The permanent magnet (PM) dual-memory machine incorporates the concept of PM memory machines and PM hybrid machines, hence offering the flexible flux-tuning and flux-mnemonic function. It employs the aluminum-nickel-cobalt (Al-Ni-Co) and neodymium-iron-boron (Nd-Fe-B) PMs as a PM group embedded in each PM pole to complement each other. Thus, it inherently achieves the merit of high working temperature and high power density. Design principles of this new class of machines are devised and discussed. Both simulation and experimentation are given to demonstrate the validity of the proposed design principles.