王志彬 朱景偉 趙錫陽(yáng) 劉詠涵 曹海川
永磁容錯(cuò)輪緣推進(jìn)電機(jī)預(yù)測(cè)占空比電流滯環(huán)控制
王志彬 朱景偉 趙錫陽(yáng) 劉詠涵 曹海川
(大連海事大學(xué)船舶電氣工程學(xué)院 大連 116026)
針對(duì)永磁容錯(cuò)輪緣推進(jìn)電機(jī)傳統(tǒng)電流滯環(huán)控制策略轉(zhuǎn)矩脈動(dòng)大的問(wèn)題,提出一種預(yù)測(cè)占空比電流滯環(huán)控制策略。在固定采樣頻率下,通過(guò)當(dāng)前時(shí)刻轉(zhuǎn)子位置、角速度及母線電壓預(yù)測(cè)電流滯環(huán)寬度,進(jìn)而根據(jù)電流相對(duì)滯環(huán)位置預(yù)測(cè)占空比來(lái)實(shí)現(xiàn)閉環(huán)控制,同時(shí)結(jié)合故障容錯(cuò)控制策略可實(shí)現(xiàn)電機(jī)一相開(kāi)路和短路故障容錯(cuò)控制。利用Matlab/Simulink搭建仿真模型,設(shè)計(jì)并調(diào)試以StarSim為核心的硬件實(shí)驗(yàn)平臺(tái),仿真和實(shí)驗(yàn)結(jié)果證明所提出的預(yù)測(cè)占空比電流滯環(huán)控制策略可有效提高電流控制精度,降低電機(jī)轉(zhuǎn)矩脈動(dòng),同時(shí)保留了傳統(tǒng)電流滯環(huán)控制算法簡(jiǎn)單和響應(yīng)速度快的特點(diǎn)。
永磁容錯(cuò)輪緣推進(jìn)電機(jī) H橋逆變電路 預(yù)測(cè)占空比 StarSim
隨著海上貿(mào)易的高速發(fā)展,船舶所需噸位和功率日益提高,傳統(tǒng)推進(jìn)系統(tǒng)在空間、能耗、噪聲等方面劣勢(shì)日趨明顯[1]。輪緣推進(jìn)器(Rim Drive Motor, RDM)將螺旋槳、推進(jìn)電機(jī)、軸承集成一體,具有結(jié)構(gòu)緊湊、效率高、綠色環(huán)保等突出優(yōu)點(diǎn),是現(xiàn)代電力推進(jìn)技術(shù)的革命性創(chuàng)新[2]。RDM內(nèi)置集成電機(jī)主要為永磁同步電機(jī)(Permanent Magnet Synchronous Motor, PMSM)[3]。永磁容錯(cuò)電機(jī)(Fault-Tolerant Permanent Magnet Motor, FTPMM)是繞組獨(dú)立的PMSM,不僅效率高、體積小,還具有良好的容錯(cuò)性和可靠性[4]。永磁容錯(cuò)輪緣推進(jìn)電機(jī)(Fault-Tolerant Permanent Magnet Rim Drive Motor, FTPM-RDM)采用FTPMM作為RDM的內(nèi)置電機(jī),既可以提高船舶空間利用率和效率,又可明顯提升推進(jìn)系統(tǒng)的穩(wěn)定性和可靠性[5]。
近年來(lái),國(guó)內(nèi)外許多學(xué)者對(duì)d=0的矢量控制算法進(jìn)行了深入的研究,研究熱點(diǎn)主要有內(nèi)外環(huán)雙PI控制、模型預(yù)測(cè)電流控制、電流滯環(huán)跟蹤脈寬調(diào)制等。傳統(tǒng)PI控制策略因其算法簡(jiǎn)單被廣泛用作電機(jī)電流和轉(zhuǎn)速控制器,但PI控制器存在參數(shù)設(shè)計(jì)及整定困難等局限性,限制了它的進(jìn)一步發(fā)展[6]。模型預(yù)測(cè)電流控制,具備原理直觀、設(shè)計(jì)靈活、多目標(biāo)協(xié)同等優(yōu)點(diǎn),但是對(duì)于多相FTPM-RDM的眾多電壓矢量,會(huì)存在計(jì)算量大、權(quán)重系數(shù)選取復(fù)雜、滾動(dòng)優(yōu)化循環(huán)次數(shù)多的缺點(diǎn)[7]。與此同時(shí),上述兩種控制策略在FTPM-RDM發(fā)生繞組短路時(shí)很難提供合理的解決方案。
