AN2357 Freescale Semiconductor / Motorola, AN2357 Datasheet - Page 6

• Manufacturer Part Number: AN2357
• Description: Sine Voltage Powered 3-Phase Permanent Magnet Motor with Hall Sensor
• Manufacturer: Freescale Semiconductor / Motorola

AN2357/D
System Concept
6
Sine Voltage Powered 3-Phase Permanent Magnet Motor with Hall Sensor
The control strategy is designed to optimally utilize features of the
MC68HC908MR8. The application provides the following properties:
Figure 5
application was designed to control a ventilator PM motor. Speed of the motor
is controlled by the amplitude of the voltage vector, while the direction of the
voltage vector depends on the rotor position. Because of the motor information,
the position is obtained only twice per electrical period. The PLL is used to
synchronize the calculated position with the actual one. The calculated position
is updated in the PWM reload at 16 kHz, while the position resolution is 2
points per period.
The PI controller is used to control the motor speed. The voltage ripple
cancellation block is independent of the dc-bus voltage. Here, controller output
is absolute voltage amplitude instead of the relative value which is input to the
sine wave generator.
The torque limitation is based on the voltage limitation. The absolute voltage
amplitude is calculated according to motor speed and required torque
limitation.
Freescale Semiconductor, Inc.
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
For More Information On This Product,
Sine voltage powered 3-phase PM synchronous motor
Position sensing using single Hall sensor
Low motor audible noise
Torque limitation
Closed speed loop
High motor efficiency
Energy recuperation with over-voltage limitation
dc-bus voltage ripple cancellation
Manual (speed pot, start-stop switch) / PC master control (RS232)
Recognition of the spinning motor after central processor unit (CPU)
reset
Deceleration control to limit over voltage during recuperation
Over-voltage protection
Over-current protection
dc-bus voltage measuring
PC master software
Memory requirements:
–
–
shows the system concept of the designed application. The
RAM — 184 bytes
FLASH — 3738 bytes
Go to: www.freescale.com
MOTOROLA
16