Abstract:
ESDU 69005 presents sets of normalised response curves for simple first- and second-order systems. The data are restricted to certain basic forms of input and to systems that can be described by a linear differential equation with constant coefficients. The characteristic equation, and also the denominator of the corresponding transfer function, is therefore a first- or second-degree polynomial. The response curves for first- and second-order systems are presented and maxima in response to some of the input functions are given. A step input, its time integral (ramp input) and its derivative (impulsive or "Delta function" input) are considered independently although the responses to any two of these inputs can be deduced from the response to the third. Similarly the responses to related inputs of ramp-step and triangular form are given, although these could be deduced by superposition of the responses to suitably chosen ramp inputs. Brief mention is made of the response to an arbitrary input when the response to an impulse is known. Data for the simple frequency response (i.e. the ultimate steady state of a stable system subjected to a sinusoidal input) are presented. In that case the diagrams give the ratio of the amplitudes and the difference in phase of the response and the input. The response to a ramp-step input of a system having a modified form of transfer function is also considered.

See also:

• FIRST-ORDER LINEAR SYSTEM
• LINEAR SYSTEMS
• TRANSFER FUNCTIONS

Details: