标题: 永磁无刷马达使用霍尔感测器或无感测之数位控制器设计
Design of a Digital Controller for PM Brushless Motors with or without Hall Sensors
作者: 张晏铨
Yen-Chuan Chang
邹应屿
Ying-Yu Tzou
电控工程研究所
关键字: 数位伺服控制IC;永磁同步马达;线性型霍尔元件;无感测控制;无感测启动;digital ac servo IC;permanent magnet synchronous motor;linear Hall sensor;sensorless control;sensorless startup
公开日期: 2006
摘要: 本论文呈现永磁无刷马达使用霍尔感测器或无感测之数位控制器设计,藉由使用线性型霍尔感测器实现一低成本之数位马达控制IC。线性型霍尔感测器讯号可做为转子绝对位置之参考,产生速度之回授讯号,并直接在三轴静止座标产生各相电流命令,达到磁场导向控制目的,而不需透过静止三轴与同步旋转二轴间的座标转换。此外,此IC亦实现一无感测之演算法,藉由估测之磁通链增量与反抗电动势峰值可估测转子角度变化量,此无感测演算法对于因数位化处理的量化误差,以及回授讯号的杂讯所造的转子角度估测误差具有内回路的自动修正机制。本文所设计之控制IC采用阶层式、模组化的设计方式,IC内每个功能方块皆具有可程式化之特点,可透过外部通讯介面调整各方块功能与设定参数以配合不同应用,与传统数位讯号处理器与微控器相比,使用者可免去复杂之软体设计步骤,减少开发时程。本文并以现场可程式化的闸阵列(Filed Programmable Gate Array, FPGA)实现验证了此IC之可行性与效能。
本论文亦提出一个无刷马达之新型启动方法,可避免无感测启动时产生反转之情形。此方法可在马达静止时侦测出马达转子初始位置,再以一特殊之方法加速马达,直到反抗电动势大小足以提供无感测演算法正确的估测转子位置,便可切换到无感测驱动模式。与传统方法比较,此方法仅需回授直流链电流,不需要额外的位置感测器,可降低成本,且其转子估测方式与马达参数无关,具有高强健度,初始位置估测之解析度为30度电气角。为了验证此方法之可行性,本文利用一颗数位讯号处理器(TMS320LF2407A)实现所提出的新型启动控制方法。
This thesis presents the design of a digital controller for PM brushless motors with or without Hall sensors. By using linear Hall sensors, a digital motor control IC is implemented for low-cost motion control applications. The absolute rotor position information can be obtained and a speed estimator is devised to generate speed feedback for the servo loop compensator. The field-oriented torque control is achieved by generating current references in the three-phase stationary frame without the stationary-to-rotating reference frame transformation and its reverse. Besides, a sensorless algorithm is also implemented. Based on the estimated three-phase flux-linkage increments and the estimated peak back-EMF value, the rotor position incremental can be estimated with a weighted-sum approach. An internal closed-loop correction mechanism within this algorithm can automatically correct the rotor position estimation drift, which could be resulted by the quantization error, circuit nonlinearities, and sampling noises. The control IC is realized using hierarchical and modular realization strategy, each functional block for the digital control IC is designed as a reusable IP with FPGA implementation. The digital sensorless IC is configurable with its modular blocks and is programmable with its control registers via a serial interface to fit various applications without complicated software programming as realized by using conventional DSP or microcontrollers. Experiment results are presented to verify the performance and feasibility of the proposed IC.
The thesis also presents a new sensorless starting method for brushless DC motors without reversing rotation for unidirectional applications. The method can detect the rotor position at standstill and a specific start-up method is then used to accelerate the motor up to middle-speed where conventional sensorless control algorithms based on the back-EMF can work properly. The proposed scheme employs only one current sensor at DC-link side of the inverter, and can be applied to a motor without knowing its parameters and additional position sensors. As compared with previous approaches, the presented technique can simplify the sensorless position detection procedure and lower the cost. The proposed initial rotor position detection technique has a resolution of 30 electrical degrees, and does not cause any rotor vibration during the detection process. The sensorless starting scheme has been implemented on a single-chip DSP controller (TMS320LF2407A) and experimental results reveal that the starting procedure can work smoothly without temporary reversing rotation.
URI: http://140.113.39.130/cdrfb3/record/nctu/#GT009412583
http://hdl.handle.net/11536/80717
显示于类别:Thesis