The comprehensive power quality control device is a perfect solution to comprehensively solve power quality problems such as grid harmonics, reactive power, and three-phase load imbalance. The power quality comprehensive control device is connected in parallel to the power grid to detect harmonics, reactive power and power in the power grid in real time. The three-phase load unbalanced current is generated by the power electronic converter to generate the reverse compensation current, which dynamically compensates the harmonic current, reactive current and three-phase load unbalanced current in the grid, and can also be based on the reactive power changes on site Switching on and off the capacitor bank and controlling the action of the mechanical stabilizing device for voltage compensation according to voltage fluctuations, and finally fully solving the problems of low voltage, harmonics, reactive power and three-phase load imbalance in the power grid.