當(dāng)今電子系統(tǒng)如高端處理器及記憶體,對電源的需求是趨向更低電壓、更高電流的應(yīng)用。同時(shí)、對負(fù)載的反應(yīng)速度也要提高。因此功率系統(tǒng)工程師要面對的挑戰(zhàn),是要設(shè)計(jì)出符合系統(tǒng)要求的細(xì)小、價(jià)廉但高效率的電源系統(tǒng)。而這些要求都不是傳統(tǒng)功率架構(gòu)能夠完全滿足的。Vicor提出的分比功率架構(gòu)(Factorized Power Architecture FPA)以及一系列的整合功率元件,可提供革命性的功率轉(zhuǎn)換方案,應(yīng)付以上提及的各項(xiàng)挑戰(zhàn)。這些功率元件稱為V•I晶片。
為深入了解基于UC3854A控制的PFC變換器中的動(dòng)力學(xué)特性,研究系統(tǒng)參數(shù)變化對變換器中分岔現(xiàn)象的影響,在建立Boost PFC變換器雙閉環(huán)數(shù)學(xué)模型的基礎(chǔ)上,用Matlab軟件對變換器中慢時(shí)標(biāo)分岔及混沌等不穩(wěn)定現(xiàn)象進(jìn)行了仿真。在對PFC變換器中慢時(shí)標(biāo)分岔現(xiàn)象仿真的基礎(chǔ)上,分析了系統(tǒng)參數(shù)變化對分岔點(diǎn)的影響,并進(jìn)行了仿真驗(yàn)證。仿真結(jié)果清晰地顯示了輸入整流電壓的幅值變化對系統(tǒng)分岔點(diǎn)的影響。
Abstract:
In order to better understand the dynamics characteristic of power factor correction converter based on UC3854A, and make the way that parameters change influences the bifurcation phenomena of the system clearly. The math model of the two closed loop circuits to the Boost PFC (Power Factor Correction) converter controller was built. Then, with the help of Matlab, the simulation for nonlinear phenomena such as chaos and slow-scale bifurcation in the PFC converter was made. Finally the factors that have influence to the phenomenon of bifurcation under slow-scale in PFC converter were analyzed. The simulation results clearly show the parameters change influences the bifurcation point of the system.