  A system of three non-identical Josephson junctions connected via an RLC
circuit is considered. The method of Lyapunov exponents charts is used, which
makes it possible to identify the main types of dynamics of the system and to
analyze the dependence of its properties on parameters. The possibility of both
two and three-frequency invariant tori is demonstrated. Saddle-node
bifurcations of resonant tori are studied with the use of instantaneous
Lyapunov exponents. The dependence of the charts on the type of coupling in the
system is discussed.
