Research On Bridgeless Power Factor Correction Technology Based On DSP

Reducing Electrical network harmonic pollution which traditional rectifiers produce, andimproving the power factor of the device, have been paying close attention by scholars athome and abroad. With the continuous development of digital control technology, most of thecontrol strategy have been realized through the digital signal processors, and digital controlhas become the trend of the design of switching power supply products.In this paper, the digital control platform is built by the digital signal processor (dsp) torealize the digitization of power factor correction control. In the topology aspect, using thedual-coupling inductance bridgeless Boost PFC circuit. The dual-coupling inductancebridgeless Boost PFC circuit not only retains the advantages that the bridgeless Boost PFCconverter does have the rectifier bridge, but also achieves the boost diode natural turn-off andthe switching zero-current turn-on, enhancing the circuit efficiency furtherly. In the controlstrategy aspect, using the single-cycle control. This novel control strategy use the pulse and thenon-linear attribute of switch converters to achieve the transient control of the chopper voltageand current average. In the sampling algorithm aspect, using an improved single-cyclesampling. When the duty cycle is greater than0.5, we will select the sampling point on themidpoint of the current rising edge, otherwise on the midpoint of the falling edge, to avoid theimpact of the high frequency noise on system performance when the switch turn on or turn off.Finally, this article use the classical PI controller to control the error signal,which make theoutput voltage remain constant.Building the system model of the whole circuit with the Simulation tools——Simulink inMatlab.Modeling and simulating the dual-coupling inductance bridgeless Boost PFC circuit toverify the feasibility of the system theory. Producing a prototy with100kHz and300W(400V/0.75A) based on the dual-coupling inductance2d DBPFC converter. Using the C2000 series TMS320F2808DSP chips which made in TI corporation for digital control., Using thetheory of single-cycle control, we have not only achieved power factor correction and voltagestabilization, but also achieved the boost diode natural turn-off and the switching zero-currentturn-on, which have improved the system’s efficiency. The experimental results has furthervalidated the correctness of the theory and simulation analysis, and reached the desired effectof the experiments.