The FAST unified observer structure
exploits the similarities between all motors that use magnetic flux for energy
transduction:
- Supports both synchronous
(BLDC, SPM, IPM), and asynchronous (ACIM) control.
- Provides salient compensation
for interior permanent magnet motors: observer tracks rotor flux and angle
correctly when Ls-d and Ls-q are provided.
FAST offers unique, high-quality motor
feedback signals for control systems:
- High-quality Flux signal for
stable flux monitoring and field weakening.
- Superior rotor flux Angle
estimation accuracy over wider speed range compared to traditional observer
techniques independent of all rotor parameters for ACIM.
- Real-time low-noise motor
shaft Speed signal.
- Accurate high-bandwidth
Torque signal for load monitoring and imbalance detection.
FAST replaces mechanical encoders and
resolvers and accelerates control system design:
- Angle estimator converges
within first cycle of the applied waveform, regardless of speed.
- Stable operation in all power
quadrants, including generator quadrants.
- Accurate angle estimation at
steady state speeds below 1 Hz (typ) with full torque.
- Angle integrity maintained
even during slow speed reversals through zero speed.
- Angle integrity maintained
during stall conditions, enabling smooth stall recovery.
- Motor identification measures
required electrical motor parameters of unloaded motor in under 2 minutes
(typ).
- On-the-fly stator
resistance recalibration (online Rs) tracks stator resistance changes in
real time, resulting in robust operation over temperature. This feature can
also be used as a temperature sensor of the motor's windings (basepoint
calibration required).
- Superior transient response
of rotor flux angle tracking compared to traditional observers.
- PowerWarp™ software
adaptively reduces current consumption to minimize the combined (rotor and
stator) copper losses to the lowest, without compromising ACIM output power
levels.