To solve the problem that the generators can improve their market power in PAB auction repeatedly by auction learning, based on the PAB auction mechanism in the electricity market, the random matching mechanism of optimal probability was proposed, an optimal probability distribution method was developed to minimize the average transaction price，and the information disturbance of probability was used to affect the learning ability of generators and weaken theirs market power behavior. Simulations showed that compared with the price level matching mechanism and completely random matching mechanism, random matching mechanism of optimal probability can affect the learning ability of generators more effectively.
