For the rectification problem of the input stage in small energy router, single-phase full-bridge PWM rectifier circuit is used in input stage and the idea of fuzzy control is introduced into voltage outer loop control strategy. Combing fuzzy control with traditional PI control, a fuzzy adaptive control strategy of voltage outer loop is proposed. Then compared with the traditional control strategy, the control strategy proposed in this paper has good dynamic characteristics and achieves rectification or inversion of the rectifier under the condition of unit power factor, which meets the requirements of energy bidirectional transmission of small energy routers.