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This generator is a new simplified design version of an alternator with DC stator excitation that was published by the authors in the SAE 2003 and SAE 2004 World Congresses. [7, 8] In automotive applications, this type of electrical machine may be useful for regular cars, hybrid and fuel cell electrical vehicles with an electrical power source system of 12 VDC, 24, and higher. Brushless car alternators with DC stator excitation have less rotor inertia because the excitation windings are located in the stator. Smaller rotor inertia eliminates drive belt slippage. This generator is more reliable in view of the absence of contact rings and graphite brushes in a rotor circuit, which exist in a standard claw-pole alternator [9]. The laminated salient pole rotor of the alternator is very simple in construction and has low cost of production. The two-phase alternator is simpler than the three-phase, as it has only two output windings instead of three.

The electrical power consumption in automobiles continues to increase thereby demanding higher power capability of the alternator. The standard alternator today is a claw-pole synchronous machine. The claw-pole alternators have brushes which are maintenance issue; it is not possible to increase power output by increasing the stack length; and the rotor inertia is large due to the steel core and rotor excitation coil. Despite these disadvantages, the claw-pole alternator is still used because of its low cost and ease of manufacturing. An alternator with DC stator excitation, has a laminated salient pole rotor with no excitation coil. Therefore the weight and inertia is less than in the claw-pole alternator. The excitation coil is located in the stator and therefore there are no brushes needed. In this type of alternator, the stator has three-phase output coils evenly shifted in space 120 degrees.

The three phase electrical motor contains three armature stator coils shifted in space from each other 120 degrees and one stator coil for excitation. Salient multi poles laminated rotor without coil. Rotor has reduced weight because it does not contain coil excitation and has reduced steel core weight. Each of the armature coils is controlled by the one phase H – transistor bridge circuit. DC shoulder of each bridge is connected to a battery. There is an optical sensor of rotor position which controls transistor bridges. Rotor speed may be controlled by change of the armature voltage or by change of current excitation. Current value in both cases is controlled by a pulse-width voltage modulation. In this type of machine, like in DC machines, it is possible to realize shunt, series and combinational methods of the excitation. It is known that series DC motors can develop very high torque at low speeds and therefore can serve very well in a vehicle applications.