plant according to the idea of integration emphasizing on the process of the forming of VPP cost curve and its dynamic output range mainly used for day-ahead scheduling.