含右半平面零點(diǎn)的SIDOBuck-Boost變換器控制策略研究

中圖分類號：TM46 文獻(xiàn)標(biāo)志碼：A

Abstract：Aiming at the problems of serious cross influence，control dificulty and poor transient performance of the two output branches of the single inductor dual output Buck-Boost converter（SIDO Buck-Boost）with nonminimum phase characteristics，a control strategy based on the extended state observer（ESO）combined with the differentialflatness based control（DFBC）of the main circuitand the improved dual closed-loop active disturbance rejectioncontroller（ADRC）ofthebranch circuit is proposed.Firstly，basedonthetheoryofdiferentialflatness，a differentialflatnesscontroller is designedinthemaincircuit control，anderrorfeedback isprovided for the differential flatness system.ESOis designed to observe the disturbance term of the main circuit，andtheobserved statevariablesare fed back to thediferential flatnesscontroler.Secondly，to solve the problemof branch coupling andright half plane zero，an improved dualclosed-loop ADRC is designed to decouple the system.The current inner loop selects ADRC based on modelcompensation and feedforward compensation，and the voltage outer loop selects ordinary ADRC.Then，Lyapunovtheory is used to prove the stabilityof the system.Finaly，a simulation model was built on the Matlab/Simulink platform，andan experimental platform was built based on HIL.The simulation and experimental results show that the proposed control strategy reduces the cross influence between the two output branches，solves the problem of non-minimum phase system control dificulty，and improves the transient response performance of the system.

Key words： DC-DC converter;SIDO Buck-Boost converter;right half plane zero; extended state observer;differential flatness based control;active disturbance rejection controller

近年來，隨著便攜式設(shè)備的快速發(fā)展，其功能和結(jié)構(gòu)也變得更加復(fù)雜.由于這些設(shè)備內(nèi)部需要不同大小的供電電壓，因此體積、成本和效率等成為人們關(guān)注的重點(diǎn)[1-3].單電感雙輸出（single inductordoubleoutput，SIDO）Buck-Boost變換器僅使用一個(gè)電感，便可將一路輸入電壓轉(zhuǎn)換為兩路不同等級的輸出電壓，具有功率密度高、體積小、效率高以及寬輸出等優(yōu)點(diǎn)，在便攜式設(shè)備領(lǐng)域有廣闊的應(yīng)用前景[4-6].SIDOBuck-Boost由于共用一個(gè)電感，因此一條支路的輸出電壓波動會影響另一條支路的輸出電壓，即系統(tǒng)存在嚴(yán)重的交叉影響[7].同時(shí)，該變換器先導(dǎo)通支路的暫態(tài)數(shù)學(xué)模型含有右半平面零點(diǎn)（righthalfplanezero，RHPZ），使得該變換器呈現(xiàn)出非最小相位特性，從而導(dǎo)致該變換器存在暫態(tài)性能差、控制困難等問題[8].

為了減小SIDODC-DC變換器的交叉影響，國內(nèi)外文獻(xiàn)提出了許多控制策略.文獻(xiàn)[9]采用時(shí)分復(fù)用理論，避免了支路間的交叉影響，但是該變換器工作在電流斷續(xù)模式下.文獻(xiàn)[10]采用無交叉影響的V控制，抑制了交叉影響.文獻(xiàn)[11]利用滑模自抗擾控制對變換器進(jìn)行解耦，有效地抑制了交叉影響，但非線性自抗擾控制對于參數(shù)的選取要求很高.文獻(xiàn)[12通過峰值電流控制耦合 SIDOBuck ，解決了交叉影響.以上文獻(xiàn)都是基于SIDOBuck變換器，對于含有RHPZ的SIDOBuck-Boost變換器如何抑制交叉影響未見報(bào)道.

對于含右半平面零點(diǎn)的DC-DC變換器，已有較多文獻(xiàn)進(jìn)行了研究.文獻(xiàn)[13]提出了Boost變換器輸出電容電流采樣的方法，并將其應(yīng)用于滑模控制中，該控制……