This paper investigates the operating modes and converter options of dual winding permanent magnet synchronous machines (DWPMSMs) that are used to drive accessories in hybrid electric vehicles. In this application, DWPMSM operate in three different modes: motor-only; generator-only; and simultaneous motor-generator modes. Motor-only and generator-only operations can be treated independently as long as two winding sets are magnetically decoupled. Simultaneous motor-generator mode links two winding sets through a mechanical shaft. As part of this study, the impact of dual winding set usage on the machine's output and performance is also investigated. Experimental results are given for each mode. The converter options of generator winding were investigated as well. These options include uncontrolled rectifier with dc-dc converter and controlled rectifier. Two converters are compared for their impacts on efficiency and generator current harmonics. The relationship between speed and converter control variable is given for various back electromotive force constant values of the DWPMSM.

This study presents a numerical approach to calculate the optimum photovoltaic (PV) tilt angle by considering the three different PV technologies (monocrystalline, polycrystalline, and thin film). This analysis focuses on determination of optimum tilt angle considering seasonal and yearly solar radiation on a plane (Wh/m²) and seasonal and yearly energy production (Wh) of PVs. The angle at maximum global radiation and maximum energy output is considered as the optimum tilt angle. It is found that optimum tilt angles obtained by total radiation and total energy output are different from each other considering seasonal and yearly base. Total radiation-based tilt angle results show that the optimum tilt angle is 13 deg in spring, 9 deg in summer, 17 deg in autumn, 12 deg in winter, and 12 deg as yearly. Energy production-based optimum tilt angles vary from 5 deg to 13 deg for monocrystalline, from 11 deg to 15 deg for polycrystalline, and from 12 deg to 25 deg for thin film technology according to seasonal and yearly tilt angle results.

Maximum power point trackers (MPPTs) play an essential role in extracting power from photovoltaic (PV) panels as they make the solar panels to operate at the maximum power point (MPP) whatever the changes of environmental conditions are. For this reason, they take an important place in the increase of PV system efficiency. MPPTs are driven by MPPT algorithms and a number of MPPT algorithms are proposed in the literature. The comparison of the MPPT algorithms in literature are made by a sun simulator based test system under laboratory conditions for short durations. However, in this study, the performances of four most commonly used MPPT algorithms are compared under real environmental conditions for longer periods. A dual identical experimental setup is designed to make a comparison between two the considered MPPT algorithms as synchronized. As a result of this study, the ranking among these algorithms are presented and the results show that Incremental Conductance (IC) algorithm gives the best performance