Technology Research Of 110V/200W Converter In The Continuous Peak Current Mode Control

Due to using the nonlinear components, such as power tube and energy storage elements, switching power converter behaves as a strong nonlinear system. As a result, it will not only bring a large number of harmonics into power system, but also cause the system many unstable phenomena, such as the sub-harmonic oscillation, fast scale bifurcation and chaos. These unstable phenomena worsen the working performance of the switching power converter system. Therefore, the stability control of the system needs to be further studied. This paper takes the peak current mode controlled power factor correction(PFC) Boost converter as research subject and focuses on the fast scale bifurcation instabilities. The purpose is to seek the effective control strategy and provide solutions for stable operation of the Boost converter. The main work and achieved results are as follows:a. The control effects and problems of the fixed slope compensation are studied under the peak current mode controlled PFC Boost converter. Through the simulation and experiments, the results show that the fixed slope compensation can effectively suppress the fast scale instabilities. However, it exists the compensation problems and causes a distortion of the inductor current, especially near zero crossing. As a result, the fixed slope compensation can reduce the power factor of the PFC Boost converter system.b. In order to solve the problems of the fixed slope compensation, a global optimization slope compensation strategy has been proposed according to the theory of resonance parametric perturbation. But the input voltage and power are too low to apply to the engineering in the past research experiment. In the conditions of input voltage 110 V and power 200 W, this paper continues to study unstable control under the global optimization compensation. Through the simulation and experiments, the results prove the correctness and effectiveness of the compensation strategy. At the same time, the results show that the global optimization slope compensation can not only effectively suppress the fast scale instabilities, but also solve the problems of the fixed slope compensation. Therefore, it improves the power factor of the system.