Embedded Software and Motor Control Libraries for PXR40xx

Function GFLIB_ControllerPIpAW_F32
The sum of the scaled proportional and integral terms gives a complete equation of the
controller. The problem is however, that either of the gain parameters K P_sc, K I_sc can
be out of the [-1, 1) range, hence can not be directly interpreted as fractional values. To
overcome this, it is necessary to scale these gain parameters using the shift values as
follows:
where
Equation GFLIB_ControllerPIpAW_Eq9
Equation GFLIB_ControllerPIpAW_Eq10
• f16PropGain - is the scaled value of proportional gain [-1, 1)
• s16PropGainShift - is the scaling shift for proportional gain [-31, 31)
• f16IntegGain - is the scaled value of integral gain [-1, 1)
• s16IntegGainShift - is the scaling shift for integral gain [-31, 31)
The sum of the scaled proportional and integral terms gives a complete equation of the
controller:
Equation GFLIB_ControllerPIpAW_Eq11
The output signal limitation is implemented in this controller. The actual output u(k) is
bounded not to exceed the given limit values f32UpperLimit, f32LowerLimit. This is due
to either the bounded power of the actuator or to the physical constraints of the plant.
Equation GFLIB_ControllerPIpAW_Eq12
Embedded Software and Motor Control Libraries for PXR40xx, Rev. 1.0
282 Freescale Semiconductor, Inc.