**4. Stability of fixed points in delayed PWM switched converters**

In previous section, we show that the procedure based on variational equation can be used to compute Floquet exponents for any number of delays (*τ*). In this section, we compare this approach with other methods which determine stability in switched converters. One of them is the computation of characteristic multipliers based on the jacobian matrix. Another one is the computation of Lyapunov exponents using a numeric routine. Each method gives equivalent information. However Floquet approach is the most appropriated when delays appear since this method does not require the evaluation of the jacobian matrix (its dimension increases when the number of delays is higher). The other two methods have this disadvantage [13].
