A control apparatus for controlling a control target includes: an acquisition unit, a determination unit, and a delay time adding unit. The acquisition unit acquires at least first and second measurement values related to a control target, such as a machine. The determination unit determines whether the control target is in a predetermined state, such as a normal state or an abnormal state, based on the measurement values acquired by the acquisition unit. The delay time adding unit adds delay to at least one of the first and second measurement values.

A method to control a process variable in a process using a control unit includes sequential determination of values of a reference variable to be supplied to the control unit based on values of a first measurand, and sequential determination of values of a regulating variable using values for the reference variable and sequentially determined values for the process variable. A current value for the reference variable is determined by sequentially saving values of the first measurand in a first FIFO memory having a number K of memory locations for saving one value respectively, and by using only the n oldest values saved in the first FIFO memory to determine the current value for the reference variable, with n being a number of values that is smaller than the number K of the values saved in the memory locations of the first FIFO memory and greater or equal 1.

A method to control a process variable in a process by means of a control unit comprises: sequential determination of values of a reference variable to be supplied to the first control unit based on the values of a first measurand; sequential determination of values of a regulating variable using both values for the reference variable and sequentially determined values for the process variable; with a current value for the reference variable being determined: by sequentially saving values of the first measurand, or values derived therefrom, in a first FIFO memory having a number K of memory locations for saving one value respectively, namely a memory featuring a number K of logically consecutive memory locations (j=i) in such a way that the oldest of the values saved in the first FIFO memory is saved in a first memory location (j=1) and the value saved last in the first FIFO memory is saved in a final memory location (j=k); and by using only the n oldest values saved in the first FIFO memory to determine the current value for the reference variable, with n being a number of values that is smaller than the number K of the values saved in the memory locations of the first FIFO memory and greater or equal 1.

A control apparatus for controlling a control target is provided. The control apparatus includes: an acquisition unit configured to acquire a measurement value related to the control target; a determination unit configured to determine whether or not the control target is in a predetermined state based on a plurality of measurement values acquired at predetermined points in time, or based on temporal changes in a plurality of measurement values detected during a predetermined period of time; and a delay time adding unit configured to add a predetermined delay time to at least one measurement value out of the plurality of measurement values that are used by the determination unit to perform determination.

A method to control a process variable in a process using a control unit includes sequential determination of values of a reference variable to be supplied to the control unit based on values of a first measurand, and sequential determination of values of a regulating variable using values for the reference variable and sequentially determined values for the process variable. A current value for the reference variable is determined by sequentially saving values of the first measurand in a first FIFO memory having a number K of memory locations for saving one value respectively, and by using only the n oldest values saved in the first FIFO memory to determine the current value for the reference variable, with n being a number of values that is smaller than the number K of the values saved in the memory locations of the first FIFO memory and greater or equal 1.