電流滯環(huán)跟蹤脈寬調(diào)制(Current Hysteresis Band Pulse Width Modulation, CHBPWM)策略具備控制算法簡(jiǎn)單、易實(shí)現(xiàn)、動(dòng)態(tài)性能好、魯棒性強(qiáng)的優(yōu)良特性,目前已經(jīng)成功地應(yīng)用在眾多電力變換系統(tǒng)中[8]。相比于內(nèi)外環(huán)雙PI控制、模型預(yù)測(cè)電流控制,F(xiàn)TPM-RDM采用CHBPWM控制策略,無(wú)需各相矢量聯(lián)合,可直接對(duì)各相繞組進(jìn)行單獨(dú)控制,具備算法簡(jiǎn)單、響應(yīng)迅速的優(yōu)勢(shì)[9]。傳統(tǒng)三相PMSM由于繞組相互影響,無(wú)法精準(zhǔn)確定單個(gè)采樣周期每相繞組相電壓矢量大小,因此只能實(shí)現(xiàn)傳統(tǒng)CHBPWM策略,存在開(kāi)關(guān)頻率不固定問(wèn)題,同時(shí)不具備故障容錯(cuò)性能[10]。相比傳統(tǒng)PMSM,F(xiàn)TPM-RDM的繞組結(jié)構(gòu)和H橋逆變器可完美結(jié)合CHBPWM算法,實(shí)現(xiàn)精準(zhǔn)確定每相繞組施加的電壓矢量,進(jìn)而對(duì)單個(gè)采樣周期CHBPWM控制進(jìn)行具體分析并提出優(yōu)化算法[11]。同時(shí)當(dāng)FTPM-RDM出現(xiàn)開(kāi)路、短路故障時(shí),可通過(guò)直接控制正常相電流對(duì)故障相進(jìn)行補(bǔ)償,快速實(shí)現(xiàn)電機(jī)開(kāi)路短路容錯(cuò)控制[12]。因此采用CHBPWM策略控制FTPM-RDM,可以獲得兼?zhèn)漤憫?yīng)快速性、易實(shí)現(xiàn)、可靠性的電力推進(jìn)方案。
傳統(tǒng)CHBPWM采用單個(gè)采樣周期單開(kāi)關(guān)動(dòng)作的控制方式,受數(shù)字控制器運(yùn)算速度和功率器件允許開(kāi)關(guān)頻率的限制,實(shí)際實(shí)現(xiàn)的傳統(tǒng)CHBPWM控制的采樣頻率較低,且開(kāi)關(guān)頻率不大于采樣頻率的一半[13]。因單個(gè)采樣周期時(shí)間久且開(kāi)關(guān)動(dòng)作不變,故FTPM-RDM應(yīng)用傳統(tǒng)CHBPWM存在相電流脈動(dòng)大、畸變率高從而造成轉(zhuǎn)矩脈動(dòng)大的缺點(diǎn)。
本文通過(guò)綜合分析FTPM-RDM應(yīng)用CHBPWM控制的優(yōu)勢(shì)和應(yīng)用傳統(tǒng)CHBPWM的缺陷,并參考文獻(xiàn)[14]應(yīng)用于傳統(tǒng)三相PMSM的變占空比CHBPWM控制策略,提出一種適用于FTPM-RDM的預(yù)測(cè)占空比CHBPWM控制策略。該算法在保留傳統(tǒng)CHBPWM算法簡(jiǎn)單、響應(yīng)快速的同時(shí)有效降低了電流脈動(dòng)、電流畸變率和轉(zhuǎn)矩脈動(dòng),并且實(shí)現(xiàn)了電機(jī)一相開(kāi)路、短路容錯(cuò)控制。最后通過(guò)仿真和實(shí)驗(yàn)驗(yàn)證了預(yù)測(cè)占空比CHBPWM控制策略的可行性。
六相FTPM-RDM結(jié)構(gòu)示意圖如圖1所示,定子采用單層集中繞組,相鄰繞組的相位差為60°,每相繞組間采用電樞隔離齒,各相繞組相互獨(dú)立,有效地實(shí)現(xiàn)了物理、電氣、熱和磁隔離[15]。FTPM-RDM每相由如圖2所示的H橋逆變電路供電。
圖1 六相永磁容錯(cuò)輪緣推進(jìn)電機(jī)結(jié)構(gòu)示意圖
為了保證控制效果,在對(duì)FTPM-RDM進(jìn)行建模時(shí),做出如下假設(shè):①忽略漏磁通、磁滯損耗的影響;②各相繞組參數(shù)恒定且完全對(duì)稱;③各相繞組的電動(dòng)勢(shì)波形為正弦波。
