A fuzzy expert system for substation design

Computer aided design (CAD) cannot complete some policymaking procedures of substation design, such as defining the main electrical connection. One can solve these problems by applying fuzzy expert system theory to CAD. The paper proposes a method of expressing all relative factors to the main electrical connection plan in a few fuzzy subsets, compute the membership degree using the Derfei method with degree of belief, and calculate the synthetical value using a weighted fuzzy logic conjunction formula. The authors expound the process of obtaining the best plan and an AI-CAD system. An example shows that this method can shorten the design time, simplify the design program, and improve the quality of the design.