The main content of the paper is to propose a new variable switching frequency modulation for suppressing the current ripple of pulse-width-modulation (PWM) inverter. The characteristics of the output current are analyzed, and the analytical expression of the current ripple is derived. Using this modulation method, the inverter can effectively reduce down the current ripple without any sacrifice of efficiency. Compared with the traditional constant switching frequency modulation method with third harmonic injection, the proposed variable switching frequency modulation can further improve the current ripple suppression capability. Finally, experiments verified the theoretical findings.