Research On Switch-mode Power Factor Correction Using Intelligent Control

Switch-mode power converters in electrical energy converting area have an important role. The converters with high converting efficiency, low cost and good power control performance, have widely applied in various fields, especially in high-power converting area. In recent years, many new topology structures have been proposed such as dual-boost, and dual-buck-boost with full bridge, and there are some new switch-mode conversion technologies (ZCS, ZVS and Quasi-resonant converters). As for control methods, SFM and PSM have also applied instead of PWM. Also, non-linear control method has proposed in the converts, with respect to linear control method. Switch-mode power converts mainly consist of power switches, capacitance and inductance, through PWM control, to achieve power conversion. Especially in the AC/DC conversion, power conversion circuit needed to ensure that it must have high power factor, low current harmonic distortion and high conversion efficiency.Switch-mode power factor correction circuit usually has BOOST power circuit, PWM drive circuit and control algorithm, which key technology of the power factor correction. This paper expounds the principle of the switch mode power conversion circuit and the power factor correction, analyzes the advantages and disadvantages of the existing power conversion circuits. According to the existing switch-mode power factor correction topological structure, a new structure is proposed. Also, a new power conversion control algorithm is adopted. With the development of digital signal processing theory and artificial intelligence technology, some novel control strategies have proposed for the power factor correction algorithm. Some academics have already used fuzzy control technology into PFC. The present power factor correction algorithm is based on PID with voltage and current closed-loop, which does not make full use of switch-mode power conversion characteristics and law of the power convert circuit. In result, the performance of the traditional system control is not good, very prone to have output overshoot, and it can cause damage to the load, etc. According to the shortages, this paper makes full use of the power convert circuit with its own characteristics and proposes the intelligence control algorithm, combining the fuzzy control, expert control system and other smart control technology. By the intelligence control algorithm, traditional PID control algorithm is optimized to improve the system performance.In this paper, according to the current state of power conversion circuit, the fuzzy control algorithm to adjust PID parameters in real-time to improve the performance of the current system:In addition, with the power circuit conversion rule, expert control rules are designed, to adjust the control algorithm. The simulation results show that, for this paper advanced power conversion topology structure and control algorithm, the system has the high power factor, low harmonic distortion and good dynamic performance.