  We present a general approach to speed up the adiabatic process without
adding the traditional counterdiabatic driving (CD) Hamiltonian. The strategy
is to design an easy-to-get intermediate Hamiltonian to connect the original
Hamiltonian and final transitionless Hamiltonian. With final transitionless
Hamiltonian, the same target can be achieved as in the adiabatic process
governed by the original Hamiltonian, but in a shorter time. We apply the
present approach to a three-level system, and the result shows that the final
transitionless Hamiltonian usually has the same structure as the original
Hamiltonian but with different time-dependent coefficients, allowing speedup to
be achieved in a much easier way compared to previous methods.
