Design And Implementation Of Single Phase Full Controlled Rectifier

Usually, the traditional AC-DC circuit generally uses the bridge rectifier circuitand a large filter capacitor DC voltage. However, the load is generally not pureresistance, the direct use of bridge rectifier output power to the load will make thecurrent distortion, reduce the power factor&efficiency, produce a large number ofharmonics, resulting in serious harmonic pollution to power grid. Therefore, theresearch on power factor correction is very necessary. In the active power factorcorrection converter, current changes with voltage with the same frequency and phase,so it can realize high power factor, but also can regulate a higher output DC voltage toobtain power for the post stage circuit.The thesis presents the design and implementation of single phase full controlledrectifier, using digital control of the bridgeless APFC. The topological structure andworking principle of the main circuit are described. Not only the control strategiessuch as multiplier, voltage follower and single cycle control but also the controlmethods of several kinds of peak current, average current and hysteresis current areanalyzed. The performances are compared between bridgeless APFC and Boost PFCin order to realize the optimization of the main circuit. The hardware designintroduces not only the selection of the key components such as main controlprocessor using DSP chip Delfino of F2833X series, power switch using InfineonF4-50R12MS4, filter capacitor parameter and boost inductance calculation but alsothe schematic diagram design of main control circuit, ADC circuit, sampling circuit,filter circuit, power supply circuit, display circuit. The software design introducesscheme as well as flow charts of programs including the main, the interrupt, ADC,double closed ring control, soft start.The circuit simulation is made up in the MATLAB SIMULINK, to verify thefeasibility of the design, and a prototype is built for experimental testing. Simulationand test results show that no bridge APFC rectifier can obtain the same propertieswith special chips rather using Delfino F2833X control. The system achievesexcellent performances as stable380V DC output voltage, strong load capacity,0.98power factor,3.8%THD and95%efficiency.