pathsim.solvers.steadystate module

class pathsim.solvers.steadystate.SteadyState(*solver_args, **solver_kwargs)

Bases: ImplicitSolver

Pseudo-solver that finds the time-independent steady-state solution (DC operating point).

This works by modifying the fixed-point iteration target. Instead of solving \(x_{n+1} = G(x_{n+1})\) for an implicit step, it aims to solve the algebraic equation \(f(x, u, t_{steady}) = 0\) by finding the fixed point of \(x = x + f(x, u, t_{steady})\). It uses the same internal optimizer (e.g., NewtonAnderson) as other implicit solvers.

Characteristics

• Purpose: Find steady-state (\(dx/dt = 0\))

• Implicit (uses optimizer)

• Not a time-stepping method.

solve(f, J, dt)

Solve for steady state by finding x where f(x,u,t) = 0 using the fixed point equation x = x + f(x,u,t).

Parameters:

• f (array_like) – evaluation of function

• J (array_like) – evaluation of jacobian of function

• dt (float) – integration timestep

Returns:

err – residual error of the fixed point update equation

Return type:

float