基于分数阶线性自抗扰控制的LLC谐振变换器

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中图分类号： TM46 文献标志码：A doi：10.12415/j.issn.1671-7872.24203

Abstract：To address the issues of poor dynamic performance and weak disturbance rejection capability in LLC resonantconverters under traditional controlmethods，a fractional linear order active disturbance rejection controller （FOLADRC） was designed and applied to theclosed-loop control system of a half-bridge LLC resonant converter. Initially，the smal-signal model of the LLC resonant converter was obtained through the extended describing function method，andthe system transfer function was obtained through reduction in Matlab.Subsequently，the linear active disturbance rejection control （LADRC） framework was modified by eliminating the phase-lag-inducing tracking diferentiator to mitigate dynamic response delays. Concurrently，the error feedback control law in LADRC was replaced with a PDμ controller，where the fractional-order differential term μ from the fractional-order PID （FOPID） controller was introduced to optimize system dynamic performance.This modification enabled the

FOLADRC to simultaneously maintain the disturbance rejection capability of conventional LADRC and achieve the enhanced dynamic performance characteristic of FOPID control. The transfer function of FOLADRC was further derived，followedbythegenerationofclosed-loopsystemBodediagrams using Matlab to validate thecontroler's stability margin through frequency-domain analysis. Subsequently，a 30o W-rated experimental prototype was constructed where comparative tests were conducted employing PID，LADRC and FOLADRC control strategies. The results show that in the positive and negative load step response conditions，compared with the PID controler， FOLADRC shortens the transient adjustment time by 47.37% and 60% respectively. Compared with the LADRC， the transient adjustment time is shortened by 20% and 31.03% respectively， significantly improving the system's dynamic response speed and anti-interference capability.This study provides an effective solution for optimizing the performance ofLLC resonant converters through the integration of fractional-order control and active disturbance rejection theory.

Keywords：LLC resonant converter; fractional order control; active disturbance rejection control（ADRC）; dynamic response; disturbance rejection capability; power conversion; power converter; robust control

LLC谐振变换器作为一种高效的隔离型DC/DC变换器，凭借其软开关特性、高转换效率以及低电磁干扰（electromagnetic interference，EMI）等优势，在新能源发电、电动汽车、工业电源、数据中心和通信设备等领域得到广泛应用[-4]。（剩余12063字）