圖2 單相H橋逆變電路
基于以上假設(shè),可推導(dǎo)出六相FTPM-RDM在自然坐標(biāo)系下的數(shù)學(xué)模型。
電壓方程為
磁鏈方程為
電磁轉(zhuǎn)矩方程為
運(yùn)動(dòng)方程為
式中,ψ為各相繞組磁鏈;i為各相電流;U為各相電壓;R為各相電阻;L各相電感;e為各相反電動(dòng)勢(shì);f為永磁體磁鏈;f()為各相磁動(dòng)勢(shì);為空間電角度;e為電磁轉(zhuǎn)矩;L為負(fù)載轉(zhuǎn)矩;為機(jī)械角速度;為電機(jī)轉(zhuǎn)動(dòng)慣量。
本文基于FTPM-RDM的結(jié)構(gòu)和H橋逆變電路的特點(diǎn),提出在固定采樣頻率下的預(yù)測(cè)占空比CHBPWM控制策略,系統(tǒng)結(jié)構(gòu)框圖如圖3所示。
圖3 FTPM-RDM控制系統(tǒng)結(jié)構(gòu)框圖
首先,轉(zhuǎn)速誤差經(jīng)PI和坐標(biāo)變換、電流檢測(cè)及故障判斷得到分配的六相給定電流,將給定電流和預(yù)測(cè)滯環(huán)寬度傳送到占空比預(yù)測(cè)單元,實(shí)現(xiàn)對(duì)FTPM-RDM的精確控制。因FTPM-RDM各相繞組獨(dú)立,各相間電壓、電流互不影響,故以A相為例,敘述本文所提預(yù)測(cè)占空比CHBPWM控制算法。
圖4 CHBPWM單周期A相電流脈動(dòng)等效圖
基于圖2的單相H橋逆變電路,在~(+)時(shí)刻,VT1、VT4管開(kāi)通,VT2、VT3管關(guān)斷,A相電流處于上升階段,在+~+時(shí)刻,VT2、VT3管導(dǎo)通,VT1、VT4關(guān)斷時(shí),繞組電流處于下降階段,忽略繞組電阻產(chǎn)生的壓降,由FTPM-RDM電壓方程式(1)可得
結(jié)合式(5)、式(6)可得
式中,為采樣頻率;dc為母線電壓;a為A相繞組反電動(dòng)勢(shì),a可由FTPM-RDM機(jī)械角速度和轉(zhuǎn)子位置求出。
確定滯環(huán)寬度后,根據(jù)當(dāng)前采樣時(shí)刻a對(duì)應(yīng)的滯環(huán)位置,可預(yù)測(cè)出下一個(gè)周期A相占空比。在當(dāng)前時(shí)刻,a相對(duì)滯環(huán)位置有三種情況,即滯環(huán)下側(cè),滯環(huán)內(nèi)側(cè),滯環(huán)上側(cè),如圖5所示,其中up、down分別為A相電流升、降時(shí)間。
圖5 A相電流相對(duì)滯環(huán)位置情況
表1 A相電流單周期up,down計(jì)算表
Tab.1 Calculation table of single cycle tup, tdown for phase A current
求得占空比后,采用PWM調(diào)制方式得到A相H橋逆變器的驅(qū)動(dòng)脈沖,調(diào)制原理如圖6所示。其中,ref和的關(guān)系為:ref=2–1,將調(diào)制得到的驅(qū)動(dòng)脈沖取反,可得到兩路正反互補(bǔ)PWM驅(qū)動(dòng)脈沖控制A相H橋逆變器。因FTPM-RDM可實(shí)現(xiàn)各相電流的單獨(dú)控制,故結(jié)合A相算法,可實(shí)現(xiàn)FTPM-RDM預(yù)測(cè)占空比CHBPWM閉環(huán)控制。
圖6 PWM調(diào)制方式原理圖
參照文獻(xiàn)[16]的電流重構(gòu)算法和本文FTPM-RDM的A、B、C、D、E、F六相繞組相位依次相差60°的結(jié)構(gòu)特點(diǎn),將A相繞組故障電流進(jìn)行重新分配,可獲得A相繞組故障容錯(cuò)方案。A相開(kāi)路容錯(cuò)方式為將A相繞組缺失的電流平均分成3份,由C、E兩相繞組共同補(bǔ)償1/3,D相單獨(dú)補(bǔ)償1/3,B、F兩相共同補(bǔ)償1/3;A相短路容錯(cuò)方式和開(kāi)路故障相同,但是除補(bǔ)償A相缺失電流,還要對(duì)A相短路電流進(jìn)行補(bǔ)償。
