AN1362 STMicroelectronics, AN1362 Datasheet - Page 8

• Manufacturer Part Number: AN1362
• Description: SWITCHED RELUCTANCE MOTOR CONTROL BY ST FIVE
• Manufacturer: STMicroelectronics

AN1362
no logic combinations of the encoder to perform both the right pre-phase firing sequence and the timing,
in order to obtain a speed higher than the previous one.
The expected speed can be reached only by using a specific Timer peripheral to switch off the phase in
advance. The Interrupt routine at high speed turns the phase off after that the logical function turns it on.
This function is performed inside the Timer1 Interrupt, which turns off the phase by using the right element
of a Table (The Visual FIVE L.U.T.) pointed by the variable “pointer” inside the PWM_0_COUNT. The
Timer1 configuration will be changed after the soft-start phase, by using the same peripheral both for soft
start and high-speed algorithm, saving resources for the other functions. The right value of the “pointer” is
reached after measuring the encoder inside Timer_0 Interrupt routine.
In order to understand the algorithm, the flow chart is showed below, and the assembler file is found in the
enclosure (appendix 2).
Figure 9. MAIN PROCEDURE
Figure 10. ANALYZE PROCEDURE
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Encoders
Encoders
Reading
Reading
(no pre-phase)
Low Speed
configuration and initialization
Filtering Data
Filtering Data
Peripheral and Variables
Start Current
Procedure
Procedure
Start up
Analyze
Phase
Firing
Mode
Mode
Driving Signal
Driving Signal
Generation
Generation
Enable TIM1 INT
Start Pre-phase
High Speed
EXIT
EXIT