The utility model discloses a three-phase frequency-adjustable phase-shift power supply, which comprises a three-phase wire inlet connector, a bridge arm circuit and an STM32 control panel, the three-phase wire inlet connector is electrically connected with a
rectifier bridge, the
rectifier bridge is electrically connected with a direct-current filter
inductor L1, the direct-current filter
inductor L1 is electrically connected with a
filter capacitor circuit, and the
filter capacitor circuit is electrically connected with the bridge arm circuit. The
rectifier bridge, the direct-current filter
inductor L1 and the
filter capacitor circuit provide
direct current for a loop, the bridge arm circuit is electrically connected with the filter
capacitor circuit, the bridge arm circuit comprises Q1, Q2, Q3, Q4, Q5 and Q6, the bridge arm circuit is electrically connected with an output terminal, the STM32 control panel is electrically connected with a DDS
signal generator, the DDS
signal generator is electrically connected with a three-phase pre-
amplifier, and the three-phase pre-
amplifier is electrically connected with the bridge arm circuit. The three-phase pre-stage
amplifier is electrically connected with the bridge arm circuit, the STM32 control panel generates a command to the DDS
signal generator to generate a digital synthesis waveform, the digital synthesis waveform drives the bridge arm circuit through the three-phase pre-stage amplifier, and a three-phase four-wire
system is formed by output terminals for output.