Can PBZ series superimpose a voltage waveform on the output voltage?

Yes, it is possible to superimpose AC voltage and current waveforms on DC voltage and current using an internal signal source. Additionally, PBZ series has an external signal input (EXT SIG IN) terminal, making it possible to combine an internal signal source with an external signal source.
For the details, read the user’s manual – chapter of Basic Features – Selecting a Signal Source.