PWM Generator (Multilevel)
Generate pulses for PWM-controlled modular multilevel converter
Simscape / Electrical / Specialized Power Systems / Power Electronics / Power Electronics Control
The PWM Generator (Multilevel) block generates pulses for a PWM-controlled modular multilevel converter. For a half-bridge converter, carriers are phase-shifted by an angle obtained by dividing 360 degrees by the number of bridges. The number of bridges is a parameter that you specify. For a full-bridge converter, carriers are phase-shifted by an angle obtained by dividing 180 degrees by the number of bridges.
The PWM Generator (Multilevel) block generates
one carrier signal for every power module (full-bridge or half-bridge)
that is controlled. For example, if you set Bridge type to
and Number of bridges to
the block generates 10 carrier signals, each shifted by 18 degrees
(180/10) from the other.
- Bridge Type
Choose whether to control a Half-bridge (default) or a Full-bridge converter.
- Number of bridges
Specify the number of bridges (power modules) of the multilevel converter you want to control. The number of bridges must correspond to the number of power modules used in the modular multilevel converter. The default value is
For example, if you want to control a full-bridge MMC converter that contains 22 power modules (the equivalent of 22 full-bridges), set the Bridge type parameter to
Full-bridgeand the Number of bridges parameter to
22. If you want to control a half-bridge MMC converter that contains 22 power modules (or 22 half-bridges), set Bridge type to
Half-bridgeand Number of bridges to
- Carrier frequency (Hz)
Specify the frequency, in hertz, of the triangular carrier signals. The default value is
- Sample time (s)
Specify the sample time of the block. Set to
0to implement a continuous block. Default is
- Show carriers outport
Select this option to show the
Croutput port for the carriers’ waveforms. By default, this option is cleared.
Inputs and Outputs
Vectorized single-phase sinusoidal reference signal used to generate the output pulses. You specify one reference voltage for each bridge of the multilevel converter you want to control. For linear operation of this block, the magnitude of
Urefmust be between
Vectorized gating signal to control a multilevel converter. When the Bridge type parameter is set to
Half-bridge, the block outputs double the Number of bridges pulses. When the Bridge type parameter is set to
Full-bridge, the block outputs four times the Number of bridges pulses.
Carriers’ waveforms. This outport only appears if you enable the Show carriers outport option.
|Sample Time||Specified in the Sample Time parameter|
Continuous if Sample Time = 0