Research And Design Of Active Power Factor Correction Circuit

In the latest years, with the fast developing of electronic science and technology, the devices of switch power supply have been used in the field of manufacture and living gradually extensive. However, because of the low power factor of these devices, it has injected a lot of harmonic in electrical power system, which causes the harmonic pollution problems are increasing seriously. The active power factor correction (APFC) technology is an important method which can increase the power factor and reduce the rectification circuit harmonic current. This technology can make the input current to be sinusoidal wave with the same phase with the input voltage, and make the rectification circuit doesn’t produce harmonic current basically. The APFC technology becomes a hot research subject.Boost with the advantages of input current can be continuous, input current ripple smaller and power switch driver simple. One-cycle-control is a large signal nonlinear pulse width modification (PWM) technology, and because there is much advantage of one-cycle-control theory, such as simple circuit structure, high control precision and fast dynamic response. It is very suitable for active power factor correction circuit.This thesis identified the One-cycle-control Boost APFC circuit as the research target. Firstly, this thesis analyzes the structure and work principle of Boost converter, set up state space averaging model and small signal model, derives the relevant transfer function. The third chapter studies the one-cycle-control technique, analyses the resistance to disturbance performance discusses work principle of the one-cycle-control Boost APFC circuit in detail, designs voltage and current control ring respectively, gives each control loop transfer function, introduces a method to determine the control parameters. The fourth chapter designs a500W simple of one-cycle-control Boost APFC, expounds main circuit and control circuit design method in detail, according to the design index selection the corresponding devices, calculates the efficiency of the circuit. The fifth chapter main designs the auxiliary power and protection circuit. The sixth chapter simulates main circuit and control circuit of APFC by the simulation software--MATLAB and designs an experiment prototype with IR1150, gives simulation and experimental results.The simulation results indicate that the circuit achieves the designing specification and the expecting electrical characteristics, also verifies the correctness of the theoretical analysis and circuit design in this thesis. Experiment result shows that one-cycle-control Boost APFC can achieve input current follow the input voltage variation, and the shape of current waveform as sine, power factor closes to1.