Continuous Systems
Continuous systems are modled through
algebraic and differential system of equations (DAE) with the time as independent
variable.
F(x,dx/dt,t)
where x is the vector of unknowns,
dx/dt vector of derivatives of the unknowns with respect
to time, and t is time.
- no analytical solution
- approximated by using digital techniques
- the unknowns of a DAE are analytic functions
of the time
(they are continuous by intervals with
a finite number of discontinuities)
-
the algorithms of digital resolution solve a DAE system simultaneously
for the values of all the unknowns in all instances determined by the algorithm
-
no object of VHDL obtains these values of a such manner.
For this reason a new class of object is created for the unknown of DAE:
the quantity.
