Single-phase active power filter and power supply system

The utility model relates to a single-phase active power filter and a power supply system, the single-phase active power filter comprises a first waveform detection module, a switch on-off device, a filter circuit and a frequency control module, the first waveform detection module is connected into a circuit to be filtered and is used for detecting the waveform of the circuit; the switch on-off device is used for receiving the waveform signal of the first waveform detection module and conducting a corresponding circuit switch arranged in the filter circuit according to the waveform signal of the first waveform detection module; the filter circuit further comprises a low-pass LPF circuit and a high-pass HPF circuit. The low-pass LPF circuit and the high-pass HPF circuit are connected into a circuit to be filtered independently or in a combined mode by conducting corresponding circuit switches through the switch on-off device. And the frequency control module is used for controlling and adjusting cut-off freque