基于分數(shù)階滑模觀測器的永磁同步電機無傳感器矢量控制

何克勝 王英

摘 要：為解決基于傳統(tǒng)滑模觀測器的永磁同步電機轉(zhuǎn)速和位置估計精度不高以及抖振過大等問題，設計了一種分數(shù)階滑模觀測器。首先根據(jù)分數(shù)階理論提出一種分數(shù)階滑模趨近律，并證明其穩(wěn)定性；然后將永磁同步電機的定子實際電流與估計電流的差值作為滑模面，利用分數(shù)階滑模趨近律設計滑模觀測器的控制律，獲取反電動勢后采用鎖相環(huán)提取轉(zhuǎn)速和位置；最后建立了永磁同步電機無傳感器矢量控制的仿真模型。仿真結(jié)果顯示新型分數(shù)階滑模觀測器不僅靜態(tài)性能好，而且與基于指數(shù)趨近律設計的滑模觀測器相比，具有動態(tài)跟蹤速度快、觀測精度高、抖振小等優(yōu)點。

關(guān)鍵詞：永磁同步電機；分數(shù)階；滑模趨近律；滑模觀測器；矢量控制

中圖分類號：TM341 文獻標識碼：A

Abstract： In order to solve the problem that the traditional sliding mode observer speed and position estimation accuracy is not high and the chattering is too large，a fractional sliding mode observer is designed.Firstly，According to the fractional theory ，a fractional sliding mode reaching law is designed and its stability is proved.Then，the difference between the actual current and the estimated current is taken as the sliding surface.The control law of the sliding mode observer is designed by the fractional-order sliding mode reaching law.After obtaining the back electromotive force，the rotational speed and position are extracted by the phase locked loop.Finally，the simulation model of permanent magnet synchronous motor is established by using phase-locked loop.The simulation results show that the new fractional order sliding mode observer has good static performance.And compared with the sliding mode observer based on the exponential reaching law，it has the advantages of fast tracking speed，high observation accuracy and small chattering.

Key words： permanent magnet synchronous motor（PMSM）；fractional order；sliding mode reaching law；sliding mode observer；vector control

1 引 言

近年來，永磁同步電機（permanent magnet synchronous motor，PMSM）由于其具有體積小、結(jié)構(gòu)簡單、功率密度高、可靠性高等優(yōu)點，被廣泛應用在船舶、電動汽車、數(shù)控機床等領(lǐng)域。在永磁同步電機常用的矢量控制策略中，為獲得高精度的控制效果，需要獲取電機的轉(zhuǎn)子位置和速度信息。而傳統(tǒng)的機械傳感器受到工作環(huán)境的影響和控制成本的考慮，無傳感器控制技術(shù)研究正在逐漸的成為熱

門[1]。其中滑模觀測器其算法簡單、易實現(xiàn)，使系統(tǒng)狀態(tài)不受外部擾動和原有參數(shù)變化的影響，具有很強的魯棒性，是一種很好的無傳感器控制方法。然而滑模觀測器中的切換函數(shù)，會使系統(tǒng)產(chǎn)生抖振現(xiàn)象，進而影響到觀測精度，需要對其進行改進。……