Patent ID: 6920362

Claim:
A control apparatus for controlling a control system having a transfer function regarded as a second order system, comprising: an outer loop configured to execute a negative-feedback of an output scalar x of the controlled system to obtain a deviation scalar e between the output scalar x and a desired value scalar r; a first inner loop configured to execute a negative-feedback of a signal k 1 (dx/dt), obtained by multiplying a gain k 1 to a differentiated value (dx/dt) of the output scalar x of the controlled system, to the deviation scalar e; and a second inner loop configured to use the differentiated value (dx/dt) of the output x of the controlled system and a product, obtained by multiplying a gain k 2 to an absolute value |e| of the deviation scalar e or n powers (n=1,2,3, . . . ) of the absolute value |e|, to execute the positive feedback of a signal of k 2 (dx/dt)·|e| or k 2 (dx/dt)·|e| n to the deviation scalar e, wherein the controlled system is controlled using a signal which is fed back through the first and the second inner loops.