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In the report, a new version of machine with DC stator excitation is discussed. A brushless one phase electrical machine has a very simple design. Rotor has no windings. In generator mode operation, stator has one winding for DC stator excitation and one output winding. In motor mode operation, there is only one sensor of rotor position and one phase H-bridge inverter. One phase machine is symmetrical. Like in dc machines, it is possible to realize here: shunt, series, and separate excitation. In motor mode, the speed control is possible by vary armature (output winding) voltage, varying current excitation, and varying resistance in armature circuit. Simplicity construction and flexibility control opportunities can find for this machine wide application in vehicles. Motor, with series excitation, leads a torque-speed characteristic that is useful for transport power circuit applications. One phase machine is the basic for design of two and three phase machines.

In this paper, we consider a new design of synchronous motor with salient poles rotor and all coils placed on the stator. This design, uses a laminated silicon steel rotor, which is not so expensive as a rotor with super strong permanent magnets. This design of machine eliminates copper rings on the rotor and brushes which is used in regular synchronous motors, and eliminates disadvantages involved with these arrangements. In an earlier publication, authors considered the opportunity realization of synchronous mode operation in the machine with salient pole rotor and DC stator excitation. Now, we consider the new synchronous mode operation with individual DC excitation of each the alternative current (AC) windings for realization the first, second and third phase synchronous machines. In theoretical basics of analyses and design of synchronous motors we pay more attention to the single-phase motor because it is the basis for design polyphase synchronous machines.

In transport applications, the synchronous motors are used for the power drives, because of their high operating efficiency, and controllable power factor. Brushless electrical machine with DC stator excitation have on the stator the armature and excitation windings. Rotor is a salient pole construction with laminated core and without coils. On base of this machine can be realized the DC machine. In the synchronous mode operation, there is no need the sensor of rotor position. It is need only alternative current (AC) voltage source. The advantages of the synchronous machine with DC stator excitation are: the simple brushless design, and controllable field excitation. In this paper, we consider the physical principle operation of a new machine with DC stator excitation in the synchronous mode operation. For analysis in a synchronous mode operation, the simplified model of electrical machine in steady state condition is used.

Linear electric motors designed on the basis of permanent magnets have disadvantage. It is caused by nonlinear distribution of a magnetic flux density around the cylindrical permanent magnet. Therefore, the motors should be designed with the high level reserve power. It lids to increase of mass - dimensional parameters of a motor. In addition, it complicates a control system of an electric drive on base of the linear motor. These disadvantages are eliminated by using, offered by authors, of three-zoned permanent magnetic structures. Using the three zone magnetic structures on basis Nd-Fe-B permanent magnets allows reducing weight - dimensional parameters of the linear motor. In this paper is considered design technique of creation the tree zone magnet structure. As an example, it was designed linear electrical motor (actuator) for diesel speed electronic controller. Prototype electronic speed controller was build and tested.

The brushless DC motors with permanent magnets are used primarily in law power applications. There are no limits on weight and motor dimensions in considered motors with DC stator excitation. Brushless series connected machine with DC stator excitation do not have rotor coils. Field coil and armature coils are mounted in the stator. Armature windings are connected to DC voltage source trough power transistors commutator. Power transistors are controlled by reflective optical sensors in function of rotor position. In the report, the new principle design of the motor with DC stator excitation is considered. The new principle of design supposes individual excitation for each of the armature phase. Such approach gives an opportunity to design electrical machine with any number of armature phases spaced in phase from each other. In series connected DC machines, the field winding is connected in series with the armature winding.

DC motors are the most controllable electrical machines but more complicated for fabrication, in comparison with induction motors having simplified design but more complicated for control. Regular DC motor contain excitation (field) coil on the stator and armature coil on the rotor. Armature coil connected with external voltage source by a mechanical commutator with brushes. This arrangement complicates fabrication of DC machine, increases its cost, lowered reliability, and demands regular maintenance. Electromagnets inside of the stator increase dimensions of DC motor. In DC motor with salient pole rotor, there are no coils on the rotor, and mechanical commutator with brushes is eliminated, and eliminated all disadvantages connected with this arrangement. In this paper, we consider the new version of DC machine with DC stator excitation in compare with presented earlier. The difference is in using individual coil excitation for each armature coil, placed on the stator.