The Research Of The Chaos Modulation Method Reducing The Cuk Converter's EMI

With the rapid development of power electronic technology, and the wide spread use of power electronic equipment in all works of life, the electromagnetic interference of various power electronic equipment has been more and more prominent. Traditional technologies of restraining electromagnetic inference mostly managed to cut it off after it has radiated. However, those ways are passive because the electromagnetic inference has already been caused and they can not meet the demands to restrain electromagnetic inference recently. With the deep research and development of Chaos theory in the power electronic field, we get the possibility of restraining interference initiatively from the source through utilizing Chaos theory. Because of the continuous deeper research of scholars in the world, there have been several chaos control methods to reduce the electromagnetic inference of converters, including parametric perturbation and chaotic modulation. The paper mainly studies that when Chua's dual circuit is regarded as the chaotic source of chaotic modulation, whose results of restraining the electromagnetic inference of converters. And this way will be analyzed by compared with another two ways. The specific details fall into three parts:Firstly, the Cuk converter is the studying subject of this paper. On the basis of traditional modeling, the Cuk converter is optimized. Then we test the modeling by simulink simulation. On the basis of optimized mathematical model, the bifurcation diagram of Cuk converter and the spectrogram of Cuk converter in standard PWM pattern are given. After that we can see that the optimized modeling method is superior and better than the traditional modeling, for example, the iterations of discrete time with mapped-method will be reduced, the information of convert nonlinear which traditional modeling doesn't have will be showed, and the Lorenz chaotic modulation method's electromagnetic interference to convert will be achieved.Secondly, Chua's dual circuit, which is superior and better than traditional chaotic sources, is chosen to be the chaotic sources of chaotic modulation method and the output signal in double scroll chaotic states is regarded as original chaotic signal needed by chaotic modulation method. On that basis, combining with random signal, give a simulation method of chaotic modulation method and encapsulate the three modules of chaotic modulation method into subsystem, from which can get the simulink simulation general drawing with Chua's dual chaotic modulation method. Next, by simulation comparison of current harmonics of Cuk converter respectively in chaotic modulation method and standard PWM pattern, can see the results of Chua's dual chaotic modulation method resisting the electromagnetic interference of Cuk converter.Thirdly, make comparative analysis on the effects of reducing electromagnetic interference respectively in those three different ways, parameter perturbation method, Lorenz chaotic modulation method and chua's dual chaotic modulation method. The conclusion is that chua's chaotic dual modulation method's effects on reducing electromagnetic interference is best.