SLLSFV1 March 2025 MCF8329A-Q1
PRODUCTION DATA
The input control signal can be motor speed, DC input power or motor voltage (motor PWM duty cycle) as configured by CLOSED_LOOP_MODE and CONST_POWER_MODE bits.
Speed Input Transfer Function
Figure 6-11 shows the relationship between DUTY CMD and SPEED REF. When speed loop is enabled, DUTY CMD sets the SPEED REF in Hz. MAX_SPEED sets the SPEED REF at DUTY CMD of 100%. MIN_DUTY sets the minimum SPEED REF (MIN_DUTY x MAX_SPEED). If MAX_SPEED is set to 0, SPEED REF is clamped to zero (irrespective of DUTY CMD) and motor is in stopped state.
Power Input Transfer Function
Figure 6-12 shows the relationship between DUTY CMD and POWER REF. When power loop is enabled, DUTY CMD sets the POWER REF in Watt. MAX_POWER sets the POWER REF at DUTY CMD of 100%. MIN_DUTY sets the minimum POWER REF (MIN_DUTY x MAX_POWER). If MAX_POWER is set to 0, POWER REF is clamped to zero (irrespective of DUTY CMD) and motor is in stopped state.
Current Input Transfer Function
Figure 6-13 shows the relationship between DUTY_CMD and CURRENT_REF. When the current loop is enabled, DUTY_CMD sets the q-axis CURRENT_REF (iq_ref)in Ampere. MAX_CURRENT is the same as ILIMIT and sets the CURRENT_REF at DUTY CMD of 100%. MIN_DUTY sets the minimum CURRENT_REF (MIN_DUTY x MAX_CURRENT).
Modulation Index Input Transfer Function
In modulation index control mode, the voltage applied to the motor (direct axis component of modulation index Vd and quadrature axis component of modulation index Vq) is proportional to the DUTY_CMD (from MIN_DUTY to 100% PWM duty applied to motor). For DUTY CMD less than MIN_DUTY, the applied voltage to the motor is clamped to zero by making the duty cycle to zero.