1. 感應馬達/永磁馬達的自學習(Auto-tuning)技術
Auto-tuning technology of induction motor/permanent-magnet motor
使用演算法自動取得感應馬達或永磁馬達的電機參數, 對感應馬達來說, 即為定子電阻, 轉子電阻, 互感, 漏感等參數, 而對永磁馬達來說, 即為定子電阻,d軸電感, q軸電感與反電動勢常數等參數。這些參數的精確度則決定驅動器的控制性能, 因此設計精確估測馬達參數的自學習功能對驅動器來說已是不可或缺的。
Use algorithm to obtain motor parameters of induction motor or permanent-magnet motor automatically. Parameters for induction motor include stator resistance, rotor resistance, mutual inductance and leakage inductance; and for permanent-magnet motor, parameters are stator resistance, inductance of d axle and q axle, as well as back E.M.F. constant. The accuracy of these parameters determines control performance of driver; therefore, it is indispensable to a driver to design self-learning function which can accurately estimate motor parameters.
2. 磁場導向(FOC)驅動器設計 Field-oriented control (FOC) driver design
使用定點數(Fixed-point)實現感應馬達/永磁馬達的磁場導向驅動器韌體設計, 電流回授透過d,q軸轉換, 先設計電流回路(內回路), 確保電流回路頻寬與性能符合規格要求, 再設計速度回路(外回路), 而電流回路性能取決於馬達電機參數, 而速度回路性能則取決於馬達機械參數, 因此磁場導向若要有高性能的表垷, 則取決於馬達參數估測的精確性。
Use fixed-point to realize firmware design for field-oriented control driver of induction motor/permanent-magnet motor. Current feedback is converted by d, q axles. Design current circuit (internal circuit) first to ensure bandwidth and performance of current circuit meet specification; then design speed circuit (external circuit). The performance of current circuit depends on motor parameters while speed circuit relies on motor mechanical parameters. Therefore, high performance of field-oriented control depends upon accuracy of motor parameter estimation.
3. 永磁馬達sensorless控制 Sensorless control of permanent-magnet motor
不使用位置回授感測器來驗動永磁馬達的技術即為永磁馬達sensorless控制, 可以用反電動勢法, model-based或是高頻注入的方式, 取得轉子位置資訊, 一般來說, 反電動勢法都能夠達到1:20的速控比, 但是在低於速控比的速度下, 可能就使用其它方式(I/F)來將馬達帶起來。而目前使用model-based或高頻注入的方式可以達到更高的速控比, 在某些應用上(如風機, 水泵, 或壓縮機), 本技術具有很大的成本優勢。
Permanent-magnet motor sensorless control is a technology which does not employ position feedback sensor to test permanent-magnet motor. Back-EMF, model-based or high frequency injection are used to obtain rotor position. Generally, back-EMF is able to reach 1:20 speed control ratio; but under speed that is lower than speed control ratio, another method (I/F) may be used to drive the motor. Model-based or high frequency injection currently used can reach higher speed control ratio. In some applications (such as air blower, water pump or compressor), this technology has great cost advantage.
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