AN1931D Freescale Semiconductor / Motorola, AN1931D Datasheet - Page 4

• Manufacturer Part Number: AN1931D
• Description: 3-Phase PM Synchronous Motor Vector Control
• Manufacturer: Freescale Semiconductor / Motorola

Target Motor Theory
3.
3.1 Permanent Magnet Synchronous Motor
4
The PM synchronous motor vector control application utilizes four channels of the Quadrature Timer
module for position and speed sensing. A fifth channel of the Quadrature Timer module is set to
generate a time base for speed sensing and a speed controller.
The Quadrature Decoder is a module providing decoding of position signals from a Quadrature
Encoder mounted on a motor shaft. It has the following features:
The PM synchronous motor vector control application utilizes the Quadrature Decoder connected to Quad
Timer module A. It uses the decoder’s digital input filter to filter the encoder’s signals, but does not make
use of its decoding functions, freeing the decoder’s digital processing capabilities to be used by another
application.
The PM synchronous motor is a rotating electric machine with a classic 3-phase stator like that of an
induction motor; the rotor has surface-mounted permanent magnets (see
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Target Motor Theory
Each timer module consists of four 16-bit counters/timers
Count up/down
Counters are cascadable
Programmable count modulo
Maximum count rate equals peripheral clock/2 when counting external events
Maximum count rate equals peripheral clock when using internal clocks
Count once or repeatedly
Counters are preloadable
Counters can share available input pins
Each counter has a separate prescaler
Each counter has capture and compare capability
Includes logic to decode quadrature signals
Configurable digital filter for inputs
32-bit position counter
16-bit position difference counter
Maximum count frequency equals the peripheral clock rate
Position counter can be initialized by software or external events
Preloadable 16-bit revolution counter
Inputs can be connected to a general purpose timer to aid low speed velocity.
Freescale Semiconductor, Inc.
3-Phase PM Synchronous Motor Vector Control
For More Information On This Product,
Go to: www.freescale.com
Figure
3-1).
MOTOROLA