Research On Power Grid Cascading Failures

In recent years, within worldwide several large area outage accidents caused by cascading failures made huge economic loss,brought about great influence to people's normal life, and enangerd public safety seriously, which attracted many country's universally attention all over the world, and made us think over about safety problems of power grid. The development for power grid of our country have steped in a new stage of large-scale power grid, the Large Turbine Unit, automation and information, safe and reliable power supply will make significant importance to constructing stable economy develop environment. power systems in Jiangxi province center on Nanchang, north to Jiujiang, south to Ganzhou, east to Shangrao, west to Pingxiang, interconnect with central china power grid by three 500kV lines; Presently the main network of power systems dominated by 220kV in Jiangxi province is staying in the transition period from 220kV to 500kV, while 500kV is coming into being. Parallel operation of 500kV and 220kV power networks and unit operating of 600MW in recent years result in the increasing possibility of large area outage, which brings in more danger to safe and stable operation of the system.First this paper has summarized some basic conception of power grid cascading failures and research status home and abroad, then made a deep analysis on the typical cascading failures accident of power grid at home and abroad, then we found that some significant next disruptive events resulted from initial disturbance are the key reason to a wide range of outage. From a series of simulation analysis on the effective relation of initial disturbance and subsequent event, we found that certain elements'disconnect tended to cause great reactive power variation. Base on this, this paper carry out overall serious failure analyses to power systems in Jiangxi province, by the methods of analysis on power grid cascading failures, from two aspects of large outage analyses and prevention. Through demonstration, this paper made certain that cascading failures in the west, the south, the center of the power systems in Jiangxi province influenced great to the power system, so the paper carried out emphases research on the cascading failures in the three areas, and checked the enduring ability and finally made certain security level and weak link of the Jiangxi systems under cascading failures, also supplied methods of instruction and reference frame for preventing large area outage accidents caused by cascading failures, and contributed a kind of virtual solve instrument for the practicality of cascading failures analysis method, even had practical significance for the development of cascading failures analysis and forecast in our country.