Theory of diseases of steady-state proportional control systems

In many diseases of a semi-stationary nature (chronical diseases) the level of the regulated variable of the diseased system either is too high (a hyper-state disease) or too low (a hypo-state disease). In this paper the steady-state behavior of proportional control systems is, hence, analysed with regard to a longterm pathological change of each single variable or parameter. Each pathological change has its own pattern of changes of the system variables, which also depends upon the system class (left- or right-regulating). Both the block diagram and the regulation characteristic, when used together, allow one to easily derive the pathological behaviour of the system in the steady-state.