在Matlab/Simulink中,搭建基于傳統(tǒng)CHBPWM和預(yù)測(cè)占空比CHBPWM的FTPM-RDM控制系統(tǒng)仿真模型。對(duì)兩種CHBPWM控制策略在一相開(kāi)路前后及短路故障情況進(jìn)行對(duì)比仿真驗(yàn)證,設(shè)定電機(jī)轉(zhuǎn)速為300r/min,外加15N·m的負(fù)載轉(zhuǎn)矩。并對(duì)兩種CHBPWM控制策略無(wú)故障態(tài)的轉(zhuǎn)速和負(fù)載變化情況進(jìn)行對(duì)比仿真驗(yàn)證。為了驗(yàn)證預(yù)測(cè)占空比CHBPWM在實(shí)際低頻下的控制效果,仿真模型的采樣頻率取10kHz,其中FTPM-RDM參數(shù)見(jiàn)表2。
表2 永磁容錯(cuò)輪緣推進(jìn)電機(jī)主要參數(shù)
Tab.2 Main parameters of six-phase FTPM-RDM
為了量化比較兩種控制策略的性能,定義電機(jī)轉(zhuǎn)矩脈動(dòng)為
當(dāng)電機(jī)無(wú)故障穩(wěn)定運(yùn)行時(shí),在0.3s時(shí)A相發(fā)生開(kāi)路故障同時(shí)對(duì)電機(jī)施加容錯(cuò)控制策略。傳統(tǒng)CHBPWM和預(yù)測(cè)占空比CHBPWM的仿真結(jié)果分別如圖7、圖8所示。
圖8 開(kāi)路前后預(yù)測(cè)占空比CHBPWM仿真結(jié)果
通過(guò)對(duì)比圖7、圖8波形可知:
1)無(wú)故障情況下:預(yù)測(cè)占空比CHBPWM的轉(zhuǎn)矩脈動(dòng)為1.47%,B相電流諧波含量較少,電流脈動(dòng)較??;傳統(tǒng)CHBPWM的轉(zhuǎn)矩脈動(dòng)為14.13%,B相電流諧波含量較多,電流脈動(dòng)較大。
2)開(kāi)路故障情況下:預(yù)測(cè)占空比CHBPWM的轉(zhuǎn)矩脈動(dòng)為3.20%,B相電流諧波含量較少,電流脈動(dòng)較小;傳統(tǒng)CHBPWM的轉(zhuǎn)矩脈為16.07%,B相電流諧波含量較多,電流脈動(dòng)較大。
仿真結(jié)果表明:無(wú)故障和開(kāi)路故障情況下,預(yù)測(cè)占空比CHBPWM控制策略的轉(zhuǎn)矩脈動(dòng)、電流諧波畸變程度及電流脈動(dòng)均明顯小于傳統(tǒng)CHBPWM控制策略。
電機(jī)無(wú)故障穩(wěn)定運(yùn)行,在0.3s時(shí)A相發(fā)生短路故障并施加容錯(cuò)控制策略。兩種控制策略的仿真結(jié)果分別如圖9、圖10所示。
圖9 短路前后傳統(tǒng)CHBPWM仿真結(jié)果
通過(guò)對(duì)比圖9、圖10可知:短路故障情況下,預(yù)測(cè)占空比CHBPWM控制策略的電流諧波及脈動(dòng)情況明顯小于傳統(tǒng)CHBPWM控制策略。前者的轉(zhuǎn)矩脈動(dòng)為5.40%,而后者的轉(zhuǎn)矩脈動(dòng)為19.93%。因此,短路故障狀態(tài)下,本文提出的預(yù)測(cè)占空比CHBPWM控制策略優(yōu)于傳統(tǒng)的CHBPWM控制策略。
為進(jìn)一步驗(yàn)證預(yù)測(cè)占空比CHBPWM控制策略的控制效果,在電機(jī)無(wú)故障狀態(tài)下對(duì)兩種CHBPWM控制策略在不同轉(zhuǎn)速、負(fù)載情況的轉(zhuǎn)矩脈動(dòng)進(jìn)行仿真對(duì)比,仿真結(jié)果見(jiàn)表3。
表3 不同轉(zhuǎn)速、負(fù)載情況的轉(zhuǎn)矩脈動(dòng)對(duì)比
Tab.3 Torque pulsation comparison under different speed and load conditions
