Research On Continuous Power Flower Model Considering To Static Load Characteristics And Wind Power Characteristics

The blackout led by voltage instability frequently occurs over the world in recent years,which has caused great loss. For the development tendency of huge capacity units, ultra-highvoltage network and large power system, higher security and stability of power system arerequired. Continuous Power Flower Method (CPF) is a kind of widely used research methodto static voltage stability.Load characteristics holds great weight in terms of the voltage stability, and has closerelationship to the accurate and credible of voltage stability analysis. Because ofindeterminate composition and influence from external factors, such as time, weatherconditions and economic conditions, load model research is quite complex.This paper took load static characteristics into account on the basis of classic constantpower load model and considered ZIP load model. Two kinds of load model and Jacobianmatrix are analysis, and then traced more accurate P-V curve using CPF method. The resultsof the simulation show that the maximum load power has increased after considering loadstatic characteristics. The change of characteristic value of Jacobian matrix affected staticvoltage stability. This paper also compared with power flow results under different loadcomposition. The conclusion is, the lower the constant power load rate and the more theconstant impedance load, the more the power of the maximum load node. The more theresistance load rate, the more the voltage is.Developing wind power is a very important part of future-oriented energy strategic allover the world. Due to wind turbine generation often far away from main network and loadcenter, the access point where wind power integration into power system is weak. Andrandomness and intermittency of wind speed cause unstable wind power, which seriouslyimpact security and stability of power system, especially voltage stability problem. Hence,the researches on power system voltage stability problem with wind power penetration haveimportant meaning.This paper proposed a Continuous Power Flow (CPF) approach for power systemvoltage stability analysis considering randomness and intermittency of wind powergeneration. This paper derived the average mechanical power of the wind turbine. Via sittingwind speed value matrix and minimum wind speed for wind turbine start-up, this papersimulated the wind turbine operation state under load growth. Both static load characteristicsand wind power characteristics are also considered at last. The results of the simulation showthat wind turbine mainly affect access point and the points which electrical distance are close. Appropriate selection of access point is of important to power system voltage stability.