Load characteristics-oriented control strategy for air conditioners during voltage sags

As a significant part of electrical load, air conditioners draw attentions for their sometimes-unfriendly load characteristics, especially their dynamic responses during grid voltage disturbances. In this paper, a novel under-voltage control strategy for variable-speed air conditioners is introduced, which can keep air conditioners load characteristic as constant impedances when unexpected voltage disturbances occur. The dynamic responses of three types of air conditioners are analyzed under different voltage sags and interruptions situations. At last, the validity and effectiveness of the proposed strategy are verified by the simulation results.