卡曼濾波器應用於永磁同步馬達無感測控制之研究

Abstract

永磁同步馬達近年來廣泛應用於資訊家電、自動控制、電動車輛等各種領域，是各種馬達中成長最快速的，其原因主要是具有高效率，體積小及高扭力。在某些應用如壓縮機，環境極差無法使用位置感測器(光學編碼器或霍爾元件)及負載較固定且較不要求快速響應時，無感測器的控制器便有機會使用，可以省下許多感測器的費用，更可以增加系統的信賴度。本論文利用目前已量產且廉價(低於10塊美金)的TI TMS320LF2407A 16位元DSP及搭配愛德利科技的內插式永磁同步馬達來實現無感測控制。無感測控制的方法很多，以方波馬達來說感測其反電動勢已行之有年且市場已有現成專門的微處理器及IC，而本論文是研究此最佳估測器Kalman Filter應用於弦波馬達無感測控制之可行性。 在模擬及實驗中採用了馬達於靜止座標系的動態方程式作為extended Kalman filter (EKF)使用之模型。實驗結果顯示在EKF開路時轉子位置估測值與實際值最大誤差約為20度，而速度估測可藉由調整反電勢參數得到。實驗結果也顯示了使用TMS320LF2407A執行整個估測所花費的時間不到100us，証實此顆定點DSP足以用來實現EKF於永磁弦波同步馬達無感測控制。

The number of permanent magnet synchronous motors (PMSM) is constantly growing in the industrial and automotive fields annually largely owning to their high efficiency, small size and high torque. In some applications like compressors or air conditioners, using PMSM with position sensors is extremely difficult. In other applications such as the rigorous environments where the fast response is not required, the sensorless control can be applied. TI TMS320LF2407A is adapted in this investigation owing to its low cost (i.e., less than US$10), rapid calculation (up to 40 MIPS) and the fact that it is already in mass production. The motor for the experiment comes from the AM series motor of Adlee Powertronics Co., LTD. Among the many sensorless control methods available include, the brushless DC motors (BLDCM), utilizing the zero crossing of its back EMF are the easiest and least expensive way of achieving sensorless control. In this thesis, researching the possibility of using Kalman filter with PMSM sine-wave motors is the major study issue. This investigation examines the feasibility of using Kalman filters with PMSM sine-wave motors. The motor dynamic equations in the stationary frame have been adopted for the EKF in the simulations and experiments. The experimental results reveal that the maximum error between the estimated rotor position and actual one in the steady state is 20 degrees in EKF opened-loop mode, and the estimated speed can be derived by adjusting the back EMF parameter of the dynamic equations. The results also shows that the total program execution period is less then 100us using TMS320LF2407A, and it has revealed this fixed-point DSP is capable of implementing the sinusoidal-excited sensorless control of the PMSM using the EKF theory.