Speed Controller (AC)
Implement speed controller model for vector controlled AC motor drives
Library
Simscape / Electrical / Specialized Power Systems / Electric Drives / Fundamental Drive Blocks
Description
The Speed Controller (AC) block represents a PI speed regulator model for AC machines used in vector-controlled drives. It has two operating instances: the first with both torque and flux references outputs and the second with torque reference output only. The models of the first and second instances are shown in the figures.
Parameters
Controller Tab
- Controller type
Specify the type of controller to use:
With flux reference output(default)Without flux reference output
- Regulation type
Specify the type of regulation to use:
Speed regulation(default)Tourqe regulation
- Base sample time (s)
The time step used for the simulation, in seconds. The default value is
2e-6.- Speed reference ramp (rpm/s) [Deceleration, Acceleration]
The maximum rate of change of the speed reference, in rpm/s, to keep the machine's currents within rated values. This parameter is required and enabled only if the Regulation type parameter is set to
Speed regulation. The default value is[-1800,1800].- Proportional gain
The PI controller's proportional gain. This parameter is required and available only if the Regulation type parameter is set to
Speed regulation. The default value is5.- Integral gain
The PI controller's integral gain. This parameter is required and available only if the Regulation type parameter is set to
Speed regulation. The default value is10.- Low-pass filter cutoff frequency (Hz)
The speed measurement first-order filter cutoff frequency, in hertz. This parameter is required and available only if the Regulation type parameter is set to
Speed regulation. The default value is100.- Output torque saturation (N.m) [Negative, Positive]
The minimum (negative) and maximum (positive) torque reference output limits, in newton-meter. The default value is
[-17.8,17.8].- Sample time (s)
The speed-controller sampling time, in seconds. The sampling time must be a multiple of the simulation time step. The default value is
100e-6.
Machine Tab
- Nominal frequency (Hz)
The nominal frequency of the machine, in hertz. This parameter is required and available only if the Speed controller type parameter is set to
With flux reference output. The default value is60.- Pairs of poles
The number of pole pairs. This parameter is required and available only if the Speed controller type parameter is set to
With flux reference output. The default value is2.- Nominal flux (Wb)
The nominal flux for the machine, in weber. This parameter is required and available only if the Speed controller type parameter is set to
With flux reference output. The default value is0.3.
Inputs and Outputs
NThe speed of the machine, in rpm.
N*The speed reference of the machine, in rpm. When the Regulation type parameter is set to
Torque regulation, this input refers to the torque reference of the machine.MagCA binary signal indicating if the machine is magnetized enough to be started (1) or not (0). This signal is typically provided by another controller that has the capacity to establish the magnetization level of the machine, for example, the Field-Oriented Controller.
This input is available only if the Speed controller type parameter is set to
With flux reference output.Torque*The torque reference, in newton-meter.
CtrlA bus containing these measurements:
Torque reference— In newton-meter.Flux reference (Wb)— This signal is available only when the Speed controller type parameter is set toWith flux reference output.Error— When the Regulation type parameter is set toSpeed regulation, this signal is the speed error (difference between the reference and actual speed). Otherwise, it is zero.Reference— The speed reference, in rpm. When the Regulation type parameter is set toTorque regulation, this measurement refers to the torque reference, in newton-meter.
Flux*The flux reference, in weber. This output is available only when the Speed controller type parameter is set to
With flux reference output.
Examples
The Speed Controller (AC) block is used in the AC3, AC4, AC5, AC6, and AC7 blocks from the Electric Drives library.
References
[1] Bose, B. K. Modern Power Electronics and AC Drives, NJ: Prentice-Hall, 2002.
See Also
Bridge Firing Unit (AC) | Bridge Firing Unit (DC) | Current Controller (Brushless DC) | Current Controller (DC) | Direct Torque Controller | Field-Oriented Controller | Regulation Switch | Six-Step Generator | Space Vector Modulator | Speed Controller (DC) | Speed Controller (Scalar Control) | Vector Controller (PMSM) | Vector Controller (WFSM) | Voltage Controller (DC Bus)