仿真結(jié)果表明:無(wú)故障情況下,兩種控制策略均能響應(yīng)轉(zhuǎn)速負(fù)載變化情況,預(yù)測(cè)占空比CHBPWM控制策略的轉(zhuǎn)矩脈動(dòng)明顯小于傳統(tǒng)CHBPWM控制策略。
為進(jìn)一步驗(yàn)證預(yù)測(cè)占空比CHBPWM控制策略的優(yōu)越性,搭建如圖11所示的六相永磁容錯(cuò)輪緣推進(jìn)電機(jī)實(shí)驗(yàn)平臺(tái)。電機(jī)參數(shù)和仿真參數(shù)一致,控制器采用上海遠(yuǎn)寬能源科技有限公司研發(fā)的StarSim快速控制原型,該控制器可以將Simulink編寫的控制算法下載到實(shí)時(shí)快速控制原型硬件中,實(shí)現(xiàn)對(duì)電機(jī)的快速精確控制[17]。為保證實(shí)驗(yàn)效果和仿真一致,采樣頻率設(shè)定為10kHz。
圖11 六相永磁容錯(cuò)輪緣推進(jìn)電機(jī)實(shí)驗(yàn)平臺(tái)
給定電機(jī)轉(zhuǎn)速為200r/min,負(fù)載轉(zhuǎn)矩為7N·m,電機(jī)穩(wěn)定運(yùn)行后,某一時(shí)刻發(fā)生一相開(kāi)路故障并立即啟動(dòng)容錯(cuò)控制策略,電機(jī)電流、轉(zhuǎn)矩對(duì)比響應(yīng)曲線如圖12、圖13所示。
圖12 開(kāi)路前后傳統(tǒng)CHBPWM實(shí)驗(yàn)結(jié)果
對(duì)比圖12、圖13實(shí)驗(yàn)結(jié)果可知,開(kāi)路故障前后采用預(yù)測(cè)占空比CHBPWM控制得到的實(shí)測(cè)電流波形和轉(zhuǎn)矩波形比傳統(tǒng)CHBPWM控制得到的波形精度更高。前者的電流脈動(dòng)和畸變程度明顯小于后者;前者的轉(zhuǎn)矩脈動(dòng)為17.14%,而后者的轉(zhuǎn)矩脈動(dòng)為28.57%,前者的轉(zhuǎn)矩脈動(dòng)明顯小于后者。實(shí)驗(yàn)結(jié)果表明開(kāi)路故障前后預(yù)測(cè)占空比CHBPWM控制策略的性能更好,進(jìn)一步驗(yàn)證了該控制策略的有效性。
圖13 開(kāi)路前后預(yù)測(cè)占空比CHBPWM實(shí)驗(yàn)結(jié)果
電機(jī)給定轉(zhuǎn)速為200r/min,給定負(fù)載轉(zhuǎn)矩為7N·m,電機(jī)穩(wěn)定后,某一時(shí)刻發(fā)生一相短路故障并立即啟動(dòng)容錯(cuò)控制策略,電機(jī)再次穩(wěn)定后兩種控制策略的實(shí)驗(yàn)結(jié)果分別如圖14、圖15所示。
圖14 短路故障下傳統(tǒng)CHBPWM實(shí)驗(yàn)結(jié)果
圖15 短路故障下預(yù)測(cè)占空比CHBPWM實(shí)驗(yàn)結(jié)果
對(duì)比圖14、圖15的實(shí)驗(yàn)結(jié)果可知,在短路故障下,采用預(yù)測(cè)占空比CHBPWM控制策略得到的實(shí)測(cè)電流和轉(zhuǎn)矩波形比傳統(tǒng)CHBPWM策略所得的波形效果更好。前者的電流脈動(dòng)和畸變率明顯小于后者;前者的轉(zhuǎn)矩脈動(dòng)為22.86%,后者的轉(zhuǎn)矩脈動(dòng)為42.86%,前者的轉(zhuǎn)矩脈動(dòng)明顯小于后者。實(shí)驗(yàn)結(jié)果表明短路故障下預(yù)測(cè)占空比CHBPWM控制策略的控制性能優(yōu)于傳統(tǒng)CHBPWM控制算法,進(jìn)一步驗(yàn)證了該控制算法的正確性。
