Introduces the definition of variable air volume systems, summarizes some virtues of variable air volume systems, introduces the the type of VAV Terminal Unit, and introduces the virtues and disadvantage of VAV Terminal Unit, in the end, this paper discuss the control methods of variable air volume systems,sach as CPT control, VPT control, control method by total air volume and so on.

Test study on a new type of VAV terminal device and VAV system;

The structure and characteristic of VAV automatic control system were analyzed,the method of energy saving used VAV terminal control was discussed,the realization principles of the static pressure control and the fresh air control were introduced,and the operation result was given.