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The load model of power system is playing a more and more important role inthe analysis and computing of power system. Since the number of load type increasesrapidly, advanced research on some special loads is required to better describe thecharacteristics of various loads. Under this background, this thesis probes deep intoair conditioner characteristics and its modeling.First, this thesis gives an overview of current methods of traditional loadmodeling, and then presents the questions remained to be solved, particularly thequestion of a specific kind of electrical load --air conditioner, which increasinglyimpacts the power system stability in hot summer. According to the load’scharacteristics, the thesis describes several kinds of static/dynamic model structure,puts forward the general step of load modeling and principles of model selection. Thethesis also derives three-order induction motor models at different (d, q) planes indetail, and compares them in load modeling.In the aspect of parameter identification, this thesis explains the fundamentaltheory of nonlinear Least Square Method and its improved algorithm, ConstraintWeighted Least Square Parameter Estimation (CWLSPE). Its computer realizationflow is also introduced.Then, in order to research characteristics of air conditioner load, an experimenton air conditioner and motor are carried out in the dynamic simulation laboratory.Based on the experimental result, the thesis analyses the air conditioner loadcharacteristics in detail, including voltage static, frequency, stalling and dynamiccharacteristics. Further, the thesis makes a summary on all those characteristics, andcompares them with induction motor.Finally, a sort of special load model, air conditioner load, is constructed with themodeling methods and the experimental data, and is applied into the power systemsimulation software-PSASP. It is followed by a summarization of different effects ofair conditioner and other kinds of load to power system simulation.Directed by the theory above, the author develops a software kit for loadmodeling of power system. The software provides preprocess of sampled data. Itincludes two types of static load model, two types of dynamic load model, whichmeet the need for load model identification in power system. Moreover, the softwareprovides two methods to evaluate the rationality of the load model.
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