| Along with the development of motor-control technology, power electronic technology, technology of micro-electronics and high-performance permanent-magnet materials a new-style motor -- BLDCM(Brushless Direct Current Motor) rised up. The BLDCM is characterised by replacing mechanical commutator with electronic commutator. It has low acoustic noise and fast dynamic response. Moreover, it has high power density with high proportion of torch to inertia in spite of small size drive. So it has a wide application in spaceflight, war industry, digital control, metallurgy, medical appliance etc. Traditional BLDCM controller often uses MPU such as MCS-51, which has low efficiency and needs more instruction cycles to execute multiplication or division. To achieve better performance and higher efficiency of BLDCM, a high performance low power-dissipation ARM(Advanced RISC Machines) processor S3C44B0X is introduced to the circuit as the core of the controller. The design abandoned some peripheral circuit to make it more simple and digital. In addition, an embedded real-time operating system --μC/OS-Ⅱis applied, which makes the control more precise, more real time.In fact, as far as hardware is concerned, it pay more attention to isolation of signal, drive circuit, protection of low voltage of battery and protection of current overload of circuit(including main circuit and motor circuit) etc. In software part, it mainly consideres the way that analog signals of AD converter is collected, interrupt process, PID arithmetic and generation of PWM signals etc. Most figures of hardware design is introduced as well as the major part of software project.Firstly it presents the relationship between embedded system and ARM, introduces characteristics of S3C44B0X and explains whyμC/OS-Ⅱis chosen. Then it introduces BLDCM and its control method. It amply analyses designs of hardware and software in succession. At last it makes conclusion and brings forward work emphasis for the future.
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