A power converter apparatus for driving an electronic load is disclosed. The power converter apparatus includes a rectifier module, an active switch unit, a driving module, an input voltage detection module, an output voltage detection module, a current detection module and a digital processor module. The active switch unit is shunt connected to the electronic load. The input voltage detection module is used for sampling out an input sampled voltage waveform. The output voltage detection module is used for sampling out an output sampled voltage waveform. The current detection module is used for sampling out a practical input current waveform. The digital processor module generates a current reference command according to the input sampled voltage waveform and the output sampled voltage waveform. The digital processor module dynamically switches the active switch unit according to the current reference command and the practical input current waveform.