In this paper the problem of resistance measurement of ultrathin conductive lines on dielectric substrates dedicated for printing electronic industry is discussed. The measured line is transformed in a non-invasive way into a resonance circuit. By using a magnetic coupling between the source line and the tested line, the resistance measurement can be performed non-invasively, i:e. without a mechanical contact. The proposed contactless resistance measurement method is based on the resonance quality factor estimation and it is an example of the inverse problem in metrology.

The hybrid excitation synchronous motor (HESM), which aim at combining the advantages of permanent magnet motor and wound excitation motor, have the characteristics of low-speed high-torque hill climbing and wide speed range. Firstly, a new kind of HESM is presented in the paper, and its structure and mathematical model are illustrated. Then, based on a space voltage vector control, a novel flux-weakening method for speed adjustment in the high speed region is presented. The unique feature of the proposed control method is that the HESM driving system keeps the q-axis back-EMF components invariable during the flux-weakening operation process. Moreover, a copper loss minimization algorithm is adopted to reduce the copper loss of the HESM in the high speed region. Lastly, the proposed method is validated by the simulation and the experimental results.