1. A control apparatus for controlling an object that is modeled using at least one first model parameter and at least one second model parameter, comprising: a partial model parameter identifier for recursively identifying the second parameter based on an output from the object and an input into the object; and a controller for using the first model parameter that is pre-identified and the second model parameter identified by the partial model parameter identifier to determine an input into the object so that the output from the object converges to a desired value.