本文基于FTPM-RDM獨(dú)特的H橋驅(qū)動(dòng)電路結(jié)構(gòu)特性,提出了一種預(yù)測(cè)占空比CHBPWM控制算法。仿真和實(shí)驗(yàn)結(jié)果證明,電機(jī)處在無(wú)故障、一相開(kāi)路和短路故障狀態(tài)下,本文提出的預(yù)測(cè)占空比CHBPWM控制算法在抑制轉(zhuǎn)矩脈動(dòng)、降低電流脈動(dòng)和諧波畸變等方面都具有良好的效果,解決了傳統(tǒng)CHBPWM固有的開(kāi)關(guān)頻率不固定、固定采樣頻率下控制精度低的問(wèn)題,同時(shí)保留了CHBPWM算法簡(jiǎn)單、系統(tǒng)響應(yīng)快的優(yōu)點(diǎn)。為永磁容錯(cuò)輪緣推進(jìn)電機(jī)提供了一個(gè)實(shí)際可行的控制方案。
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Predictive Duty Cycle Current Hysteresis Control for Fault-Tolerant Permanent Magnet Rim Drive Motor
Wang Zhibin Zhu Jingwei Zhao Xiyang Liu Yonghan Cao Haichuan
(School of Marine Electrical Engineering Dalian Maritime University Dalian 116026 China)
The application of fault-tolerant permanent magnet rim drive motor (FTPM-RDM) in the rim-driven thruster (RDT) can improve the space utilization and efficiency of the ship, and significantly improve the reliability of the propulsion system. In recent years, scholars have proposed direct torque control, model predictive current control and other control algorithms for FTPM-RDM, but there are problems such as complex algorithm and slow response speed. With the traditional current hysteresis band pulse width modulation (CHBPWM) control strategy, each phase winding of FTPM-RDM can be controlled separately, which has the advantages of simple algorithm and fast fault tolerant control of open-circuit and short-circuit fault. However, due to the limitation of the operation speed of the digital controller and the switching frequency allowed by the power devices, the traditional CHBPWM control strategy has the disadvantages of large current ripple and high distortion rate, resulting in large torque ripple. To solve this problem, this paper proposes a predictive duty cycle CHBPWM control strategy, which can effectively improve current control accuracy and reduce motor torque ripple while retaining the simplicity and fast response of traditional CHBPWM algorithm.
