AN1857 Freescale Semiconductor / Motorola, AN1857 Datasheet - Page 20

• Manufacturer Part Number: AN1857
• Description: A 3-Phase ac Induction Motor Control System Based on the MC68HC908MR32
• Manufacturer: Freescale Semiconductor / Motorola

Application Note
Power Stage
20
For a more detailed description of the 3-phase ac BLDC high-voltage
power stage, refer to the Motorola Embedded Motion Control Series
3-Phase BLDC High-Voltage Power Stage User’s Manual, Motorola
document order number MEMC3PBLDCPSUM/D.
The function of the power stage is to provide the high-power drive
circuitry for various types of motors. The power stage is suitable for
driving ac induction, permanent magnet, and brush and brushless dc
motors.
The power stage consists of a set of two printed circuit boards (PCB).
One of the PCBs is a power module, containing power IGBTs (insulated
gate bipolar transistors), a brake IGBT, a power factor corrector FET
(field-effect transistor), and temperature-sensing diodes. The second
PCB contains IGBT drive circuits, analog signal conditioning, low-
voltage power supplies, power factor control circuitry, and an
MC68HC705JJ7 microcontroller used for board configuration and
identification.
module.
Power module features include:
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Freescale Semiconductor, Inc.
For More Information On This Product,
1-phase bridge rectifier
Power factor switch and diode
dc-bus brake IGBT and brake current limiting resistors
3-phase bridge inverter (six IGBTs)
Individual phase and dc bus current sensing shunt resistors with
Kelvin connections
Power stage temperature sensing diodes
IGBT gate drivers
Current and temperature signal conditioning
3-phase back-EMF voltage sensing and zero cross detection
circuitry
Board identification processor (MC68HC705JJ7)
Low-voltage on-board power supplies
Cooling fans
Go to: www.freescale.com
Figure 11
shows a complete block diagram of the power
MOTOROLA
AN1857