Critical condition is the most important character of contaminated insulator. In this paper

it is discussed in detail that the calculation of critical condition of contaminated insulator based on optimization algorithm

including modeling

simulation and calculation procedure. A typical model has been calculated by a finite-element software. Since this method can adjust parameters range and sub-step size dynamically

it has high accuracy and convergence speed and can be used in dealing with complex object such as the model with uneven dirty distribution or complex shape. Compared with traditional methods

such as charge simulation

circuit analysis

etc.

the method is more suitable for simulating and analyzing the flashover character of insulators.