Optimization Of Multi-period Load Curtailment In Distribution Network Considering Interruptible Load

Smart Grid is the direction of the future research and development of power grids. In order to build Smart Grid, distribution network must be paid full attention. Distribution automation is one of the key technologies to realize smart power distribution system. Service restoration of distribution system is one of the key components in distribution automation. There has been a lot of research in distribution network fault recovery, however, service restoration of distribution system with Interruptible Load (IL) is less studied. Interruptible load, as an efficient solution of power supply shortage. Considering IL, in the distribution system planning together with the supply side resources can efficiently solve the problem of power supply shortage, What’s more, IL can also be applied in peak load periods, playing a role in load shifting,. Also, IL can be used as an ancillary service in spare power and transmission network. The main factors affecting the interruptible load compensation costs contain the advance time of interruption, the interruption duration, the amount of curtailed load, the frequency of interrupts, the occurrence time and the minimum time interval.This paper applied interruptible load management to the service restoration of distribution system, and established an optimization model of multi-period load curtailment in distribution network considering interruptible load. The objective is to minimize total load compensation costs and switching operation subject to basic constraints for network and scheduling constraints for interruptible load. With regard to the first objective, the factors that can affect power loss contain the amount of curtailed load and the users’willingness of interruption. The basic constraints include the radial configuration constraints, branch power flow constraints and the node voltage constraints. The scheduling constraints for interruptible load include the advance time of interruption, the interruption time, durations of interruptible loads, the frequency of interrupts, and the minimum time interval. On this basis, this paper applies the GA service restoration algorithm to a 33 bus distribution system test case in order to demonstrate and verify the feasibility and accuracy of the proposed method. By analyzing the test case results, it is possible to reveal how IL contributes to the restoration scheme. What’s more, it proved that considering the initiative of users interruption can help to reduce the power loss, and then improve the reliability of the system.