Analytical and experimental studies of a hybridised synchronous reluctance machine with a variable X d /X q ratio characteristic is the subject of this study. The machine comprises a round rotor and a salient pole machine element that is mechanically coupled together and integrally wound. There are two sets of poly-phase windings in each stator. The windings of one of the sets are transposed between the two sections of the machine. Either set of the windings may be connected to the supply while the other feeds a balanced capacitance load. It is shown that by tuning of the capacitance load that the X d /X q ratio varies theoretically from zero to infinity at very good power factors. The machine characteristics were verified using the generalised two-axis theory and validated by experimentation. The experimental and analytical results obtained show good agreement. Saturation was investigated by using the variation of the d-axis inductance with machine loading. A set of rotor windings may be introduced for the purpose that the machine be self-starting and self-synchronising as a motor. The rotor field windings when fed with dc, will make the machine also capable of operation as a stand-alone salient-pole generator. For this purpose, it was shown that for a very high saliency ratio, reluctance power can be considerably higher than the excitation power.

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A new hybrid synchronous reluctance machine capable of ultra-high Xd/Xq ratio output power has been studied. A d-q model (voltage and flux linkage) of the hybrid synchronous reluctance machine has been idealized and developed. Also the impedance and current loci from steady state analysis of the machine was obtained. The effect of capacitor loading in the auxiliary winding was investigated. The power factor and torque developed in the hybrid synchronous reluctance machine was compared with the conventional synchronous reluctance machine. The hybridized synchronous reluctance machine improved the major constraints of conventional reluctance machinelow power output and poor power factor due to low ratio of direct to quadrature axis reactance (Xd/Xq). To achieve this two elemental synchronous machines was conceived. Both were internally wound with identical winding in the stator. The rotor of one of the synchronous reluctance machine component is round while the other has a salient pole. Both machine halves were mechanically coupled together. One set of the winding of both machines were connected in series and fed from the main while the other set was also connected in series (but transposed between the two section of the of the machine) and then connected to a balanced three phased variable capacitance load. It was the capacitance loading of the auxiliary winding makes the overall Xd/Xqratio of the hybrid machine to be variable that can theoretically attain values between zero and infinity. This translates to ultra-high output and unity power factor.

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