This thesis is a development research project for a permanent magnet assisted synchronous reluctance motor (PMaSynRM) used with frequency converter (FC). The motor size is specified to International Electrotechnical Commission (IEC) with frame size 250. The objective of this thesis is to develop air-cooled high dynamic performance (HDP) series motor with PMaSynRM rotor technology. The PMaSynRM designing goals are good thermal behavior and high efficiency at wide speed range with a wide field weakening area.

To study the objectives of this thesis a prototype of PMaSynRM is designed and manufactured. The designed prototype of PMaSynRM is investigated with simulations and measurements at different operating points on a load type of constant torque and constant power with wide field weakening area. The performance values of PMaSynRM prototype rotor is compared with simulations and measurements to an induction motor’s (IM’s) rotor which is earlier manufactured and measured in the same HDP 250 stator.

The simulation and measurement results showed that PMaSynRM has benefits on thermal behavior and efficiency compared to IM. PMaSynRM measured operating points at constant torque from running speed 525 rpm to 1050 rpm and at constant power from 1050 rpm to 3000 rpm showed that PMaSynRM is well suitable to operate in wide speed range because of wide field weakening area.

PMaSynRM simulation and measurement results had a bit difference on the efficiencies because the Adept FCSmek simulation tool does not take into account the high level of supply harmonics outside field weakening area which are produced from frequency converter. The prototype of PMaSynRM reached to higher output level than the IM because of good thermal behavior. The PMaSynRM also met the expectations on high efficiency on a wide field weakening area.