Hybrid excitation machines strive to combine the advantages of permanent magnet(PM) machines and wound field synchronous machines, which benefits to reduce the magnet consumption and widen the regulation capability of operating speed or output voltage. Therefore, there are important application value and prospects in the aircraft power and electric vehicles. The existing topologies of hybrid excitation machines are summarized according to the configuration and magnetic circuit. The structural principle and operating characteristics of the rotor-magnetic-shunt hybrid excitation synchronous machine（HESM）and parallel hybrid excitation machine (PHEM) are introduced systematically. The development progress in the rotor- magnetic-shunt HESM is presented, and the basic strategies of generator/motor control are discussed. The new topologies of hybrid excitation machines provide the theory reference and the practice instruction in the development of hybrid excitation machines.