Research On Multi-contact Distribution Network With Distributed Intelligent Feeder Automation System

As the increasing requirement of power supply reliability and Short power outage, Multi-contact mode of distribution network with its advantage of high load rate has been developed. But the increase in the number of contact switch makes the operation mode more complex. Rely on the mainstream centralized feeder automation (FA) technique for multi-contact distribution network troubleshoot, power recovery time is minute level, that is difficult to meet the requirements of short-term power outage. Compared with the centralized FA, distributed intelligent feeder automation(DIFA) has the advantages of fast response speed and well control performance. Based on the above background, this paper uses DIFA technology to handle with fault of multi-contact distribution network, the main work is as follows.The paper summarized three common multi-contact distribution network connection mode including multi-segment and multi contact connection mode, many work and one backup connection mode and the SSP of the casecade connection mode, structure characteristics and mode approach. At the same time, recommending the connection model which the mode processing is not applicable.The DIFA system is studied, including the structure and the working principle of fault location, isolation and service restoration. Taking the "hand in hand" ring network fault as example, to introduce the DIFA system working principle of fault location, isolation and service restoration, and then put forward the new problem troubleshooting with multi-contact distribution network using DIFA system.The feeder dynamic topology identification method based on DIFA technology was proposed. This method is identified by its own distribution terminals, master distribution terminal by the feeder to collect static topology and switch state distributed storage, so as to establish feeder topology. At the same time, relying on the dynamic identification of contact switch to update the boundary of feeder, to notify the master terminal distribution feeders topology update. When a fault occurs in distribution networks and successfully isolated, the distribution terminal which detected the switch from close to breaking state and the switch is corresponding to the downstream side of the point of failure according to the way of main control terminal distribution using feeder topology identification method to establish the topology of the feeder topology.Proposed a multi-contact distribution network recovery algorithm rely on DIFA system, the algorithm use multiple tree to describe the topology of the recovery area and Contact switch number attribute identification and marking of each node in the tree. According to the number of attributes to determine the order of contact switch in the area to be restored searching the load can be transfer. Find the dividing point marked for the segment switch and extending its "control sub" command and extending "control close" command to the contact switch corresponding to the dividing point. The algorithm has the advantages of clear direction, production speed, can meet with the distribution network for real-time and reliability requirements.Developed an intelligent terminal, which suitable for fault location, fault isolation and supply restoration algorithm in multi-contact distribution network rely on DIFA, as the carrier of the fault recovery algorithm for the multi contact distribution network. Including hardware design, software platform, Including hardware design, software platform and software module design for fault location, isolation and service restoration by DIFA.