Practical issues in multirate input controllers

Multirate input controllers (MRIC) are a special type of periodic controller which detects all the plant output once and changes the plant input N/sub i//sup th/ times during a frame period T/sub 0/. In this paper, a disadvantage of the MRIC is identified. Specifically, an inappropriate choice of the frame period is shown to result in large entries in the gain matrix of the controller. As a consequence, the actual plant input will acquire extremely large values. To help circumvent the problem, some rules of thumb which will ensure that excessive gain values are avoided when using the MRIC are provided.<>