AN1910 Freescale Semiconductor / Motorola, AN1910 Datasheet - Page 16

• Manufacturer Part Number: AN1910
• Description: 3-Phase AC Motor Control with V/Hz Speed Closed Loop Using the DSP56F80X
• Manufacturer: Freescale Semiconductor / Motorola

Software Design
16
The process that is performed in PWM reload callback function: pwm_Reload_A_ISR is accessed
regularly at the rate given by the set PWM reload frequency. This process is repeated often enough to
compare it to the wave frequency. Wave length comparisons are made to generate the correct wave
shape. Therefore, for 16kHz PWM frequency, it is called each 4th PWM pulse, thus the PWM registers
are updated in 4kHz rate (each 250 sec).
Figure 6-5
Amplitude is 1 (100%).
Figure 6-6
Amplitude is 0.5 (50%).
Figure 6-5. 3-ph Sine Waves with 3rd Harmonic Injection, Amplitude = 100%

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defines the dutycycles generated by the mcgen3PhWaveSine3rdHIntp function when
shows the dutycycles generated by the mcgen3PhWaveSine3rdHIntp function when
3-Phase AC Motor Control with V/Hz Speed Closed Loop
Freescale Semiconductor, Inc.
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