The FTPM-RDM predictive duty cycle CHBPWM control system is a dual closed-loop vector control method using an outer loop for speed and an inner loop for current. First, the error between the given speed and the actual speed is obtained through PI regulator and coordinate transformation to obtain the given value of each phase current in the static coordinate system. Then, the predicted current hysteresis width of each phase winding in the next cycle is obtained through the rotor position, electrical angular velocity and DC bus voltage of the motor at the current moment. Then, the predicted duty cycle of each phase is obtained according to the actual current relative hysteresis position to achieve the closed-loop control of the motor. At the same time, combined with fault-tolerant control strategy, one phase open and short circuit fault tolerant control of motor can be realized. This method optimizes the traditional CHBPWM control by predicting the current hysteresis width and duty cycle of a single sampling period in real time, effectively improving the control accuracy of motor phase current.
Comparing the simulation results of the two control strategies, the predicted duty cycle CHBPWM control strategy has significantly less current harmonics and pulsations than the traditional CHBPWM control strategy under the healthy, one phase open-circuit and short-circuit conditions. The torque ripple of the former is 1.47%, 3.20% and 5.40% respectively, while that of the latter is 14.13%, 16.07% and 19.93%. The torque ripple of the former is obviously smaller than that of the latter.
Comparing the experimental data of the two control strategies, the measured current waveform and torque waveform obtained by the predictive duty cycle CHBPWM control are more accurate than those obtained by the traditional CHBPWM control before and after the open-circuit fault and under the condition of one phase short-circuit fault. The current ripple and distortion degree of the former are obviously smaller than those of the latter. The torque ripple of the former is 17.14%, 22.86% respectively, and the torque ripple of the latter is 28.57%, 42.86%, The torque ripple of the former is obviously smaller than that of the latter.
The simulation and experimental results show that the predictive duty cycle CHBPWM control algorithm has a good effect in restraining the torque ripple, reducing the current ripple and harmonic distortion of the motor under the same working conditions, whether the motor is in the healthy, one phase open-circuit or short-circuit fault conditions, and solves the problem that the switching frequency of the traditional CHBPWM control algorithm is not fixed, and the control accuracy is low under the fixed sampling frequency, while retaining the advantages of the CHBPWM algorithm's simplicity and fast system response.
Fault-tolerant permanent magnet rim drive motor, H-bridge inverter circuit, predictive duty cycle, StarSim
10.19595/j.cnki.1000-6753.tces.211251
TM351
國(guó)家自然科學(xué)基金(51777024)和遼寧省自然科學(xué)基金(2020-MS-129)資助項(xiàng)目。
2021-08-11
2021-11-29
王志彬 男,1997年生,碩士研究生,研究方向?yàn)橛来湃蒎e(cuò)電機(jī)控制技術(shù)、新型電機(jī)驅(qū)動(dòng)技術(shù)等。E-mail:2830791818@qq.com
朱景偉 男,1964年生,教授,博士生導(dǎo)師,研究方向?yàn)橛来湃蒎e(cuò)電機(jī)設(shè)計(jì)及其控制技術(shù)、電力電子變換技術(shù)等。E-mail:zjwdl@dlmu.edu.cn(通信作者)
(編輯 赫蕾)