Frequency conversion and movable vane combined control system for movable vane adjustable induced draft fan

The invention relates to a frequency conversion and movable vane combined control system for a movable vane adjustable induced draft fan. The system comprises a furnace draft automatic adjustment module and a movable vane opening adjustment module, wherein the furnace draft automatic adjustment module is used for automatically adjusting furnace draft by means of changing the frequency conversion rotating speed of the induced draft fan; the movable vane opening adjustment module is used for making the movable vane opening change along with change of the boiler load by means of establishing a functional relationship between the movable vane opening and the boiler load. Compared with the prior art, the system improves the operating economy and reliability of the induced draft fan, lowers the power consumption rate of a power station and achieves energy conservation and emission reduction.