| Summary: | 碩士 === 國立交通大學 === 電機與控制工程系所 === 94 === This thesis presents the design and implementation of a sensors or sensorless speed control IC for permanent magnet synchronous motors (PMSMs). By using the hierarchical and modular realization strategy, the designed circuit can be re-used to reduce the design complexity and the total gate counts for optimum design. Two methodologies are presented: 1) a speed control architecture employing linear Hall effect sensors, and 2) a sensorless speed control scheme with a flux-based rotor position estimation algorithm. By using linear Hall effect sensors, the rotor position information can be obtained, and flux-oriented control (FOC) is achieved. On the other hand, the sensorless algorithm uses the incremental values of flux linkage and the normalized back-EMF functions to estimate incremental rotor position. An internal closed-loop correction mechanism within this algorithm can correct rotor position estimation drift, which could due to quantization error of digital processing or measurement noise. Mathematical analyses and numerical simulations demonstrate robustness of this sensorless algorithm. However, motor parameter variations and measurement inaccuracies still introduce rotor position estimation error. Sensitivity analyses to motor parameters and measured signals are also presented. According to this flux-based sensorless approach, a new algorithm is proposed. The estimated back-EMF peak value is involved in the new algorithm as an additional parameter. By tuning the weighting of the new parameter, better performance than the original algorithm’s can be obtained. By using ModelSim/Simulink/PSIM, the system-level simulation can be achieved and the influence of sampling rate on speed error is also presented. All registers in the proposed control IC can be observed via the JTAG download cable. An experimental platform has been constructed and results are given for verification.
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