Siemens SINAMICS PERFECT HARMONY GH180 Function Manual page 247

Figure 8-3
Note
Zero sequence voltage
Zero sequence voltage is the DC offset voltage.
The following is a scope picture of the two voltage vectors added together. The higher frequency
voltage waveform VA2 is riding on the lower frequency waveform VA1.
Figure 8-4
The first vector set controls the torque and flux in the motor, and is nearly synchronous. The
second vector set induces losses in the motor to absorb the braking power returned by the first
vector set.
The amplitudes of the two vector sets are coordinated to best utilize the current and voltage
limitations of the converter. If the frequency of the loss-inducing vector set is chosen with the
NXGPro+ Control Manual
Operating Manual, A5E50491925A
Dual Frequency voltages added with normal 3-phase voltages
Dual Frequency Braking waveform
Advanced Operating Functions
8.9 Dual-Frequency Braking
245