AN1914 Freescale Semiconductor / Motorola, AN1914 Datasheet - Page 53

• Manufacturer Part Number: AN1914
• Description: 3-Phase BLDC Motor Control with Sensorless Back EMF Zero Crossing Detection Using DSP56F80x
• Manufacturer: Freescale Semiconductor / Motorola

11.3 Speed Setting
11.3.1 Maximal and Minimal Speed and Speed Regulator Setting
#define x_MOTOR_COMMUTATION_PREV
#define x_SPEED_ROTOR_MAX_RPM
#define x_OMEGA_MIN_SYSU
Notes: Remember that minimal angular speed is not in radians, but in system units where 32768 is the
#define PER_SPEED_SAMPLE_S 0.001
#define x_SPEED_PI_PROPORTIONAL_GAIN
#define x_SPEED_PI_PROPORTIONAL_GAIN_SCALE
#define x_SPEED_PI_INTEGRAL_GAIN
#define x_SPEED_PI_INTEGRAL_GAIN_SCALE
Notes:
All this section settings are in bldcadczcdefines.h.
In order to compute the speed setting, it is important to set the number of BLDC motor commutations
per motor mechanical revolution:
Maximal required speed in rpm is set by:
If you also request to change the minimal motor speed, then you need to set minimal angular speed:
The speed PI regulator constants can be tuned as described below. All settings can be found in
bldcadczcdefines.h.
The execution period of the speed controller is set by:
Both proportional and integral gain have two coefficients: portion and scale.
Speed Proportional gain:
Speed Integral gain:
The PI controller proportional and integral constants can be set experimentally.
The
x_SPEED_PI_INTEGRAL_TI_REAL) are not directly used for regulator setting, but can be used to
calculate
x_SPEED_PI_INTEGRAL_GAIN,
comments.
maximal speed done by
If the motor has problems when requested speed is changed, then it is recommended to slow
down the regulator. If the yy_GAIN_SCALE is increased, the gain is decreased.
x_SPEED_PI_PROPORTIONAL_GAIN,
coefficients
DSP56F80x MC PWM Module in Motor Control Applications
Freescale Semiconductor, Inc.
For More Information On This Product,
x_SPEED_ROTOR_MAX_RPM
x_SPEED_PI_INTEGRAL_GAIN_SCALE
Go to: www.freescale.com
x_SPEED_PI_PROPORTIONAL_GAIN_REAL
3000
4096
18
/* Sampling Period of the Speed Controller [s] */
/* angular frequency minimal [system unit] */
/* Motor Commutations Per Revolution */
/* maximal rotor speed [rpm] */
22000 /* speed proportional gain portion*/
27500 /* speed integral gain portion */
19 /* speed proportional gain scale*/
23 /* speed integralgain gain scale */
x_SPEED_PI_PROPORTIONAL_GAIN_SCALE
Setting of SW parameters for other motor kits
) using the formulae in the
(resp.
(resp.
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