The invention provides a double parallel active power filtering apparatus which comprises a DSP, a power supply, a
voltage current sampling module, a
serial port communication module, an IGBT gate pole drive circuit, a
high frequency APF circuit and a
low frequency APF circuit. An input terminal of the
voltage current sampling module is connected to an
electrical network, and an output terminal of the
voltage current sampling module is connected to a DSP pin. An output of the DSP is connected to a pin of the IGBT gate pole drive circuit. An output of the IGBT gate pole drive circuit is connected to an IGBT of the
high frequency APF circuit and the
low frequency APF circuit respectively. The
high frequency APF circuit and the
low frequency APF circuit are connected to the
electrical network back. The power supply and the
serial port communication module are externally connected to a DSP port. A voltage
transformer is in parallel connection with a
current transformer to acquire a
signal, a high frequency circuit is parallel connection with a low frequency circuit and the
signal is returned to the
electrical network, the DSP is taken as a
processing unit, a
harmonic wave is effectively filtered, and electrical network current is accurately tracked. A
soft switch drives the IGBT gate pole drive circuit,
zero voltage zero current connection and disconnection of the IGBT are realized,
resonance loss is reduced effectively, and precision is raised.