The invention discloses a high-efficiency wide-limit programmable inverter power supply device and a control method thereof. The device comprises a main loop unit; the input terminal of the main loop unit is connected with commercial power; and the commercial power flows through a filter, a rectifier, and an inverter successively and then the power is transformed into a direct-current signal so as to provide power for a load. The rectifier and the inverter are connected with a programmable control unit. The programmable control unit is configured to preset a voltage effective value, carry out difference processing on the voltage effective value and an effective value fed back by voltage sampling to obtain a voltage error, carry out PI adjustment on the voltage error to generate a voltage amplitude signal with PI adjustment, multiply the voltage amplitude signal with PI adjustment by a sinusoidal wave signal generated by output voltage phase locking of the filter to obtain a sinusoidal modulation voltage signal, subtracting a received voltage instantaneous feedback signal from the sinusoidal modulation voltage signal, carry out PI adjustment, multiplying the adjusted signal with a preset proportionality coefficient to obtain an SPWM voltage pulse width signal. The SPWM voltage pulse width signal is used for driving a switching tube in the rectifier to generate a voltage waveform with a preset amplitude and frequency.