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Different control tasks within a microgrid are usually classified into a hierarchy including zero, primary, secondary, and tertiary control levels. Generally, power sharing lies in the primary control level and utilizes droop control. Droop control causes deviation of voltage and frequency from their nominal values subsequent to load and generation changes in an islanded microgrid. To eliminate these voltage and frequency deviations, a secondary control level, incorporating low‐bandwidth communication links, is usually employed. However, secondary control increases the complexity and cost of the system. A washout filter–based power sharing approach has been proposed that can maintain the nominal values of the voltage and frequency in the primary control level and thereby eliminate the need for secondary control and communication links. This paper further investigates this concept and derives a state‐space small‐signal model of the proposed washout filter–based power controller in a study microgrid to enable systematic design and performance evaluation, for example, stability and parameter selection. The results are compared with those of the same microgrid with conventional droop power controllers. Finally, simulation case studies are conducted in PSCAD/EMTDC tool to validate the results. [ABSTRACT FROM AUTHOR]

The number of auxiliary electric drives can exceed 100 for luxury cars. Due to their ever‐increasing prevalence, the electromagnetic emissions (EME) of these drives are becoming increasingly important. This work explores the influence of four different stator winding topologies on the electromagnetic emissions and the efficiency performance of fractional horsepower (FHP) brushless direct current (BLDC) drives. Two monofilar windings with a wire diameter of 0.15 and 0.27 mm, an untwisted bifilar winding, and a twisted bifilar winding are inspected. The parasitic stator to winding coupling capacitance is the motor's main source for common mode currents and thus, for radiated emissions. A three‐media capacitance model is introduced to allow estimating this coupling path in the design phase of the motor. Twisting the phases of a bifilar winding reduces the excitation of this path. Therefore, the radiated emissions are reduced by 5 dBμV/m ${\mathrm{B}}_{\mu \text{V/m}}$. The stator winding topology also affects the winding resistance and thus the efficiency. The monofilar winding with a wire diameter of 0.27 mm shows the lowest level of consumed power, followed by the monofilar winding with a wire diameter of 0.15 mm, the untwisted bifilar winding and the twisted bifilar winding. [ABSTRACT FROM AUTHOR]