永磁伺服馬達之自動切換式Fuzzy/Lead-Lag控制器設計

Abstract

電流回路為伺服馬達控制架構最內層的控制回路，為伺服控制系統的核心所在。本研究從電流回路著手，藉由Medium Filter降低PWM切換雜訊和環境雜訊對電流回授信號的影響，進而使電流回路控制效能更佳，架構外層的速度回路時，將獲得較佳且較穩定的工作效能。研究探討速度回路線性與非線性的工作區間，並設計相位領先-落後補償器 (線性控制器)，使系統在線性工作區得到較好的工作效能；而在非線性工作條件時，則設計模糊控制器(非線性控制器)克服系統的非線性特性，使系統達到較佳的控制效能。最後整合線性與非線性控制器的優點，設計自動切換式模糊與相位領先-落後控制器，使得伺服馬達於各種不同的工作條件，即使落入電流飽和之非線性區間，皆能擁有較佳的工作效能。硬體方面本研究採用德州儀器公司的TMS320 F2812 DSP作為控制晶片。實驗結果指出，在不同慣性負載及不同轉速測試條件下，本研究所設計的控制器均明顯改善了伺服馬達的系統頻寬及控制的穩定性。

In this thesis, a novel fuzzy/lead-lag switching control design is developed for the permanent magnetic (PM) DC brushless motor to improve its velocity response performance in both the bandwidth and stability. In the current feedback loop, the noise due to the Hall sensor, PWM switching, and environments has been practically reduced by applying the proposed medium filter and its velocity performance is significantly improved. Furthermore, to improve performance and stability of the velocity loop, both operations in linear and nonlinear ranges are concerned. In the linear operation region, the lead-lag compensator has been designed to effectively increase the bandwidth. On the other hand, the fuzzy controller has been designed to be more efficient in the nonlinear range due to the saturated current, the larger operation range, or significant load variation. Finally, the auto-switching fuzzy/lead-lag controller is designed by integrating two controllers to properly operate in various regions with a proper switching rule. The present controller is implemented on the TI TMS320 F2812 DSP and experimental results indicate that the proposed controller significantly improves both system bandwidth and response performance in the overshoot and steady-state oscillation under various conditions.