無刷直流馬達無感測換相控制IC之規劃與設計

Abstract

本論文以混合訊號積體電路設計的技術，設計與規劃應用於無刷直流馬達的無感測換相控制IC，目的是為了設計一顆不需霍爾元件回授信號仍可進行無刷直流馬達速度控制的IC。此顆IC採用端電壓量測方式的無感測換相控制技術，藉由偵測未激發相反抗電動勢的零交越點，估算馬達的換相時刻。控制IC的架構主要包含換相偵測電路與換相控制電路，換相偵測電路以類比電路的方式實現，其核心為餘值放大器、比較器及多工器，目的是為了產生正確的零交越訊號；換相控制電路，以數位電路方式實現，可實現可程式化的換相控制功能，所設計的數位式相位移器，具有8種可程式化的相位補償角，可以修正輸入濾波器所造成的相位落後，降低換相誤差。本論文所設計的無感測換相控制IC採用開迴路啟動的方法，同時內建速度估測的機制，設計流程是先以PSIM軟體模擬動態速度估測效果，進而分析速度估測演算法的可行性，最後再以晶片實現。本論文說明了無刷直流馬達換相控制IC的類比及數位電路的設計方法，發展了類比換相偵測電路的IC智權，完成了換相控制電路的電腦輔助設計與模擬驗證，並實際以一個DVD主軸馬達控制CPLD IC設計平台完成功能驗證。

This thesis presents the plan and design of a sensorless commutation control IC using mixed-signal technology for brushless DC motors (BLDCM). The goal is to design a sensorless BLDCM control IC without using the Hall sensors. Back emf method using the terminal voltage sensing is adopted for the detection of the commutation instants for the proper commutation control of the BLDCM. The control IC contains a commutation detection circuit and commutation control circuit. The commutation detection circuit is designed using analog IC design technique and it consists of a residue amplifier, a comparator, and a multiplexer to generate correct commutation signals. The commutation control circuit is designed using digital IC design technique and it is realized by using CPLD for functional verification. A frequency independent digital phase shifter containing eight programmable phase-lag angles has been designed, which can be used to compensate the phase lag due to the back emf filtering. Open-loop control with programmable ramp control has been used for the start-up control of the design sensorless commutation control IC. The designed IC also contains a speed estimator and a PI compensator. This paper presents a detailed design procedure for the design of a motor control IC using both analog and digital design techniques. Analog intellectual properties (IP) of the BLDCM sensorless commutation IC have been developed. The proposed design scheme has been first verified by using computer simulation and then by a CPLD-based DVD spindle motor control IC development platform.