Study Of Complex Interval Power Flow And Solution To Its Conservative Property

With the emerging of power market, uncertainty in planning and operation of power system increases. Conventional certainty analysis methods expose their limits, so uncertainty analysis methods have been paid more and more attention. Power flow calculation, as one of the most fundamental tools for power system analysis, also has some difficulties in dealing with uncertainty. Therefore, interval power flow as one of the most important uncertainty analysis tool for power system is drawing more and more attention too.This thesis is focused on the study of complex interval power flow and solution to its conservative property, and the main work is as follows.1) The reason for interval operation correlation is explored. And methods of reducing ultra width arisen form interval operation are summarized.2) Three kinds of representations for complex interval including complex box, complex disk and complex fan are proposed. According to the property of meshed structure and radial operation for distribution network, an improved complex power flow algorithm based back/forward sweep method is proposed.3) Complex interval algorithm for distribution power flow calculation with different representations for complex interval is proposed. Taking a 33-bus system as the test system, conservative property of the results of interval power flow is studied.Conclusion drawn from this thesis is that conservative property in the interval power flow calculation can be reduced by choosing suitable representations for complex interval,which is based on the difference of elementary components that makes up loads in power system..