SPRUHJ1I January 2013 – October 2021 TMS320F2802-Q1 , TMS320F28026-Q1 , TMS320F28026F , TMS320F28027-Q1 , TMS320F28027F , TMS320F28027F-Q1 , TMS320F28052-Q1 , TMS320F28052F , TMS320F28052F-Q1 , TMS320F28052M , TMS320F28052M-Q1 , TMS320F28054-Q1 , TMS320F28054F , TMS320F28054F-Q1 , TMS320F28054M , TMS320F28054M-Q1 , TMS320F2806-Q1 , TMS320F28062-Q1 , TMS320F28062F , TMS320F28062F-Q1 , TMS320F28068F , TMS320F28068M , TMS320F28069-Q1 , TMS320F28069F , TMS320F28069F-Q1 , TMS320F28069M , TMS320F28069M-Q1
Topic | Typical Software Sensors and FOC Solutions |
FAST Estimator and InstaSPIN-FOC Solution |
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Electrical Motor Parameters | Motor-model based observers heavily dependent on motor parameters | Relies on fewer motor parameters. Off-line parameter identification of motor – no data sheet required. On-line parameter monitoring and re-estimation of stator resistance. |
Estimator Tuning | Complex observer tuning done multiple times for speed/loads for each motor | No estimator tuning required. Once motor parameters are identified, it works the same way every time across speed/torque dynamics. |
Estimator Accuracy | Angle-tracking performance is typically only good at over 5-10Hz with challenges at higher speeds and compensation for field weakening; Dynamic performance influenced by hand tuning of observer; Motor stalls typically crash observer | FAST provides reliable angle tracking that converges within one electrical cycle of the applied waveform, and can track at less than 1-Hz frequency (dependent on quality and resolution of analog sensing). Angle tracking exhibits excellent transient response (even with sudden load transients that can stall the motor, thus enabling a controlled restart with full torque). |
Start-up | Difficult or impossible to start from zero speedObserver feedback at zero speed is not stable, resulting in poor rotor angle accuracy and speed feedback | InstaSPIN-FOC includes:
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Current Loop | Tuning FOC current control is challenging – especially for novices | Automatically sets the initial tuning of current controllers based on the parameters identified. User may update gains or use own controllers if desired. The identification process to fully tune the observer and torque controller takes less than 2 minutes. |
Feedback Signals | System offsets and drifts are not managed | FAST includes automatic hardware/software calibration and offset compensation. FAST requires 2-phase currents (3 for 100% and over-modulation), 3-phase voltages to support full dynamic performance, DCbus voltage for ripple compensation in current controllers FAST includes an on-line stator resistance tracking algorithm. |
Motor Types | Multiple techniques for multiple motors: standard back-EMF, Sliding Mode, Saliency tracking, induction flux estimators, or “mixed mode” observers | FAST works with all 3-phase motor types, synchronous and asynchronous, regardless of load dynamics. Supports salient IPM motors with different Ls-d and Ls-qIncludes PowerWarp for induction motors = energy savings. |
Field-Weakening | Field-weakening region challenging for observers – as Back-EMF signals grow too large, tracking and stability effected | FAST estimator allows easy field weakening or field boosting applications due to the stability of the flux estimation in a wide range. |
Motor Temperature | Angle tracking degrades with stator temperature changes | Angle estimation accuracy is improved from online stator resistance recalibration. |
Speed Estimation | Poor speed estimation causes efficiency losses in the FOC system and less stable dynamic operation | High quality low noise Speed estimator, includes slip calculation for induction motors. |
Torque Estimation | Torque and vibration sensors typically required | High bandwidth motor Torque estimator. |