Abstract Based on the idea of intelligent control and configuration of nine-point controller, the concept of seven-state controller and its three stable control strategies are presented. This controller adopts different control actions according to the phase space composed by error and error change to meet the requirements. The corresponding relations between phase space and response curve of the seven different actions of this controller are analyzed and curve is studies through actions. Under the action of controller, simulation analysis on various second-order targets is carried out. The authors can draw the conclusion that seven-state controller has excellent dynamic performance and robust capability, and can reach satisfactory control result on different control targets.
