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The conclusion draws from traditional power supplying capability evaluation method can not reflect the actual supplying capability of gridby quantitative index, so evaluating the overall power supplying capability by means of fuzzy method has its advantage. Fuzzy analysis method has been employed to create a city gridpower supplying evaluating model in respect of the reality of power supplying condition of KunMing network, in which weighting is assigned by effect value of data reflected by information entropy to avoid the influence of subjective elements in weighting assigning. Seven elements which reflect the power supplying capability of KunMing grid objectively and comprehensively have been chose to construct corresponding membership degree function curve according to their different reflecting dimensionalities of power supplying capability, then the membership degree value of each elements is deduced. Each of the seven evaluating elements is judged to obtain quantitative fuzzy evaluating results, and then these 7 elements are combined to judge the power supplying capability synthetically to derive the fuzzy evaluating result of power supplying capability of KunMing network.

The classical four-state component model haven't accord to practical situation because the equipment repairing technique based on condition of component developed quickly, and this paper put forwarded an advanced four state component model. That model redefined abnormal state and maintainable state, combined repair state based on condition of component and schedule repair state to repair state and then confirmed the conversion relationship and the parameter to each state. This paper put forwarded combining components and dividing subzone method to simplify the main electrical scheme to be a simple directional network, applied advanced four state component model in that network to calculate the subzone's reliability parameter. Applied the least path searching method to search the least path matrix for the network and predigested the method by matrix multiplication, enumerated each fault state of that network by analytical method, worked out the reliability index of that network by VC++. And the reliability index of network is the reliability index of main electrical scheme in ChuXiong plusmn800 kV rectifier station. At last this paper analyzed the result of main electrical scheme's reliability and it proved the method's validity which used in this paper.

As one of the most important equipments to guarantee power gird operating safely and stably, the fault diagnosis of transformer has most important sense. Since the general diagnosis methods such as DGA and attributes' reduction of rough set haven't enough precision for transformer's fault diagnosis, Extenics and rough set theory are brought into diagnosing the fault of transformer. Using attribute predigesting method in rough set theory to classify the attribute term which needed by each fault diagnosis. Then building matter element model for transformer's fault diagnosis. Using DGA testing datum to be attribute set and the transformer's standard fault model to be the decision set for transformer's fault diagnosis. Utilize association function from Extenics to count each fault degree. Define the fault accepting rule to get transformer's fault. Use this method to diagnose one fault transformer and the diagnosis result matched case of fact fault. Apply this method to diagnose 76 DGA testing data and the right ratio of diagnostic result is better than IEC method.